2. Surface Water Management Plan Code Revisions
CITY OF
CHANHASSEN
7700 Market Boulevard
PO Box 147
Chanhassen, MN 55317
Administration
Phone: 952.227.1100
Fax: 952.227.1110
Building Inspections
Phone: 952.227.1180
Fax: 952.227.1190
Engineering
Phone 952.227.1160
Fax: 952.227.1170
Finance
Phone: 952.227.1140
Fax: 952.227.1110
Park & Recreation
Phone: 952.227.1120
Fax: 952.227.1110
Recreation Center
2310 Coulter Boulevard
Phone: 952.227.1400
Fax: 952.227.1404
Planning &
Natural Resources
Phone: 952.227.1130
Fax: 952.227.1110
Public Works
1591 Park Road
Phone: 952.227.1300
Fax: 952.227.1310
Senior Center
Phone: 952.227.1125
Fax: 952.227.1110
Web Site
www.ci.chanhassen.mn.us
[l]
MEMORANDUM
TO: Kate Aanenson, Community Development Director
Lori Haak, Water Resources Coordinator ~JV'/
, OY--~.
December 5, 2006 '
FROM:
DATE:
RE:
Code Revisions Resulting from Adoption of Second Generation
Surface Water Management Plan (SWMP)
BACKGROUND
Over the past two years, the City of Chanhassen has been working to update
its 1994 Surface Water Management Plan. The Second Generation Surface
Water Management Plan (SWMP) was recommended for approval by the
Planning Commission on August 15,2006 and was adopted by the City
Council on August 28, 2006. The SWMP is available on the City's website at
www.ci.chanhassen.mn.us.
The SWMP update process involved a comprehensive review of the goals,
policies and standards that were implemented as part of the 1994 Plan. The
Second Generation SWMP recommended a number of changes to the
standards that are currently employed by the City in the areas of erosion and
sediment control, stormwater management and wetland protection. The
recommended revisions to the City Code will help the City to implement its
Second Generation SWMP and achieve the goals set forth therein.
OVERVIEW
The Planning Commission must hold a public hearing on any changes to
Chapter 18 (Subdivisions) and/or Chapter 20 (Zoning), as well as any changes
to definitions found to Chapter 1 that are related to those chapters. In addition
to Chapters 1, 18 and 20, changes are proposed in Chapters 7, 13 and 19. The
changes proposed within Chapters 7, 13 and 19 are included here for your
information.
ANALYSIS
The revisions are generally intended to bring the code into compliance with
the SWMP and are summarized below.
The City of Chanhassen · A growing community with clean lakes, quality schools, a charming downtown, thriving businesses, winding trails, and beautiful parks. A great place to live, work, and play.
SWMP Code Revisions
December 5, 2006
Page 2 of 3
Chapter 1:
. The definitions in Section 1-2 are amended to remove the previously employed
wetland classifications (Pristine, Natural, Ag/Urban and Utilized) and add the
recommended classifications (Preserve, Manage 1, Manage 2, Manage 3). Several
definitions related to the City's wetland and stormwater management programs are
also added (e.g., Administrative Wetland Permit, City Wetland Inventory, NPDES
Permit, Storm Water Pollution Prevention Program, WCA Agent, Wetland
Management Activity).
Chapter 7:
. Several portions of Chapter 7 related to grading permits are amended to enhance
control of erosion and sediment control measures required for grading sites.
Chapter 13:
. Section 13-2 is amended to include pollution of wetlands and storm sewers as
nmsances.
Chapter 18:
. Section 18-62 is amended to remove the requirement for four inches of topsoil
replacement from this section and to update the reference in code from the City's Best
Management Practice Handbook to the City's Surface Water Management Plan.
Chapter 19:
. Sections 19-101 and 19-102 are amended to prohibit illicit discharges into the City's
storm sewer system. This type of revision is required to bring the code into
compliance with MPCA requirements through the City's NPDES Permit.
· In order to maintain the flow of Chapter 19, the portions of the code currently within
Sections 19-140 through 19-148 are being repealed. New Sections 19-140 through
19-146 are adopted in their place. These new sections include the City's development
standards with respect to stormwater. Then, the sections that were Sections 19-140
through 19-148 are readopted verbatim as Sections 19-200 through 19-208.
. New Sections 19-140 through 19-146 will improve the City's compliance with the
requirements of the City's NPDES Permit. It will also provide developers with the
ability to find all the City's stormwater management requirements within City Code,
something that does not currently exist.
Chapter 20:
. Sections 20-401 through 20-418 (Chapter 20, Article VI, Wetland Protection) are
repealed entirely. This allows staff to restructure the wetland protection portion of
the code. New Sections 20-401 through 20-421 are adopted in their place. The
primary revisions within Article VI are:
o Adopting a City Wetland Inventory map that includes the new wetland
classifications: Preserve, Manage 1, Manage 2 and Manage 3;
SWMP Code Revisions
December 5,2006
Page 3 of3
o Outlining the requirements for wetland delineations;
o Explaining the process for classifying wetlands and appealing existing
classifications;
o Setting new wetland buffer requirements (eliminating average widths), but
keeping existing wetland setbacks;
o Outlining additional protections for wetland buffer strips, including requiring
them to be located on the Certificate of Title and Registered Land Survey and
requiring drainage and utility easements over wetlands and buffer strips; and
o Adding a requirement for Administrative Wetland Permits for wetland
management activities (vegetation management). This will be similar to the
Zoning Permit process currently administered by the Planning Division.
. Because the City's Best Management Practices Handbook is no longer being used,
the phrase "Best Management Practices Handbook" is being replaced by the phrase
"Surface Water Management Plan" in Section 20-1060, Section 20-1061, Section 20-
1072, Section 20-1085, Section 20-1551, Section 20-1552, Section 20-1556 and
Section 20-1561.
. Section 20-1408 is amended to prohibit the construction of impervious surface within
the bluff setback unless specifically authorized within that article.
RECOMMENDA TION
Following a public hearing on the proposed revisions to Chapters 1, 18 and 20, staff
recommends that the Planning Commission adopt the following motion:
"The Planning Commission recommends the City Council adopt ordinances amending
Chapters 1, 7, 13, 18, 19 and 20 of the City Code to bring the code into compliance with
the City's Second Generation Surface Water Management Plan."
A TT ACHMENTS
1. Strikethrough/Bold versions of proposed revisions to City Code, Chapters 1, 7,
13, 18, 19 and 20.
2. Ordinance Amending Chapter 1.
3. Ordinance Amending Chapter 7.
4. Ordinance Amending Chapter 13.
5. Ordinance Amending Chapter 18.
6. Ordinance Amending Chapter 19.
7. Ordinance Amending Chapter 20.
G:\ENG\Lori\Surface Water\2006 SWMP Update\Code Updates\120506 PC Staff Report.doc
CHAPTER 1, GENERAL PROVISIONS.
Sec. 1-2. Rules of construction and definitions.
Administrative Wetland Permit means authorization to perform an activity that is
classified as a Wetland Management Activity. Securing an Administrative Wetland
Permit does not exempt the permittee from obtaining any and all other necessary
permits (e.g., United States Army Corps of Engineers, Minnesota Pollution Control
Agency). (20)
Ag/Urean '.'.'ctlands sec Wetlands, aglureaf1.
Boardwalk means a linear structure extending across wetlands or lakes that is not
supported by posts or poles, but floats or rests upon floats without causing
detrimental impacts to the wetland or lake. (20)
City Wetland Inventory means the official City Wetland Inventory Map depicting the
approximate location and extent of wetlands within Chanhassen. A copy of this
map shall be maintained on the City's GIS database, with both hard and electronic
copies being made available for public review upon request. (20)
Erosion control means best management practices employed to prevent erosion
including, but not limited to: soil stabilization practices, limited grading, mulch,
temporary or permanent cover, and construction phasing as defined in the MPCA
General Construction Permit. (7, 19)
GIS means Geographic Information System, such as ArcView. (20)
Hardcover see Impervious surface.
Impervious surface means any material that substantially reduces or prcvents the
infiltration of storm water. It shall include, but not be limited to, gravel driveways,
parking area, buildings and structures. any material that reduces or eliminates water
infiltration when compared to local native soil surface and structure. Impervious
surfaces include, but are not limited to: bituminous and concrete driveways, pavers
of all material, compacted aggregate, non-porous landscape underlayment,
retaining walls, buildings, rooftops, patios, landscape stepping stones or flagstones,
driveways, pool decking and any other structures. Exemptions include decks when
installed without impervious surface below, landscape rock or mulch with pervious
underlayment.
Manage 1 wetlands means high-quality wetlands that should be protected from
development and other pressures of increased use, including indirect effects of
development. Maintaining natural buffers will help to retain the significant
function these wetlands provide. In the event that impacts to these wetlands cannot
Page 1 of 3
be avoided, replacement ratios for mitigation should exceed the state-required
minimums. (20)
Manage 2 wetlands means wetlands that provide medium functional levels and the
wetland extent should be maintained. These wetlands often provide optimal
restoration opportunity. (20)
Manage 3 wetlands means wetlands that have been substantially disturbed and have
the lowest functions and values. (20)
Minnesota Routine Assessment Method (or MnRAM) means Minnesota Routine
Assessment Method for Evaluating Wetland Functions (MnRAM Version 3.0), or
future versions. (20)
MPCA means the Minnesota Pollution Control Agency.
,Vaturall':ctlands see Wctlands, natural.
NPDES permit means the Minnesota Pollution Control Agency's (MPCA's) National
Pollutant Discharge Elimination System (NPDES) Phase II Municipal Separate
Storm Sewer System (MS4) permit.
Preserve wetlands means exceptional and highest-functioning wetlands, or those
sensitive wetlands receiving conveyed stormwater runoff that have yet retained a
medium level of vegetative diversity/integrity. These wetlands are those that should
be preserved in (or improved to) their most pristine or highest functional capacity
with wide, natural buffers, in perpetuity. (20)
Pristinc ',';ctla1'lds see Wctlands, pristinc.
Sediment control means best management practices employed to prevent sediment
from leaving site including, but not limited to: silt fence, sediment traps, earth dikes,
check dams, subsurface drains, pipe slope drains, storm drain inlet protection and
temporary or permanent sediment basins as defined in the MPCA General
Construction Permit. (7, 19)
Storm Water Pollution Prevention Plan (SWPPP) means a plan for stormwater
discharge that includes erosion prevention measures and sediment controls that,
when implemented, will decrease soil erosion on a parcel of land and decrease off-
site nonpoint pollution, as defined in the MPCA General Construction Permit.
Surface Water Management Plan (SWMP) means the most recently adopted version
of the Chanhassen Surface Water Management Plan.
Utilizcd ',',;.ater body see Water body, utilizcd.
Page 2 of3
Water body, utilized. Utilized water bodies created for the specific purpose of surface
..vater runoff retention and/or ',vater quality improvements. These water bodies are not to
be classified as '.vetlands even if they take on 'Netland characteristics. 'Netland alteration
permits shall not be required to undertake work on these water bodies. (20)
WCA agent means the city staff member responsible for the administration of the
Minnesota Wetland Conservation Act. (20)
Wetland Conservation Act (or WCA) means the Wetland Conservation Act of 1991,
as amended (M.S. ~ 103F.612 et seq.), and the accompanying rules of the Minnesota
Board of Water and Soil Resources (Minnesota Rules Chapter 8420, as amended).
(20)
Wetland alteration means draining, grading, excavating, filling, removing healthy
native vegetation, or otherwise altering or destroying a wetland. (20)
Wetland management activity means planting seed or live plant material, burning,
chemically treating, removing topsoil or utilizing other means for the sole purpose
of managing native plant communities and/or eradicating invasive, nonnative
vegetation. (20)
Wetlands, ag/urban. \Vetlands that have been influenced by agricultural or urban
(residential, commercial, or industrial) land usage are called aglurban. Influences
include: ovemutrification, soil erosion and sedimentation, and ,,"ater quality degradation.
,A.S a result of these influences there is a loss of plant species diversity, overcrowding and
domination by invasive species such as reed canary grass, and reduction in wildlife
habitat. (20)
Wetlands, natural. Natural 'Netlands are still in their natural state and typically show
little sign of impact from surrounding land usage. The vegetative community of these
\vetlands is characterized by a diversity of plant species with mixed dominance of
species. Other key factors include: presence of natural indicator species, good wildlife
habitat, and being aesthetically pleasing. (20)
Wetlands, pristine. 'Netlands that exist in a natural state and have special and unusual
qualities worth protecting at a high level arc called pristine. These qualities include:
outstanding vegetation community, native species population, rare or unusual species
present, and habitat for rare wildlife species. (20)
Page 3 of 3
CHAPTER 7, BUILDINGS AND BUILDING REGULATIONS
Sec. 7-19. Plans and specifications.
The building official may require that plans and specifications, required by the Minnesota
State Building Code, include a survey of the lot upon which the proposed building or
construction is to be done, prepared and attested by a registered surveyor. An original
signature is required on the certificate of survey. The survey shall provide the following
information unless otherwise approved by the administrative authority:
(1) Scale of drawing and north arrow;
(2) Legal description of property;
(3) Dimensions and bearing of front, rear, and side property lines;
(4) Front, rear, and side yard setback dimensions of all proposed structures;
(5) Location of all existing structures on the property, boulevards, streets and right-
of-way, including but not limited to sanitary and storm manholes, hydrants, catch
basins, power poles, phone boxes, fences, and any encroachments;
(6) Outside dimensions of proposed structure(s) including decks, porches, retaining
walls (include elevations at bottom of footing and top of wall), stoops, stairs,
cantilevers, fireplaces, bay and bow windows, egress window wells;
(7) Location of a benchmark stake established by the surveyor at the front setback
line within 20 feet of the proposed structure. Maintenance of the benchmark stake
once established by the surveyor shall be the responsibility of the permit applicant;
(8) Location of stakes established by the surveyor on side property lines at:
a. Front setback line.
b. Front building line.
c. Rear building line.
The maintenance of these stakes once established by the surveyor shall be the
responsibility of the permit applicant;
(9) Location of first floor elevation of buildings on adjacent lots. Vacant adjacent
lots shall be labeled as such;
(10) Location of all easements of record including but not limited to tree
preservation, wetland conservation, cross-access, etc.;
(11) Existing and proposed elevations at the following locations;
a. Each lot comer.
b. Top of curb or centerline of roadway at each lot line extension.
c. Center of proposed driveway at curb.
d. Grade at comers of proposed structure.
e. Lowest floor level, top of block, garage slab.
(12) Indication of direction of surface water drainage by arrows and impervious
surface calculations for the lot or parcel;
(13) Tree removal, tree preservation and grading plan if required by the
development contract;
(14) Wetland boundaries with ordinary high water level and one hundred-year flood
elevation if applicable;
(15) Driveway grade (minimum--0.50 percent, maximum--ten percent);
Page 1 of 5
(16) All trees in excess of six inches in diameter (diameter measured at four feet
above grade);
(17) All custom-graded lots and lots deviating from the approved grading plan shall
require an as-built survey submitted to the city prior to issuing a certificate of
occupancy;
(18) Wetland buffer areas and wetland or lake setback dimensions;
(19) Other information as required by the city.
(20) Location and type of erosion and sediment control measures to be installed
by permit holder.
(Ord. No. 23-B, S 6.01,2-23-81; Ord. No. 167, S 5,4-27-92; Ord. No. 317, S 3,4-23-01;
Ord. No. 324, S 2, 7-9-01; Ord. No. 351, S 4,11-24-03)
Sec. 7-22. Grading, erosion and sediment control.
(a) A satisfactory erosion and sediment control plan and grading plan consistent with
the city's Best Management Practices Handbook Surface Water Management Plan
must be approved by the city engineer or designee before a building permit is issued for
construction, if the construction will result in disturbing the soil. The erosion and
sediment control plan shall be illustrated and summarized, by the applicant at the
time of application. Guidance documents shall be listed in the Surface Water
Management Plan and on the city web site.
To guarantee compliance with the plan a $500.00 cash escrow or letter of credit,
satisfactory to the city, shall be furnished to the city before a building permit is issued.
The escrow amount may be greater than $500.00 if, after review of the site, the city
deems it necessary to require a greater amount to guarantee compliance. The maximum
escrow allowable per parcel is $5,000.00 per acre. The city may use the escrow or draw
upon the letter of credit to reimburse the city for any labor or material costs it incurs in
securing compliance with the plan or in implementing the plan. If the city draws on the
escrowed funds, no additional building permits shall be issued until the pre-draw escrow
balance has been restored. The city shall endeavor to give notice to the owner or
developer before proceeding, but such notice shall not be required in an emergency as
determined by the city.
(b) The grading and erosion control plan must be consistent with the approved grading
plan for the plat in which the property is located, if any. Areas where the finished slope
will be steeper than five units horizontal to one vertical shall be specifically noted. Also,
location of erosion control devices shall be clearly labeled. '^1 maintenance plan is
required for all erosion and sediment control measures. Erosion and sediment control
measures must be maintained to meet designed performance.
(c) Every effort shall be made to minimize disturbance of existing ground cover. No
grading or filling shall be permitted within 40 feet of the ordinary high water mark of a
water body unless specifically approved by the city. .\ll disturbed areas shall be replaced
'.vith a minimum of four inches of topsoil or black dirt. To minimize the erosion potential
Page 2 of 5
of exposed areas, restoration of ground cover shall be provided within five days after
completion of the .;rading operation.
(d) Every effort shall be made during the building permit application process to
determine the full extent of erosion control required. However, the city engineer may
require additional controls to correct specific site related problems as normal inspections
are performed.
(e) All erosion control noted on the approved plan shall be installed prior to the
initiation of any site grading. Noncompliance with the grading and erosion control plan
shall constitute grounds for an order from the city engineer to halt all construction. All
failing erosion and sediment control measures shall be remedied vlithin 21 hours of
notification on construction sites. Temporary erosion and sediment control measures shall
be removed within 30 days of stabilization.
(f) All construction activity that results in disturbance of the ground shall comply with
the city's Construction Site Erosions and Sediment Control Best Management Practices
Handbook, as amended Surface Water Management Plan.
(g) If the erosion and sediment control measures have not been installed or
maintained ,properly, the city reserves the right to stop further work. Peak discharge
rates may not increase from the existing two, ten and one hundred year storm events
and the one hundred year, ten day snovlmelt.
(h) Compacted soils shall be broken up to a depth greater than six inches prior to final
site stabilization.
(i h) Seed and mulch shall be applied no later than September 15 of each year. Sod shall
be installed no later than October 15 of each year. Temporary or permanent erosion
control shall be installed on all exposed soils not actively being graded consistent
with conditions of NPDES construction permit or as detailed in the 2005 MN DOT
construction specification handbook, specification 2575.
0) Landlocked stormwater basins shall be designed to hold back to back one hundred
year storms.
(k) Proposed projects shall not result in an increase in the bounce or duration of
inundation do"vnstream.
(1) Runoff rates shall be maintained to the predevelopment rates for the one hundred
year storm.
(Ord. No. 176, S 1, 10-12-92; Ord. No. 351, S 5, 11-24-03)
Sec. 7-34. Exempt earth work.
Page 3 of 5
Earth work that is exempt from obtaining a permit pursuant to section 7-33 shall:
(1) Comply with the city's erosion control standards.
(2) Maintain natural or existing drainage patterns.
(3) Comply with the city's other ordinance requirements including tree preservation
and wetland protection.
(4) Obtain all applicable permits as required and work within the requirements
of the permits.
(Ord. No. 128, S 1,5-14-90)
Sec. 7-35. Applications for earth work permits.
(a) An application for an earth work permit shall be processed in accordance with the
same procedures specified in the City Code relating to interim use permits except that
earth work of more than 50 cubic yards of material but less than 1,000 cubic yards of
material in a 12-month period may be approved administratively.
(b) An application for a permit shall contain:
(1) The name and address of the operator and owner of the land, together with proof
of ownership. If the operator and owner are different, both must sign the application.
(2) The correct legal description of the property where the activity is proposed to
occur.
(3) A certified abstract listing the names of all landowners owning property within
500 feet of the boundary of the property described above.
(4) Specifications of the following, using appropriate maps, photographs and
surveys:
a. Proposed grading plan.
b. Proposed stockpile sites.
c. The physical relationship of the proposed designated site to the community
and existing development.
d. Site topography and natural features including location of watercourses and
water bodies.
e. The description and quantity of material to be excavated.
f. The depth of water tables throughout the area.
g. The location and depth of wells and buried garbage, water, and fill.
(5) The purpose of the operation.
(6) The estimated time required to complete the operation.
(7) Hours and months of operation.
(8) A tree survey indicating the location and type of all trees over six inches in
caliper. In a heavily wooded area only the boundaries of the tree areas must be
indicated on the survey.
(9) An end use landscape plan and interim screening plan for the operation period.
(10) The plan of operation, including processing, nature of the processing and
equipment, location of the plant source of water, disposal of water and reuse of water.
(11) Travel routes to and from the site and the number and type of trucks that will be
used.
Page 4 of 5
(12) Plans for drainage, erOSIOn and sediment control, sedimentation and dust
control.
(13) A restoration plan providing for the orderly and continuing restoration of all
disturbed land to a condition equal to or better than that which existed prior to the
earth work. Such plan shall illustrate, using photographs, maps and surveys where
appropriate, the following:
a. The contour of the land prior to excavation and proposed contours after
completion of excavation and after completion of restoration.
b. Those areas of the site to be used for storage of topsoil and overburden.
c. A schedule setting forth the timetable for excavation of land lying within the
extraction facility.
d. The grade of all slopes after restoration, based upon proposed land uses, and
description of the type and quantity of plantings where revegetation is to be
conducted.
e. The criteria and standards to be used to achieve final restoration as well as
intermittent stabilization.
(14) A statement identifying the applicant's program to insure compliance with the
permit conditions, method of response to complaints and resolving conflicts that may
arise as a result of complaints.
(15) Unless exempt under Minnesota Rules, an environmental assessment
worksheet, if required by the city.
(16) A wetland alteration permit, if required by the City Code, which shall be
processed concurrently with the excavation permit application.
(17) Other information required by the city.
(c) Applicants for earth work permits involving less than 1,000 cubic yards of material
must only furnish the information specified in subsections (b)(I), (2), (4a), (5), (6), (7),
(8), (12), (13), (16) and (17).
(Ord. No. 128, ~ 1,5-14-90)
Page 5 of 5
CHAPTER 13, NUISANCES
Sec. 13-2. Illustrative enumeration.
(a) The following are nuisances affecting health, safety, comfort or repose:
(1) Accumulations of manure, animal feces, refuse, garbage, tin cans, bottles, junk,
debris or other waste which are kept so as to result in offensive odors or unsightly
conditions to the discomfort and annoyance of adjacent property owners or the public;
(2) Garbage cans and privy vaults which are not fly-tight;
(3) Dumping the contents of any cesspool, septic tank, privy vault or garbage can
except at places authorized by law;
(4) All noxious weeds, tall grasses, and other rank growths;
(5) The throwing, dumping or depositing of any dead animals, manure, garbage,
waste, decaying matter, ground, sand, stones, ashes, rubbish, tin cans, paper, or other
material of any kind on private or public property;
(6) Dense smoke, noxious or offensive fumes or odors, gas, soot, or cinders in
unreasonable quantities;
(7) Offensive trade and business as defined by statute or ordinance not licensed as
provided by law;
(8) All public exposure of persons having a contagious disease;
(9) The distribution of samples of medicines or drugs unless such samples are placed
in the hands of an adult person;
(10) All decayed, unwholesome, or contaminated food offered for sale to the public;
(11) Carcasses of animals not buried or destroyed within 24 hours after death;
(12) The keeping of horses, cattle, swine, sheep, goats, rabbits, dogs, or other
animals or fowl so as to result in offense odors or disagreeable noises to the
discomfort of adjacent property owners, and allowing any animal or fowl to run at
large; "at large" means off the premises of the owner and not under restraint, and
"owner" means any person who shall own, harbor, keep or have custody of an animal,
or the parents or guardians of a person under 18 years of age who shall own, harbor,
keep or have custody of an animal.
Cross references: Other animal nuisances, S 5-20.
(13) Placing paper, litter or debris on public or private property, or throwing paper,
litter or debris from motor vehicles;
(14) Causing or permitting any unnecessary noises or annoying vibrations.
(15) The pollution of any public well, stream, river, lake, wetland, storm sewer or
body of water by chemical, organic, industrial, agricultural, commercial,
residential, sewage, yard, construction and animal creamery, or industrial wastes
or discharges in quantities exceeding those typically found in nature.
(16) Breeding sites of the Aedes Triseriatus (tree hole mosquito) including but not
limited to: the basal holes of hardwood trees, unused tires (not mounted on wheels),
pots, pans, cans, pails, bottles and other containers left outdoors in which water or
debris may accumulate;
(17) All other acts, omissions, occupations and uses of property which are a menace
to the health of the inhabitants of the city or a considerable number thereof.
(b) The following are nuisances affecting public morals and decency:
Page 1 of 4
(1) Any vehicle used for the illegal transportation of intoxicating liquor;
(c) The following are nuisances affecting public peace and safety;
(1) Reserved;
(2) All buildings, walls and other structures which have been damaged by fire, decay
or otherwise to an extent exceeding one-half of their original value, or which are in
such a hazardous condition or so situated as to endanger the safety of the public;
(3) All explosives, inflammable liquids and other dangerous substances or materials
stored or accumulated in any manner or in any amount other than that provided by
law or ordinance;
(4) All use, possession or display of fireworks except as provided by law or
ordinance;
(5) All buildings and structures, and all alterations thereof made, erected or altered
in violation of ordinances concerning the manner of construction and the materials
used therein;
(6) Obstructions and excavations affecting the use of public streets, alleys, sidewalks
or public grounds, except under such conditions as are provided by ordinance; and
any other excavation left unprotected, uncovered or allowed to exist in such manner
as to attract children or to constitute a hazard to the public;
(7) The piling, storing or keeping of old machinery, wrecked or junked vehicles, or
other junk or debris upon open spaces; "junked vehicle" means a vehicle that is not
registered and which does not possess a current state automobile license, but the
license is not to be the sole factor determining the status of the vehicle;
(8) Obstructing traffic and the free use of public streets or sidewalks;
(9) All hanging signs, awnings and other similar structures over public streets or
sidewalks, or so situated as to endanger public safety, not constructed and maintained
as provided by law or ordinance, or without proper permit;
(10) Permitting rain, water, ice or snow to fall from any building on any public street
or sidewalk or to flow across any public sidewalk;
(11) All dangerous unguarded machinery, equipment or other property in any public
place, or so situated or operated on private property as to attract minor children;
(12) Placing entrance culverts, or doing any act which may alter or affect the
drainage of public streets or alleys or the surface or grade of public streets, alleys or
sidewalks without proper permit;
(13) Making repairs to motor vehicles, or tires in public streets or alleys, excepting
only emergency repairs which will not unduly impede or interfere with traffic;
(14) Throwing, placing, depositing, or burning leaves, trash, lawn clippings, weeds,
grass, or other material in the streets, alleys or gutters;
(15) Erecting, painting or placing of unauthorized traffic signs or advertising signs
in streets, or alleys or on sidewalks;
(16) All trees, hedges, billboards or other obstructions which prevent a clear view of
traffic approaching an intersection in sufficient time to bring a motor vehicle driven at
a reasonable speed to a stop before the intersection is reached;
(17) Any dog which shall kill, wound or harass any other domestic animal;
(18) Any dog which habitually barks in such manner as to disturb the peace;
(19) Any dog which harasses, chases or molests horses, motor vehicles or persons;
Page 2 of 4
(20) To leave any unused ice box, refrigerator, cooler or other box with a door
thereon which will exclude air when shut;
(21) All other conditions, acts, or things which are liable to cause injury to the
person or property.
(22) Reserved.
(23) Reserved.
(24) Nuisance light on residential properties.
a. Definitions. In this section:
(i) Direct glare means an excessive brightness contrast producing a
sensation of visual discomfort resulting from insufficiently shielded light
source in the field of view.
(ii) Intennittent light means any artificial light which flashes, revolves or
fluctuates in such a manner that the variance is easily distinguished by
personal observation.
(iii) Light source means a device (such as a lamp) which provides visible
energy.
(iv) Light trespass means light emitted that is visible beyond the boundaries
of the property on which the light source is located.
(v) Person means an individual, firm, partnership, trustee, agent,
association, corporation, company, governmental agency, club or organization
of any kind.
b. Direct glare and light trespass declared a nuisance. Glare, light trespass and
intermittent artificial light impacting on residential properties between the hours
of 11:00 p.m. and 7:00 a.m., which cause loss of enjoyment, comfort or repose,
and use of such properties as determined under subsection 13-2(24)c. of this
section is declared a nuisance.
c. Nuisance detennined.
(i) Light trespass shall be considered a nuisance when light produces two-
tenths horizontal foot candles or more at approximately four feet from the
ground or floor surface on other residential property at the property line.
(ii) Direct glare shall be considered a nuisance when an artificial light source
has not been properly located, shielded, directed or controlled, and as a result
there is a direct line of sight between the light source or its reflection and a
point five feet above the ground or higher at the property line of other
residential property if such intensity causes discomfort or annoyance.
(iii) Intermittent light shall be considered a nuisance when it impacts upon a
habitable area of other residential property with such intensity and variance as
to cause discomfort or annoyance.
d. Production of light nuisance prohibited. No artificial light source shall be
installed, allowed to be installed or permitted on any property which light sources
is an intermittent light source, or due to its intensity or physical characteristics,
causes direct glare or trespasses onto a residential property in such a manner as to
cause a nuisance during the hours of 11:00 p.m. through 7:00 a.m.
e. Responsibility. It shall be the responsibility of every installer of artificial
lights and every owner or occupant of property on which artificial lights are
installed to comply with subsection 13-2(24)d. of this section.
Page 3 of 4
f. Exemptions. The provisions of subsections 13-2(24)d. and e. of this section
shall not apply where:
(i) Such lights are caused to be installed by the federal, state or local
government or agency, to light public ways or areas for public benefit; or
(ii) Such lights are required by law for safety reasons and there is no
practical way to control them to eliminate the nuisance.
(Ord. No. 22, SS 2--5,2-5-68; Ord. No. 22A, S 1, 10-8-79; Ord. No. 22B, SS 1,2,4-15-
85; Ord. No. 159, S 1,2, 11-18-91; Ord. No. 298, S 2, 2-14-00; Ord. No. 308, S 1, 7-24-
00; Ord. No. 324, S 7, 7-9-01; Ord. No. 373, SS 1--4,4-12-04)
Page 4 of 4
CHAPTER 18, SUBDIVISIONS
Sec. 18-62. Erosion and sediment control.
(a) The development shall conform to the topography and soils to create the least
potential for soil erosion. Four inches of topsoil shall be replaced on all disturbed areas.
(b) The smallest practical increment of land shall be exposed at anyone time during
development.
(c) Detailed requirements for each plat shall be set forth in the development agreement.
(d) Subdivision development shall conform to the city's Construction Site Erosion and
Sediment Control Best Management Practices Handbook, as amended Surface Water
Management Plan.
(Ord. No. 33-D, S 6.7, 2-25-85; Ord. No. 178, S 1, 10-26-92; Ord. No. 318, S 1,4-23-01)
Page 1 of 1
CHAPTER 19, WATER, SEWERS AND SEWAGE DISPOSAL
ARTICLE V. STORM SEWERS
Sec. 19-101. Unlawful discharge.
It shall be unlawful to discharge to any storm sewer any pollutant waters, in accordance
with subsequent provisions of this article and the city's NPDES permit.
Sec. 19-102. Regulations for use of storm sewer.
(a) No person shall discharge or cause to be discharged any of the following described
waters or wastes to any storm sewer:
(1) Any water or wastes which contain industrial, commercial, residential,
construction, agricultural or animal wastes;
(2) Any gasoline, benzene, naphtha, fuel oil, or other flammable or explosive solid,
liquid or gas;
(3) Any solid waste;
(4) Fertilizers, pesticides or herbicides;
(5) Any solid or viscous substance capable of causing obstruction to the flow in
sewers or other interferences with the proper operation of the community storm
system;
(6) Any cement, cement washout or other wastes having a pH lower than 5.5 or
higher than 9.0 or having any other corrosive property capable of causing damage or
hazard to structure, equipment, personal or water resource of the community;
(7) Any waters or wastes containing a toxic or poisonous substance considered a
hazard to humans or animals or create any hazard in the receiving waters of the
storm sewer system. A toxic pollutant shall include but not be limited to any
pollutant identified pursuant to Section 307(a) of the Federal Water Pollution
Control Act;
(8) Any noxious or malodorous gas or substance capable of creating a public
nuisance; or
(9) Wastes which, due to characteristics or strength, result in the violation of the
city's NPDES permit.
(b) No unauthorized person shall maliciously, willfully or negligently break, damage,
destroy, uncover, deface or tamper with any structure, appurtenance or equipment
which is a part of the city storm sewer system.
(c) The following activities shall be determined exempt from the provisions listed in this
article:
(1) City staff or city contractors during the course of conducting maintenance
activities; and
(2) Metropolitan Mosquito Control District during the course of conducting
mosquito control activities.
Page 1 of 11
Repeal Sections 19-140 through 19-148.
ARTICLE VII. SURFACE WATER MANAGEMENT.
Sec. 19-140. Purpose.
The purpose of this ordinance is to implement standards to achieve the goals and
policies set forth in the city's Surface Water Management Plan in order to preserve,
protect and improve the city's surface water resources.
Sec. 19-141. Development standards.
These development standards shall be reflected in plans prepared by developers and/or
project proposers in the design and layout of site plans, subdivisions and water
management features.
Sec. 19-142. Plans required.
All plans shall be reviewed and stamped "Approved by the City Engineer" and all
applicable permits must be obtained prior to commencing construction. For all newly
constructed storm water facilities (ponds, retention areas, infiltration basins, storm
sewer, etc.) or existing facilities that are modified, as-built plans shall be prepared by the
developer. As-built plans shall be signed and certified by a licensed professional
engineer in the State of Minnesota and record drawings shall be provided to the city.
Standard details for many typical storm structures (e.g., storm sewer, outlet structures,
catch basins, sump manholes, etc.) are available on the city's website.
Sec. 19-143. General elements.
(a) Hydrologic Analysis
1. Storm distributions and storm volumes for hydrologic analysis shall be based
upon Hershfield, D.M., 1961, Rainfall Frequency Atlas of the United States for
Durations of 30 Minutes to 24 Hours and Return Periods from 1 to 100 Years,
Technical Publication No. 40 (TP-40).
2. Design of major facilities (e.g., ponds, detention areas, retention areas) shall be
based on the U.S.D.A. NRCS methods, 100-year return period, 24-hour duration,
type II distribution with average soil moisture conditions (AMC-2). The analysis of
flood levels, storage volumes and discharge rates for detention basins shall utilize the
design storm/freeboard evaluation storm concept.
3. Minor drainage systems (storm sewer) shall be analyzed and designed to protect
for the 10 year frequency rainfall, and shall be evaluated for the 100-year frequency
rainfall. Full pipe flow analysis shall be used unless special conditions can be
demonstrated to consider pressure flow.
Page 2 of 11
4. The Rational Method is the accepted design method for the design of minor
systems (storm sewer). The preferred method of design would be a method utilizing a
hydrograph approach with factors for land use and soil moisture conditions. NRCS
methodology is not acceptable for minor system design unless approved by the City
Engineer.
5. Landlocked storm water basins shall be designed to hold back-to-back 100-year
storms. For landlocked areas, available freeboard and infiltration capacity of in-
place soils should be analyzed (if analyzed for unfrozen soil conditions).
(b) Peak Discharge Rates
1. Peak storm water discharge rates and storage volumes from any drainage area,
watershed, subwatershed, detention basin, wetland or conveyor shall be consistent
with the values shown in this plan for the lOO-year storm event.
2. No increase in peak discharge may result from the proposed project for the 1 or 2-
year storm, the lO-year storm and the 100-year storm event. Variances may be
allowed if computations can be provided which demonstrate no adverse downstream
effects will result from the proposed system. Cumulative storm depths for the
required events are:
a) 2- Year - 2.S-inches
b) 1 0- Year = 4.2 inches
c) lOO-Year = 6.0 inches
(c) General Ij'acility Planning
1. Developments shall maximize preservation and use of natural detention areas and
regional detention areas shall be used to the greatest practical extent. Multiple
purpose detention areas are encouraged to maximize maintenance efficiency within
proposed developments while providing the proper flood control and water quality
features.
2. The construction of detention basins will involve the direct participation of
individual developers. Where regional basins serve multiple properties and may lie
outside of the ownership of the specific development, the City and 'VDs will take an
active role on implementing policy. Because the basis for the hydrology is based on
the developer's grading plan, the developer is required to obtain and submit the
certification of a licensed engineer that the detention areas are constructed to the
specifications of the approved design.
Sec. 19-144. Major facility design elements.
(a) Facility Design Criteria
(1) For design or modification of storm water facilities, the following criteria shall be
followed:
Page 3 of 11
a. All hydrologic data and computations shall be based on NRCS (formerly SCS)
methodology. Computer modeling may be completed using HydroCAD,
TR20/TR55, SWMM or comparable City-approved modeling software.
b. Hydraulic computations shall be completed using the rational method for
storm sewer design, or in commonly used software packages including FHW A
HY -8, Geopack, Eagle Point or SWMM compatible software.
c. Water quality modeling shall be completed using Pondnet, P8 Urban
Catchment Model, SLAMM or comparable software.
d. Outlet structure designs shall provide rate controls that limit post-project rates
to not exceed existing rates for 1 or 2-year, 10-year, 100-year events and 100-
yearllO-day snowmelt.
e. An emergency overflow spillway shall be identified and designed to convey
storm flows from events greater than the 100-year event. Extreme events (on the
order of a 10.0 inch event) shall be analyzed to ensure the emergency overflow
spillway will function as designed. An emergency overflow shall be set an
elevation at least 1.5 feet below the lowest adjacent low building elevation.
f. Maximum 3:1 (H:V) side slopes (see diagram that follows).
g. 10:1 (H:V) safety bench from normal water level (see diagram that follows).
h. For basins intended to have permanent water levels, a minimum of four feet of
standing water (dead storage depth) and a maximum of ten feet shall be
provided.
i. Proper allowance shall be made for future access and maintenance. Easements
shall be greater than or equal to 20 feet wide.
j. Separation between the inlet(s) and outlet shall be maximized to prevent short-
circuiting.
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· Bench areas promote growtll of emergent vegetation.
. !\b:\:lmlze dLs tauct" between the Oll tlet and a11lnlets to preyent snort circulting (If flows.
(2) The facility design shall provide adequate live storage to provide protection from
the design storm, consistent with lowest building elevation standards. Lowest
building elevation is defined as the lowest slab elevation for a home or building,
including basements and crawl spaces. The lowest building elevation for structures
adjacent to wetlands and water bodies shall be an elevation three feet above the 100-
year high water level.
Page 4 of 11
(3) Newly constructed or modified detention basins shall provide storage volume
below the outlet (dead storage) to allow for water quality treatment in accordance
with the following, whichever is most restrictive:
a. Water quality features meeting the MPCA NPDES construction permit for
Permanent Storm Water Management Systems;
b. Water quality treatment consistent with NURP criteria (90% removal of TSS
and 60% removal of TP for a standard NURP particle size distribution); and/or
c. For proposed projects in a watershed that directly discharges to a 'Preserve'
water feature (Table 20 of SWMP), NURP plus enhanced treatment is required
as listed below:
1. Storm water ponds are required to include a sediment forebay at the inlet.
The volume of the sediment forebay should be 5 - 15 % of the permanent pool
surface area. The sediment forebay shall be a minimum of 3 feet plus the
depth for sediment storage.
2. Projects in watersheds that discharge directly to Assumption Creek must
incorporate BMPs as outlined in Appendix A C.1, C.2, C.3 and C.5 of the
MPCA NPDES Construction General Permit, and as listed below:
1. During construction.
a. All exposed soil areas with a slope of 3:1 or steeper, that have a
continuous positive slope to a special water must have temporary
erosion protection or permanent cover within 3 days after the area is
no longer actively being worked. All other slopes that have a
continuous positive slope to a special water must have temporary
erosion protection or permanent cover within 7 days after the area is
no longer actively being worked.
b. Temporary sediment basin requirements described in Part III.B.1-5
must be used for common drainage locations that serve an area with
five (5) or more acres disturbed at one time.
2. Post construction. The water quality volume that must be treated by the
project's permanent storm water management system described in Part
III.C. shall be one (1) inch of runoff from the new impervious surfaces
created by the project.
3. Buffer zone. An undisturbed buffer zone of not less than 100 linear feet
from the special water (not including tributaries) shall be maintained at
all times. Exceptions from this requirement for areas, such as water
crossings or limited water access, are allowed if the Permittee fully
documents in the SWPPP the circumstances and reasons that the buffer
encroachment is necessary. All potential water quality, scenic and other
environmental impacts of these exceptions must be minimized and
documented in the SWPPP for the project.
4. Temperature Controls. The permanent storm water management
system must be designed such that the discharge from the project wiII
minimize any increase in the temperature of trout stream receiving waters
resulting from the 1, and 2-year 24-hour precipitation events. This
includes all tributaries of designated trout streams within the section that
Page 5 of 11
the trout stream is located. Projects that discharge to trout streams must
minimize the impact using one or more of the following measures, in order
of preference:
a. Minimize new impervious surfaces.
b. Minimize the discharge from connected impervious surfaces by
discharging to vegetated areas, or grass swales, and through the use of
other non-structural controls.
c. Infiltration or evapotranspiration of runoff in excess of pre-project
conditions (up to the 2-year 24-hour precipitation event).
d. If ponding is used, the design must include an appropriate
combination of measures such as shading, filtered bottom withdrawal,
vegetated swale discharges or constructed wetland treatment cells that
will limit temperature increases. The pond should be designed to draw
down in 24 hours or less.
e. Other methods that will minimize any increase in the temperature of
the trout stream.
d. For proposed projects in a watershed that directly discharges to an
'Improve l' (Table 20 of SWMP) water feature NURP plus enhanced
treatment is required as listed below:
1. Storm water ponds are required to include a sediment forebay at
the inlet. The volume of the sediment fore bay should be 5 - 15 % of
the permanent pool surface area. The sediment forebay shall be a
minimum of 3 feet plus the depth for sediment storage.
2. Projects in watersheds that discharge directly to Riley or Bluff
Creeks must analyze the downstream system to ensure there is no
increase in runoff rates. One way to determine the downstream
effects is to extend the analysis downstream to a point where the
proposed development represents less than ten percent of the total
watershed draining to that point.
(b) Skimmers and Outlets
1. Skimming devices should be designed to remove oils and floatable materials up to
a one-year frequency event. The skimmer should be set 12 inches below the normal
surface water elevation and should control the discharge velocity to 0.5 fps.
2. Outlets shall be evaluated for the need to dissipate energy so as to reduce velocities
to permissible levels as allowed by the soil and vegetation. At a minimum, flared end
sections should be provided with rip rap consistent with Mn/DOT standards. For
areas with high flows or where excessive erosion occurs or is anticipated, energy
dissipation per Federal Highway Administration standards shall be followed.
3. Riprap shall be provided below the channel grade and above the outfall or channel
bottom to insure that rip rap will not be undermined by scour or rendered ineffective
by displacement. Riprap consisting of natural angular stone suitably graded by
weight shall be designed for anticipated velocities. Riprap shall be placed over a
Page 6 of 11
suitable filter material or filter fabric to insure that soil particles do not move
through the rip rap and reduce its stability.
4. For outlets through berms or roadway embankments and all culverts under public
traveled streets, anti-seepage collars shall be used (see diagram in this section). The
collars shall be installed so as to increase the creep distance or seepage line along
conduit by 15 percent. The locations for the use of collars include:
a. All water and pond structures with a pool depth of two feet and two-day
duration.
b. 250 acre watershed or more.
c. Design head of 10 feet or more.
Sec. 19-145. Erosion and sediment control.
(a) Erosion and Sediment Control Plans
1. An erosion and sediment control plan shall be created for any land disturbing
activity. Erosion and sediment control elements shall be implemented before any
grading can begin. A schedule of significant grading work will be required as part of
the erosion and sediment control plan.
2. The MPCA's most recent version of the NPDES Construction Storm Water
Permit shall be used to develop sediment and erosion control plans. Where the
NPDES permit conflicts with City standards, the more stringent standard will apply.
3. Site access roads (entrances to construction sites) shall be graded or otherwise
protected with silt fences, diversion channels or dikes and pipes to prevent sediment
from exiting the site via the access road. Primary site access roads shall be surfaced
with crushed rock or wood chips. The rock entrance shall extend for a minimum
distance of 75 feet (150 for wood chips) beginning at existing paved surface;
additional length may be required as directed by the City. All construction traffic
shall utilize the entire length of the rock entrance.
4. Soil tracked from the site by motor vehicles shall be cleaned from paved roadway
surfaces at least daily or as needed throughout the duration of construction.
Roadway cleaning shall be the responsibility of the party or parties having a permit
with the City.
5. Streambank stabilization and stream bed control structures shall be designed
based on the unique site conditions present including soil conditions, flow rate, slope,
and flow velocity.
6. Where inadequate natural vegetation exists or where it becomes necessary to
remove existing natural vegetation, both temporary vegetative and permanent
vegetative cover shall be addressed in the plans and specifications and be consistent
with the provisions of the NPDES Construction permit.
Page 7 of 11
(b) Sediment Basins
1. Detention basins may be used as temporary sediment retention during the
construction phase. The design should include providing permanent storage volume
for construction and restoration phase sediment accumulation or the removal of the
sediment to restore the required permanent pool volume in the detention area.
2. Detention areas intended to permanently trap sediments shall provide excess dead
storage beyond the required water quality volume, to allow for sediment
accumulation. Sediment basins shall be capable of removing coarse suspended
sediment from storm water for all runoff events and the greatest practical grain size
(#40 typically). Sediment storage volume should be estimated by the universal soil
loss equation and 0.5 tons per watershed acre per year. Volume below the outlet can
be estimated by using the runoff volume resulting from a 2.5" rainfall.
Sec. 19-146. Wetland elements.
(a) Water level fluctuations (peak elevation and duration) for wetlands shall be limited
to two feet and duration not to exceed 48 hours so as to prevent the destruction of
wildlife habitat and wetland vegetation.
(b) Sedimentation basins or sediment removal devices shall be provided prior to
discharge into wetlands.
(c) Variable bottom contours should be considered to provide deeper holes and flat
shallow benches. This feature will provide habitat for diversity of plants and wetland
inhabitants for wetland mitigation sites and storm water basins.
Secs.19-147-19-199. Reserved.
Page 8 of 11
ARTICLE VIII. SURFACE WATER MANAGEMENT UTILITY.
Sec. 19-200. Surface water management utility established.
Surface water management shall be operated as a public utility pursuant to M.S. S 444.075.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-201. Definitions.
The following words, terms, and phrases, when used in this article, shall have the meaning
ascribed to them in this section, except where the context clearly indicates a different
meanmg:
Surface water management budget is the annual budget approved by the city council for
surface water management including planning, monitoring, capital expenditures, personnel,
and equipment.
Surface water managementfee means the quarterly charge for each parcel of nonexempt
property in the city for the management of surface water.
Utility factor means the ratio of runoff volume, in inches, for a particular land use, to the
runoff volume, in inches for a one-third-acre residential lot, assuming a two-inch rainfall and
soil conservation service (SCS) "type B" soil conditions.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-202. Surface water management fees.
(a) The utility factors for various land uses are as follows:
Land Use Utility
Classification Factor
1 Single-family and rural residential 1.00
2 Agricultural 1.00
3 Undeveloped 1.00
4 Medium density residential 2.24
5 High density residential, industrial, office, institutions, 3.34
(churches, schools, government buildings, hospitals)
6 Business/Commercial 4.28
7 Parks, cemeteries, golf courses, arboretum 0.45
8 Parking lots as a principal use 6.14
(b) The surface water management fee for single-family residential property shall be
calculated as follows:
(1) Percentage of runoff in the city attributable to single-family residential property;
Page 9 of 11
(2) Multiplied by an amount equal to 25 percent of the surface water management
budget;
(3) Divided by the estimated total acreage of single-family residential property in the
city; and
(4) Divided by three.
(c) The surface water management fee for each tax parcel classified 1,2, and 3 is the single-
family residential fee. The fee for classifications 4 through 8 shall be calculated as follows:
Fee for a single-family residential tax parcel multiplied by the utility factor multiplied by the
acreage of the parcel.
(Ord. No. 132, S 1,9-24-90; Ord. No. 147, S 1,5-20-91)
Sec. 19-203. Credits.
The city council may adopt policies for adjustment of the surface water management fees.
Information to justify a fee adjustment must be supplied by the property owner. Adjustment of
fees shall not be retroactive.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-204. Exemptions.
The following land uses are exempt from the surface water management fee:
(1) Public right-of-way.
(2) Lakes.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-205. Payment of fee.
Surface water management fees shall be involved quarterly. The amount due as shown on the
invoice shall be payable on or before the twentieth day of the month in which the invoice is
issued. A penalty of ten percent per quarter shall be added to all accounts that are not paid in
full by the due date. The penalty shall be computed on the unpaid balance not paid by the due
date at the time each quarterly statement is prepared. Any prepayment or overpayment of
charges shall be retained by the city and appliedagainst subsequent fees.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-206. Appeal of fee.
If a property owner or person responsible for paying the surface water management fee
believes that a particular fee is incorrect, such person may file a written appeal with the city
clerk. Appeals will be heard by the city council. No adjustment will be made to the utility
factor for property classifications 1, 2, and 3.
Page 10 of 11
(Ord. No. 132, S 1, 9-24-90)
Sec. 19-207. Certification of delinquent fees.
If a s\)rface water management fee is not paid within three months after a billing is issued, the
city council may certify the amount due, together with penalties, to the county auditor to be
collected with other real estate taxes on the parcel.
(Ord. No. 132, S 1,9-24-90)
Sec. 19-208. Surface water management fund.
A separate fund shall be maintained for surface water management fees and expenditures.
(Ord. No. 132, S 1,9-24-90)
Page 11 of 11
CHAPTER 20, ZONING.
Repeal Sections 20-401 through 20-418.
ARTICLE VI. WETLAND PROTECTION.
Sec. 20-401. Findings intent; rules adopted by reference.
(a). Wetlands help maintain water quality, serve to reduce flooding and erosion, act
as sources of food and habitat for a variety of fish and wildlife, and are an integral
part of the community's natural landscape. Wetlands provide the aesthetic benefits
of open space and can be used to provide a natural separation of land uses. It is the
intent of this ordinance to establish a policy of sound stewardship through
coordination of regulations that conserve, protect, enhance, and result in the no net
loss of these environmentally sensitive resources. In addition, it is the intent of the
city to promote the restoration of degraded wetlands.
(b). The intent of this ordinance is to avoid alteration and destruction of wetlands.
When this is not feasible, mitigation must be provided to recreate the function and
value of the lost or altered wetlands.
(c). This ordinance is adopted in part to implement the Wetland Conservation Act
of 1991, as amended (M.S. ~ 103F.612 et seq.), and the accompanying rules of the
Minnesota Board of Water and Soil Resources (Minnesota Rules Chapter 8420, as
amended).
(d). This ordinance incorporates by reference the act and the rules. Terms used in
this ordinance which are defined in the act or the rules have the meanings given
there.
Sec. 20-402. Purpose.
The purpose of this ordinance is to assure the general health, safety, and welfare of
the residents through preservation and conservation of wetlands and sound
management of development by:
(1). Conducting an inventory and classification of all wetlands within the city and
maintaining a comprehensive set of official city maps depicting the approximate
location and extent of wetlands.
(2). Establishing wetland regulations that are coordinated with water quantity and
water quality goals and policies of the Chanhassen Surface Water Management
Plan.
(3). Requiring sound management practices that will protect, conserve, maintain,
enhance and improve the functions and values of wetlands within the community.
Page 1 of 16
(4). Requiring measures designed to maintain and improve water quality in streams
and lakes.
(5). Protecting and enhancing the scenic value of wetlands.
(6). Restricting, controlling and mitigating the harmful effects of development on
wetlands.
(7). Allowing only development that is planned to be compatible with wetland
protection and enhancement.
(8). Providing standards for the alteration of wetlands when alteration is allowed.
(9). Educating and informing the public about the numerous benefits and features
of wetlands and the impacts of urbanization.
(10). Obtaining protective easements over or acquiring fee title to wetlands as
appropriate.
Sec. 20-403. No net loss.
(a). To achieve no net loss of wetland, except as provided under sections 20-417 and
20-418 of this ordinance or authorized by a wetland alteration permit issued by the
city, a person may not drain, grade, excavate, fill, burn, remove healthy native
vegetation, or otherwise alter or destroy a wetland of any size or type. Any
alteration to a wetland permitted by a wetland alteration permit must be fully
mitigated so that there is no net loss of wetlands.
(b). Wetlands shall be subject to the requirements established herein, as well as
restrictions and requirements established by other applicable city ordinances and
regulations. The wetland protection regulations shall not be construed to allow
anything otherwise prohibited in the zoning district where the wetland area is
located.
(c). All activities within the City shall comply with the Wetland Conservation Act of
1991, as amended (M.S. ~ 103F.612 et seq.), and the accompanying rules of the
Minnesota Board of Water and Soil Resources (Minnesota Rules Chapter 8420, as
amended). Where the requirements of City Code differ from those requirements,
the more restrictive shall apply.
Sec. 20-404. Official wetland map.
(a). The City shall maintain the official City Wetland Inventory, which is hereby
adopted by reference. An electronic copy of this map shall be maintained on the
Page 2 of 16
City's Geographic Information System (GIS) database, with both hard and
electronic copies being made available for public review upon request.
(b). The City Wetland Inventory shall identify each basin as one of four
management categories: Preserve, Manage 1, Manage 2, and Manage 3. These
classifications will be determined using Figure 1.1 "Wetland Management
Classification Process Flowchart for Basic Wetland Protection" from Minnesota
Routine Assessment Method for Evaluating Wetland Functions (MnRAM Version
3.0), or future versions.
(c). The presence or absence of a wetland on the City Wetland Inventory does not
represent a definitive determination as to whether a jurisdictional wetland that
would be covered by this ordinance is present. Wetlands identified during a site-
specific delineation, but not identified by the City Wetland Inventory, are still
subject to the provisions of this ordinance.
(d). The City Wetland Inventory does not depict delineated wetland boundaries and
shall not be used as such.
(e). The City Wetland Inventory shall be amended to include any wetlands
discovered during the site review process.
Sec. 20-405. Wetland delineation.
(a). It is the responsibility of the project applicant to determine whether a wetland
exists on a subject property. It is the responsibility of the applicant to complete a
wetland delineation and submit sufficient documentation of the wetland boundary
to the city in a Wetland Delineation Report. Wetland delineations shall be
completed by, or under the direct supervision of, a Certified Wetland Delineator.
Three (3) hard copies of the Wetland Delineation Report must be submitted to the
city's WCA agent. Additionally, an electronic copy of the delineated wetland
boundaries must be submitted in a format compatible with the city's GIS database.
Wetland delineations shall be valid for three years. Wetland delineations completed
more than three (3) years prior may be confirmed and/or updated by a qualified
wetland professional through a site visit and submittal of a summary of the findings,
a copy of the old delineation and a map depicting both the original and revised
wetland boundaries, where applicable.
(b). Wetland delineations do not need to be completed for properties adjacent to a
proposed development that is under separate ownership. However, sufficient
information must be presented to demonstrate that any proposed activities shall not
directly or indirectly impact adjacent basins. The applicant shall review readily
available information including, but not limited to, the City Wetland Inventory,
National Wetland Inventory maps, topographic maps, soil survey maps, and recent
and historic aerial photographs in preparing this assessment.
Page 3 of 16
Sec. 20-406. Wetland classification.
(a). All wetlands delineated under section 20-405 of this ordinance that have not
been previously classified shall be classified using the results from the Minnesota
Routine Assessment Method for Evaluating Wetland Functions (MnRAM Version
3.0), or future versions.
(b). A MnRAM shall be completed by the property owner or applicant for each
previously unclassified wetland. An electronic version of the MnRAM evaluation
must be submitted to and approved by the city to establish the classification of each
wetland prior to any alteration or impact to the wetland.
(c). MnRAM 3.0 assessments have been completed by the City as a component of
the City Wetland Inventory. Applicants; however, may appeal the determination,
and submit a request to change the classification. To do so, the applicant must
submit an electronic copy of the MnRAM for each affected basin to the WCA agent.
The forms must be filled out by a qualified wetland scientist. The WCA agent will
consult with the technical evaluation panel to determine if a change in the
classification is warranted. In all cases, the burden to demonstrate the need for a
change in classification lies with the applicant.
Sec. 20-407. Permit required.
(a). No person shall drain, excavate in the permanent or semipermanent flooded
areas of open water wetlands, or fill a wetland, wholly or partially, or otherwise
impact wetlands without first having a wetland replacement plan or other
determination approved by the city. Draining, grading, excavating, filling, removing
healthy native vegetation, or otherwise altering or destroying a wetland of any size
or type not subject to an exemption under section 20-417 of this chapter requires a
wetland alteration permit. Activity in a wetland requiring a wetland alteration
permit includes, but is not limited to:
(1). Construction of new streets and utilities.
(2). Creation of ponds or dams and alterations of the natural drainageways of
water courses. This shall only be allowed as part of a mitigation project, or to
restore or improve the function and value of the wetland.
(3). Installation of boardwalks and docks. Docks shall meet the additional
requirements in Chapter 6, Article II of the Chanhassen City Code.
(4). Discharge of untreated stormwater runoff into wetlands.
(5). Changes in wetland hydrology that result in an increase in the ordinary
high water level of a wetland by more than 12 inches.
Page 4 of 16
(b). The city must be notified at least five business days prior to the use of any form
of treatment of wetlands to control nuisance vegetation including chemically
treating, burning, mowing or biologically treating wetlands.
(1). At the time of notification, a person or company will be required to supply
the following information:
a. Location of wetland;
b. Area of wetland to be treated;
c. Name, address and telephone number of the party responsible for
treatment;
d. Name, address and telephone number of person or persons performing
the treatment;
e. Date of treatment;
f. A list of the type of treatments to be used at such time;
g. A statement indicating an understanding of the treatment being applied
and its effect on humans, plants and wildlife; and
h. A signed consent from all property owners owning property containing or
abutting wetland to be treated.
(c). The following activities shall be determined exempt from the provisions listed in
subpart (b) above:
(1) Federal, state or local government staff or contractors during the course of
conducting maintenance activities; and
(2) Metropolitan Mosquito Control District during the course of conducting
mosquito control activities.
Sec. 20-408. Exemptions from earth work permit requirements.
Earth work completed in accordance with an approved wetland alteration permit is
exempt from the requirement to obtain a separate earth work permit.
Sec. 20-409. Permit application requirements and decisions.
(a). A wetland alteration permit shall not be issued without having been first
reviewed by the planning commission and approved by the city council following the
review and hearing procedures set forth for conditional use permits and the
additional requirement of Minnesota Rules 8420.0230. The applicant shall have the
burden of proving that the proposed use or activity complies with the purposes,
intent and other provisions of this ordinance. The council may establish reasonable
conditions which are specifically set forth in the permit to ensure compliance with
requirements contained in this ordinance. Such conditions may, among other
matters, limit the size, kind or character of the proposed work; require the
construction of other structures; require replacement of vegetation and wetland
functions and values; establish required monitoring procedures and maintenance
Page 5 of 16
activities; stage the work over time; require the alteration of the site design to
ensure buffering; and/or require the provision of a performance security.
(b). Any projects seeking a wetland alteration permit subject to this ordinance will
be required to submit the following:
(1). A wetland alteration permit application
(2). A site/grading plan of the entire property
(3). Existing and proposed drainage areas to wetlands
(4). A wetland delineation report in accordance with section 20-405
(5). Wetland classification information in accordance with section 20-406 for
each wetland on property
(6). Buffer strip plan meeting the criteria of section 20-411 (c) and (d)
(7). Submittals required by the Wetland Conservation Act
(8). Topographic data
(9). Other information as required by the city
(c). Decisions made under this ordinance that fall under the authority of the
Minnesota Wetland Conservation Act may be appealed to the Minnesota Board of
Water and Soil Resources under Minnesota Rules 8420.0250, after administration
appeal rights under the official controls have been exhausted. Staff costs to the city
associated with appeals shall be borne by the applicant.
(d). The city council shall appoint a person to serve on a technical evaluation panel.
The person must be a technical professional with expertise in water resources
management. Decisions under this ordinance must not be made until after receiving
the determination of the technical evaluation panel regarding wetland public values,
location, size, and/or type if the city council, the landowner, or a member of the
technical evaluation panel asks for such determinations. This requirement does not
apply to wetlands for which such data is included in an approved comprehensive
wetland management plan per Minnesota Rules 8420.0240. The city council may
seek and consider recommendations, if any, made by the technical evaluation panel
in making replacement plan decisions. Unless otherwise designated, the city's
representative on the technical evaluation panel shall be the WCA agent.
(e). The applicant for a wetland alteration permit is responsible for obtaining all
other necessary permits including but not limited to those required by watershed
districts, Minnesota Department of Natural Resources, United States Army Corps of
Engineers and Minnesota Pollution Control Agency prior to commencement of the
permitted work.
Sec. 20-410. General standards.
(a). The following standards apply to all lands within and abutting a wetland:
(1). Septic and soil absorption system must be a setback minimum of 75 feet
from the ordinary high water mark of the wetland.
Page 6 of 16
(2). The lowest ground floor elevation of a principal structure is three feet above
the 100-year flood elevation of the wetland.
(3). Access across a wetland shall be by means of a boardwalk or elevated
structure and only upon approval of a wetland alteration permit. Wetland
crossings must also be in conformance with all other state regulations.
(4). Docks and boardwalks shall be elevated a minimum of six inches above the
ordinary high water mark. Docks and boardwalks shall only be permitted to
cross wetlands in instances where a wetland is riparian to a lake.
(5). The erosion and sediment control goals and policies within the city's Surface
Water Management Plan shall be met.
(6). Stormwater runoff shall not be discharged into wetlands without water
quality pretreatment as prescribed by Chanhassen City Code.
(b). When a wetland alteration permit is issued allowing wetland alteration, the
following standards shall be followed:
(1). The alteration will not have a net adverse effect on the ecological and
hydrological characteristics of remaining wetland.
(2). It shall be located as to minimize the impact on vegetation.
(3). It shall not adversely change water flow.
(4). The size of the altered area shall be limited to the minimum required for the
proposed action.
(5). The disposal of any excess material is prohibited within remaining wetland
areas.
(6). The disposal of any excess material shall include proper erosion control and
nutrient retention measures.
(7). Alterations to any wetland area are prohibited during waterfowl breeding
season or fish spawning season, unless it is determined by the city that the
wetland is not used for waterfowl breeding or fish spawning.
(8). Alterations to wetland areas shall be mitigated in accordance with the
requirements of this ordinance if the activity results in a loss of wetland area
and/or function and value of the wetland.
(9). Dedicated buffers in accordance with section 20-411.
Sec. 20-411. Placement of structures.
(a). For lots created on or after (date of codification), a buffer strip shall be
maintained abutting all wetlands. All existing vegetation adjacent to a wetland shall
be left undisturbed and applied toward the buffer strip unless otherwise approved
by the WCA agent or city council. Buffer strip vegetation shall be established and
maintained in accordance with the following requirements. If the buffer strip is
disturbed, native plant species shall be selected from wetland and upland plants to
Page 7 of 16
provide diverse habitat for various species of wildlife. Buffer strips shall be
identified by permanent monumentation acceptable to the city. A minimum of one
wetland buffer monument is required per lot abutting the wetland edge. The
maximum spacing between monuments is 300 feet.
(b). The following table provides the minimum standards required for each wetland
classification.
Structure Setback Permanent Buffer Percent of Buffer
Wetland from Buffer Edge Strip Minimum Strip in Native
Classification (feet) Width (feet) Ve2etation
Preserve 50 50 100%
Mana2e 1 40 30 100%
Manage 2 40 25 Over 50 %
Mana2e 3 40 20 Over 50 %
I
I
I
SThI:.I:I
31'
CO' ~/W
I
I
I
I
I
I
I
MANAGE 3 WETLAND IllUSTRATION
BUFFER
HOME I
'SETBACK
FROM WET1.AHD
BUFFER
C 40'
\
\
(c). For lots of record prior to (date of codification), the minimum buffer strip and
setback requirements shall comply with subparagraph (b) above. If buffer strips
and setbacks were approved as part of the subdivision, those standards shall
prevail, except that in no case shall structures be set back less than 40 feet from the
wetland edge.
Page 8 of 16
(d). The Planning Commission or City Council may approve variances from
applicable buffer strips and setback requirements if suitable hardship can be
demonstrated. In these instances, additional performance standards may be
enforced to compensate for the reduced buffer strip widths or setbacks.
(e). In addition to the requirements above, wetland buffer strips for wetland
mitigation areas and those counted as Public Value Credit (PVC) shall also conform
to the minimum standards as set forth by the Wetland Conservation Act.
(0. No structures are to be placed within the wetland setback.
(g). For any subdivision, the locations of buffer strips and wetland setbacks shall be
surveyed and recorded on the Property Title and Certificate of Survey. A
Certificate of Occupancy shall not be issued unless this task is completed and
approved by City staff.
(h). Retaining walls may be located within wetland setbacks, but neither the walls
nor the land alteration that takes place as part of wall construction shall encroach
into the required buffer strips.
Sec. 20-412. Buffer strips required.
(a). Before release of final plat, the applicant must submit to the WCA agent a
drainage and utility easement for protection of the wetland and approved buffer
strip. The easement must describe the boundaries of the wetland and the wetland
buffer strips
(b). Building structures, paving, mowing, introducing non-native vegetation,
cutting, filling, dumping, disposing of yard waste, fertilizing, or tampering with the
monuments within buffer strips is prohibited.
(c). Additional wetland impacts shall not be allowed for the creation of buffer strips.
(d). The use of meandering buffer strips to maintain a natural appearance is
encouraged
(e). Where roadways are constructed next to a wetland, a buffer strip shall be
maintained.
(0. Where acceptable natural vegetation exists in a wetland and adjacent buffer
strip, the retention of such vegetation in an undisturbed state shall be required
unless the applicant receives approval to replace such vegetation. A wetland and/or
buffer strip has acceptable vegetation if it is dominated by native tree, shrub, or
grass species, and has not been used for agricultural production in the last five
years.
Page 9 of 16
(g). The WCA agent may deny the use of existing vegetation for the use of buffer
strips if:
1. It is dominated by any species on the state noxious weed list as defined by
Minnesota Statutes, Section 18.76-18.88. These species include species such
as leafy spurge, spotted knapweed, purple loosestrife, and common and
glossy buckthorn;
2. It is present on unstable slopes, has significant bare soil, displays a history of
erosion problems, is prone to gully formation, or does not function for
sediment and nutrient removal;
3. Any areas were used for agricultural production in the last five years; or
4. The buffer strip is disturbed or altered.
(h). If an area is deemed to be unacceptable in its current state, wetland buffer
landscaping plan must be submitted to the WCA agent. This plan shall include at a
minimum:
1. A plan sheet showing the proposed new buffer strip locations and any buffer
strips acceptable as existing. Existing buffer strips shall be identified and
marked to prevent accidental disturbances.
2. A specification as to what seed mixture will be used, or what trees and/or
shrubs will be planted and their locations.
3. A verification that all seed stock and tree species are native to Minnesota and
are of local ecotypes.
4. A detailed specification that identifies the project schedule, materials,
installation or seeding instructions, and costs.
5. A maintenance schedule that describes the activities that will occur for at
least the first two (2) years. This should include a schedule of mowing and
spot spraying for weeds if an area is seeded. Plans that call for periodic
burning shall have additional details and must have special permission prior
to installation.
6. A detail of all Best Management Practices (BMPs) and erosion control plans.
7. A plan identifying the locations of buffer strip markers.
8. An electronic copy of plans in a format compatible with the City GIS
database.
(i). The city may, at their discretion, require a cash escrow or letter of credit up to
110% of the cost to reestablish the buffer strip should it not be successful, not be
maintained, or otherwise require city intervention to maintain the ordinance
requirements.
Sec. 20-413. Wetland alteration.
(a). An applicant for a wetland alteration permit must demonstrate that the activity
impacting a wetland has complied or, through imposition of conditions of approval,
will comply with all of the requirements of the Wetland Conservation Act.
Page 10 of 16
(b). A wetland alteration permit shall not be issued unless the proposed development
complies with this article.
(c). When a wetland alteration permit is issued allowing wetland alteration, the
alteration must be consistent with the city's Surface Water Management Plan and
the Wetland Conservation Act. The alteration shall not alter the hydrological
patterns in the remainder of the wetland, if a portion of the wetland remains, unless
exempted under section 20-417.
Sec. 20-414. Wetland management activities.
Prior to commencement of a wetland management activity, an administrative
wetland permit must be obtained for the activity in accordance with section 20-415.
Sec. 20-415. Administrative wetland permit.
(a). Applications for administrative wetland permits shall be made on a form
supplied by the city. A fee shall be paid as set forth in Chanhassen City Code. The
WCA agent shall review applications to ensure proposed activities are in compliance
with the Wetland Conservation Act and the requirements of this ordinance and are
consistent with approved and/or accepted wetland management practices.
(b). Activities for which administrative wetland permits are approved shall not
contribute to nuisances as defined in the Chanhassen City Code.
Sec. 20-416. Mitigation.
(a). Mitigation intent. Where a wetland alteration permit is approved and mitigation
is required pursuant to City Code and the Wetland Conservation Act, mitigation
must result in an improvement to the wetland function and value. Mitigation plans
must address water quality, improvement, and maintenance of preexisting
hydrological balance and wildlife habitat. The wetland function and value will
include improvement of water quality, maintaining hydrological balance, and
provision of wildlife habitat. Mitigation will be performed at ratios required by the
Minnesota Wetland Conservation Act to achieve replacement of the wetland
function and value.
(b). Mitigation standards. The functions and values of mitigation wetlands shall be
achieved through wetland restoration, creation and/or enhancement. The
mitigation standards found in Minnesota Rules 8420.0550 shall be followed.
(1). Mitigation shall be subject to wetland setback and buffer strip
requirements as set forth in this ordinance.
Page 11 of 16
(2). Mitigation shall at a minimum replace preexisting wetland function and
values through the ratios set forth in Minnesota Rules 8420.0541.
(3). Mitigation, through the buffer strip, shall provide landscaping for
nesting and food for wildlife habitat. The buffer strip shall provide for
wildlife cover and utilize a diversity of native flora (i.e., trees, shrubs, grasses,
herbaceous plants) to encourage wildlife diversity and provide visual variety.
(4). Wetland mitigation shall be undertaken on-site. If this is not feasible,
then mitigation may occur locally within the subwatershed. If this is not
possible, then mitigation ,au occur outside the subwatershed, elsewhere in the
city. If mitigation cannot be accomplished on site, or if the city deems it
necessary to perform mitigation off-site, then the applicant shall be
responsible for providing off-site mitigation within the major subwatershed,
as designated by the Minnesota Wetland Conservation Act, or purchasing
wetland credits from the state wetland bank.
(d). Construction management and long term wetland maintenance.
(1). The wetland alteration permit holder shall follow best management
practices to minimize direct impacts due to erosion and construction
practices and to safeguard wildlife habitat.
(2). The wetland alteration permit holder shall submit an annual report to
the city for replacement wetlands in Chanhassen. The purpose of the annual
report is to describe actual wetland management, restoration or creation
activities completed during the past year as well as activities planned for the
upcoming year. The annual report shall include all the information required
of annual monitoring reports by Minnesota Rules 8420.0620 subpart 2.
The wetland alteration permit holder shall submit annual monitoring reports
as required by Minnesota Rules 8420.0610. Submission shall continue for at
least five years or until the replacement wetland is deemed by the Technical
Evaluation Panel (TEP) to be fully functional. Where feasible, the city shall
require the wetland alteration permit holder to satisfy long-term
management requirements.
(e). Mitigation Surety. To ensure that the proposed wetland replacement occurs, the
city shall hold either a cash escrow or letter of credit equal to 110% of the current
value of wetland credits on the open market. An additional escrow account shall be
established to ensure that the required monitoring occurs. The monitoring escrow
shall be set at 110% of the current average monitoring expense as performed by an
independent consultant. The monitoring and replacement escrows may be released
incrementally as monitoring and replacement are successfully completed. The
remaining escrow amount will be returned and the letter of credit terminated upon
completion of the monitoring and approval by the Technical Evaluation Panel
Page 12 of 16
(TEP). Any interest earned by holding of a cash escrow shall be the property of the
city.
(f). Within the Minnehaha Creek Watershed District, 1:1 mitigation is required for
excavation within wetlands.
Sec. 20-417. Exemptions and no loss determinations.
(a). Activities exempted by Minnesota Rules 8420.0122 or determined to result in no
net loss of wetlands shall be exempted from the provisions of this ordinance.
However, certificates of exemption or no loss must be obtained from the city prior to
starting work.
(b). A person conducting an activity in a wetland under an exemption shall ensure
that:
(1). Appropriate erosion and sediment control measures are taken to prevent
sediment discharges from the site;
(2). The activity does not block fish activity in a watercourse; and
(3). The activity is conducted in compliance with all other applicable federal,
state, and local requirements, including best management practices as listed
in part 8420.0112, and water resource protection requirements established
under M.S. Ch. 103H.
Sec. 20-418. Variances.
Variances from the requirements of this ordinance may be granted in accordance
with the variance provisions of Article II, Division 3 of this chapter so long as the
variances do not violate the Wetland Conservation Act and rules adopted under the
Act.
Sec. 20-419. Expiration and renewal of permit.
(a). Unless otherwise specified by the city council, the permittee shall begin and
complete the development authorized by the wetland alteration permit within one
year after the date the council approves the permit application.
(b). The permittee shall provide written notice to the city 24 hours prior to the
commencement and completion of the permitted project. No project shall be deemed
to have been completed until approved by the city after receipt of notice of
completion.
(c). If the permittee fails to commence work within the time specified in this section,
the permit shall be void. The permittee may make a written application to the city
council for an extension of the time to commence work, but only if the permittee
submits the application prior to the date already established to commence work.
The application of an extension shall state the reasons the permittee requires an
Page 13 of 16
extension. If the council does not extend the permit, the holder of the void permit
may apply for a new permit.
Sec. 20-420. Inspection of work.
The city may cause inspection of work for which a wetland alteration permit is
issued, at the applicant's expense, to be made periodically during the course of such
work and shall cause final inspection to be made following the completion of the
work.
Sec. 20-421. Enforcement procedures.
(a). Violation of this article, wetland protection, or of the terms of a permit issued
thereunder shall be a misdemeanor.
(b). Any person who alters a wetland in violation of this article shall apply for a
wetland alteration permit and shall pay a filing fee double the regular fee. The city
council may require the violator to restore the wetland or take other mitigative
measures.
Sec. 20-1060. Purpose.
(2) Protect creek corridors, wetlands, and significant stands of mature trees through
the use of careful site design; protective easements; sensitive alignment and design of
roadways and utilities; incorporation of natural features; landscaping and massing of
trees that enhance existing natural features and views; and the practices delineated in
the City's Best Management Practices Handbook Surface Water Management Plan.
Sec. 20-1061. Intent.
(2) Preservation of the natural conditions found on each site to the greatest extent
possible, through minimized removal of trees and other vegetation and soil,
minimized site grading, and application of the practices found in the city's Rest
Management Practices Handbook Surface Water Management Plan.
Sec. 20-1072. Landscaping.
(a) Where natural or existing topographic patterns contribute to the beauty or utility of a
development, they shall be preserved to the greatest extent possible. Modification to
topography will be permitted where and to the extent that it contributes to good design.
All topographic modifications shall adhere to the practices delineated in the city's Rest
Management Practices Handbook Surface Water Management Plan.
Sec. 20-1085. Purpose.
Page 14 of 16
(3) Protect creek corridors, wetlands, and significant stands of mature trees through
the use of careful site design; protective easements; sensitive alignment and design of
roadways/access and utilities; incorporation of natural features; landscaping and
massing of trees that enhance existing natural features and views; and the practices
delineated in the city's Best Management Practices Handbook Surface Water
Management Plan.
Sec. 20-1408. Impervious surfaces.
Creation of impervious surfaces within the bluff setback may contribute to bluff
instability due to increased runoff and/or erosion. Impervious surfaces are
prohibited within the bluff setback unless specifically authorized within this article.
Sec. 20-1551. Purpose.
(a) Protect the Bluff Creek Corridor, wetlands, bluffs, and significant stands of
mature trees through the use of careful site design, protective covenants, sensitive
alignment and design of roadways and utilities, incorporation of natural features,
landscaping, techniques outlined in the city's surface water management plan, and the
practices delineated in the city's Best Management Practices Handbook Surface
Water Management Plan.
Sec. 20-1552. Intent.
(b) Preservation of the natural conditions found in the primary zone and to the
greatest extent possible, preserving significant resources and minimizing impacts in
the secondary zone through cluster development and other practices which minimize
the removal of vegetation, minimize site grading, and application of practices found
in the city's Best Management Practices Handbook Surface Water Management
Plan.
Sec. 20-1556. Impervious cover and slopes.
To the greatest extent possible, all development shall minimize the amount of impervious
surface by clustering development, using common access drives and utility corridors and
minimizing building footprint size. Roads, walkways, bike trails, and parking areas must
be designed parallel to natural contours with consideration to maintaining consolidated
areas of natural topography and vegetation. Management of surface run-off caused by
impervious cover shall be designed using practices delineated in the city's Best
Management Practices Handbook Surface Water Management Plan.
Within the secondary zone of the BCG District, areas with average slopes exceeding 25
percent shall be preserved in their natural state and maintained as permanent open space.
Areas with average slopes less than 25 percent but greater than ten percent shall not
exceed an impervious surface coverage of 25 percent. Impervious coverage for areas
Page 15 of 16
where average slopes are less than ten percent shall be governed by the underlying zoning
district.
Sec. 20-1561. Natural habitat preservation.
(b) Where possible, any disturbances of natural habitat areas within the secondary zone
shall be avoided. Any alterations to the natural habitat within the secondary zone shall
adhere to the practices delineated in the city's Best Management Practices Handbook
Surface Water Management Plan.
Page 16 of 16
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 1
CHANHASSEN CITY CODE, GENERAL PROVISIONS
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. The following terms within Section 1-2 of the City Code, City of
Chanhassen, Minnesota and their definitions, are hereby repealed:
Ag/Urban wetlands.
Natural wetlands.
Pristine wetlands.
Utilized water body.
Water body, utilized.
Wetlands, ag/urban.
Wetlands, natural.
Wetlands, pristine.
Section 2. The definition of "Impervious surface" within Section 1-2 of the City Code,
City of Chanhassen, Minnesota, is hereby amended to read as follows:
Impervious surface means any material that reduces or eliminates water infiltration when
compared to local native soil surface and structure. Impervious surfaces include, but are
not limited to: bituminous and concrete driveways, pavers of all material, compacted
aggregate, non-porous landscape underlayment, retaining walls, buildings, rooftops,
patios, landscape stepping stones or flagstones, driveways, pool decking and any other
structures. Exemptions include decks when installed without impervious surface below,
landscape rock or mulch with pervious underlayment.
Section 3. Section 1-2 of the City Code, City of Chanhassen, Minnesota, is hereby
amended to include the following terms and their definitions:
Administrative Wetland Pennit means authorization to perform an activity that is
classified as a Wetland Management Activity. Securing an Administrative Wetland
Permit does not exempt the permittee from obtaining any and all other necessary permits
(e.g., United States Army Corps of Engineers, Minnesota Pollution Control Agency).
(20)
Boardwalk means a linear structure extending across wetlands or lakes that is not
supported by posts or poles, but floats or rests upon floats without causing detrimental
impacts to the wetland or lake. (20)
City Wetland Inventory means the official City Wetland Inventory Map depicting the
approximate location and extent of wetlands within Chanhassen. A copy of this map
shall be maintained on the City's GIS database, with both hard and electronic copies
being made available for public review upon request. (20)
Erosion control means best management practices employed to prevent erosion
including, but not limited to: soil stabilization practices, limited grading, mulch,
temporary or permanent cover, and construction phasing as defined in the MPCA General
Construction Permit. (7, 19)
GIS means Geographic Information System, such as ArcView. (20)
Hardcover see Impervious surface.
Manage 1 wetlands means high-quality wetlands that should be protected from
development and other pressures of increased use, including indirect effects of
development. Maintaining natural buffers will help to retain the significant function
these wetlands provide. In the event that impacts to these wetlands cannot be avoided,
replacement ratios for mitigation should exceed the state-required minimums. (20)
Manage 2 wetlands means wetlands that provide medium functional levels and the
wetland extent should be maintained. These wetlands often provide optimal restoration
opportunity. (20)
Manage 3 wetlands means wetlands that have been substantially disturbed and have the
lowest functions and values. (20)
Minnesota Routine Assessment Method (or MnRAM) means Minnesota Routine
Assessment Method for Evaluating Wetland Functions (MnRAM Version 3.0), or future
versions. (20)
MPCA means the Minnesota Pollution Control Agency.
NPDES pennit means the Minnesota Pollution Control Agency's (MPCA's) National
Pollutant Discharge Elimination System (NPDES) Phase II Municipal Separate Storm
Sewer System (MS4) permit.
Preserve wetlands means exceptional and highest-functioning wetlands, or those
sensitive wetlands receiving conveyed stormwater runoff that have yet retained a medium
level of vegetative diversity/integrity. These wetlands are those that should be preserved
in (or improved to) their most pristine or highest functional capacity with wide, natural
buffers, in perpetuity. (20)
Sediment control means best management practices employed to prevent sediment from
leaving site including, but not limited to: silt fence, sediment traps, earth dikes, check
dams, subsurface drains, pipe slope drains, storm drain inlet protection and temporary or
permanent sediment basins as defined in the MPCA General Construction Permit. (7, 19)
Storm Water Pollution Prevention Plan (SWPPP) means a plan for stormwater discharge
that includes erosion prevention measures and sediment controls that, when implemented,
will decrease soil erosion on a parcel of land and decrease off-site nonpoint pollution, as
defined in the MPCA General Construction Permit.
Surface Water Management Plan (SWMP) means the most recently adopted version of
the Chanhassen Surface Water Management Plan.
WCA agent means the city staff member responsible for the administration of the
Minnesota Wetland Conservation Act. (20)
Wetland Conservation Act (or WCA) means the Wetland Conservation Act of 1991, as
amended (M.S. 9 103F.612 et seq.), and the accompanying rules of the Minnesota Board
of Water and Soil Resources (Minnesota Rules Chapter 8420, as amended). (20)
Wetland alteration means draining, grading, excavating, filling, removing healthy native
vegetation, or otherwise altering or destroying a wetland. (20)
Wetland management activity means planting seed or live plant material, burning,
chemically treating, removing topsoil or utilizing other means for the sole purpose of
managing native plant communities and/or eradicating invasive, nonnative vegetation.
(20)
Section 4. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _, 200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 7
CHANHASSEN CITY CODE, BUILDINGS AND BUILDING REGULATIONS
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
a section to be numbered Section 7-19 (20) which shall read as follows:
Location and type of erosion and sediment control measures to be installed by permit
holder.
Section. Section 7-22 of the City Code, City of Chanhassen, Minnesota, is hereby
amended to read as follows:
(a) A satisfactory erosion and sediment control plan and grading plan consistent with the
city's Surface Water Management Plan must be approved by the city engineer or designee
before a building permit is issued for construction, if the construction will result in
disturbing the soil. The erosion and sediment control plan shall be illustrated and
summarized, by the applicant at the time of application. Guidance documents shall be
listed in the Surface Water Management Plan and on the city website.
To guarantee compliance with the plan a $500.00 cash escrow or letter of credit,
satisfactory to the city, shall be furnished to the city before a building permit is issued.
The escrow amount may be greater than $500.00 if, after review of the site, the city
deems it necessary to require a greater amount to guarantee compliance. The maximum
escrow allowable per parcel is $5,000.00 per acre. The city may use the escrow or draw
upon the letter of credit to reimburse the city for any labor or material costs it incurs in
securing compliance with the plan or in implementing the plan. If the city draws on the
escrowed funds, no additional building permits shall be issued until the pre-draw escrow
balance has been restored. The city shall endeavor to give notice to the owner or
developer before proceeding, but such notice shall not be required in an emergency as
determined by the city.
(b) The grading and erosion control plan must be consistent with the approved grading
plan for the plat in which the property is located, if any.
(c) Every effort shall be made to minimize disturbance of existing ground cover. No
grading or filling shall be permitted within 40 feet of the ordinary high water mark of a
water body unless specifically approved by the city.
(d) Every effort shall be made during the building permit application process to
determine the full extent of erosion control required. However, the city engineer may
require additional controls to correct specific site related problems as normal inspections
are performed.
(e) All erosion control noted on the approved plan shall be installed prior to the
initiation of any site grading. Noncompliance with the grading and erosion control plan
shall constitute grounds for an order from the city engineer to halt all construction.
(f) All construction activity that results in disturbance of the ground shall comply with
the city's Surface Water Management Plan.
(g) If the erosion and sediment control measures have not been installed or maintained
properly, the city reserves the right to stop further work.
(h) Temporary or permanent erosion control shall be installed on all exposed soils not
actively being graded consistent with conditions of NPDES construction permit or as
detailed in the 2005 MN DOT construction specification handbook, specification 2575.
Section 3. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
a section to be numbered 7-34 (4), which shall read as follows:
Obtain all applicable permits as required and work within the requirements of the
permits.
Section 4. Section 7-35 (b) (12) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Plans for drainage, erosion and sediment control and dust control.
Section 5. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _, 200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 13
CHANHASSEN CITY CODE, NUISANCES
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. Section 13-2 (a) (15) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
The pollution of any public well, stream, river, lake, wetland, storm sewer or body of
water by chemical, organic, industrial, agricultural, commercial, residential, sewage,
yard, construction and animal wastes or discharges in quantities exceeding those typically
found in nature.
Section 2. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _, 200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
(Published in the Chanhassen Villager on
)
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 18
CHANHASSEN CITY CODE, SUBDIVISIONS
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. Section 18-62 (a) of the City Code, City of Chanhassen, Minnesota, is hereby
amended to read as follows:
The development shall conform to the topography and soils to create the least potential
for soil erosion.
Section 2. Section 18-62 (d) of the City Code, City of Chanhassen, Minnesota, is hereby
amended to read as follows:
Subdivision development shall conform to the city's Surface Water Management Plan.
Section 3. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _,200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
(Published in the Chanhassen Villager on
)
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 19
CHANHASSEN CITY CODE, WATER, SEWERS AND SEW AGE DISPOSAL
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
sections to be numbered 19-101 through 19-102, which shall read as follows:
Sec. 19-101. Unlawful discharge.
It shall be unlawful to discharge to any storm sewer any pollutant waters, in accordance
with subsequent provisions of this article and the city's NPDES permit.
Sec. 19-102. Regulations for use of storm sewer.
(a) No person shall discharge or cause to be discharged any of the following described
waters or wastes to any storm sewer:
(1) Any water or wastes which contain industrial, commercial, residential,
construction, agricultural or animal wastes;
(2) Any gasoline, benzene, naphtha, fuel oil, or other flammable or explosive solid,
liquid or gas;
(3) Any solid waste;
(4) Fertilizers, pesticides or herbicides;
(5) Any solid or viscous substance capable of causing obstruction to the flow in
sewers or other interferences with the proper operation of the community storm
system;
(6) Any cement, cement washout or other wastes having a pH lower than 5.5 or
higher than 9.0 or having any other corrosive property capable of causing damage or
hazard to structure, equipment, personal or water resource of the community;
(7) Any waters or wastes containing a toxic or poisonous substance considered a
hazard to humans or animals or create any hazard in the receiving waters of the storm
sewer system. A toxic pollutant shall include but not be limited to any pollutant
identified pursuant to Section 307(a) of the Federal Water Pollution Control Act;
(8) Any noxious or malodorous gas or substance capable of creating a public
nUIsance; or
(9) Wastes which, due to characteristics or strength, result in the violation of the
city's NPDES permit.
(b) No unauthorized person shall maliciously, willfully or negligently break, damage,
destroy, uncover, deface or tamper with any structure, appurtenance or equipment which
is a part of the city storm sewer system.
(c) The following activities shall be determined exempt from the provisions listed in this
article:
(1) City staff or city contractors during the course of conducting maintenance
activities; and
(2) Metropolitan Mosquito Control District during the course of conducting mosquito
control activities.
Section 2. Sections 19-140 through 19-148 of the City Code, City of Chanhassen,
Minnesota, are hereby repealed.
Section 3. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
sections to be numbered 19-140 through 19-146, which shall read as follows:
ARTICLE VII. SURFACE WATER MANAGEMENT.
Sec. 19-140. Purpose.
The purpose of this ordinance is to implement standards to achieve the goals and policies
set fOlth in the city's Surface Water Management Plan in order to preserve, protect and
improve the city's sUlface water resources.
Sec. 19-141. Development standards.
These development standards shall be reflected in plans prepared by developers and/or
project proposers in the design and layout of site plans, subdivisions and water
management features.
Sec. 19-142. Plans required.
All plans shall be reviewed and stamped "Approved by the City Engineer" and all
applicable permits must be obtained prior to commencing construction. For all newly
constructed storm water facilities (ponds, retention areas, infiltration basins, storm sewer,
etc.) or existing facilities that are modified, as-built plans shall be prepared by the
developer. As-built plans shall be signed and certified by a licensed professional engineer
in the State of Minnesota and record drawings shall be provided to the city. Standard
details for many typical storm structures (e.g., storm sewer, outlet structures, catch
basins, sump manholes, etc.) are available on the city's website.
Sec. 19-143. General elements.
(a) Hydrologic Analysis
1. Storm distributions and storm volumes for hydrologic analysis shall be based upon
Hershfield, D.M., 1961, Rainfall Frequency Atlas of the United States for Durations
of 30 Minutes to 24 Hours and Return Peliods from 1 to 100 Years, Technical
Publication No. 40 (TP-40).
2. Design of major facilities (e.g., ponds, detention areas, retention areas) shall be
based on the U.S.D.A. NRCS methods, 100-year return period, 24-hour duration, type
II distribution with average soil moisture conditions (AMC-2). The analysis of flood
levels, storage volumes and discharge rates for detention basins shall utilize the
design storm/freeboard evaluation storm concept.
3. Minor drainage systems (storm sewer) shall be analyzed and designed to protect for
the 10 year frequency rainfall, and shall be evaluated for the 100-year frequency
rainfall. Full pipe flow analysis shall be used unless special conditions can be
demonstrated to consider pressure flow.
4. The Rational Method is the accepted design method for the design of minor
systems (storm sewer). The preferred method of design would be a method utilizing a
hydrograph approach with factors for land use and soil moisture conditions. NRCS
methodology is not acceptable for minor system design unless approved by the City
Engineer.
5. Landlocked storm water basins shall be designed to hold back-to-back 100-year
storms. For landlocked areas, available freeboard and infiltration capacity of in-place
soils should be analyzed (if analyzed for unfrozen soil conditions).
(b) Peak Discharge Rates
1. Peak storm water discharge rates and storage volumes from any drainage area,
watershed, subwatershed, detention basin, wetland or conveyor shall be consistent
with the values shown in this plan for the 100-year storm event.
2. No increase in peak discharge may result from the proposed project for the 1 or 2-
year storm, the to-year storm and the 100-year storm event. Variances may be
allowed if computations can be provided which demonstrate no adverse downstream
effects will result from the proposed system. Cumulative storm depths for the
required events are:
a) 2- Year - 2.8-inches
b) 10- Year = 4.2 inches
c) 100-Year = 6.0 inches
(c) General Facility Planning
1. Developments shall maximize preservation and use of natural detention areas and
regional detention areas shall be used to the greatest practical extent. Multiple
purpose detention areas are encouraged to maximize maintenance efficiency within
proposed developments while providing the proper flood control and water quality
features.
2. The construction of detention basins will involve the direct participation of
individual developers. Where regional basins serve multiple properties and may lie
outside of the ownership of the specific development, the City and WDs will take an
active role on implementing policy. Because the basis for the hydrology is based on
the developer's grading plan, the developer is required to obtain and submit the
certification of a licensed engineer that the detention areas are constructed to the
specifications of the approved design.
Sec. 19-144. Major facility design elements.
(a) Facility Design Criteria
(1) For design or modification of storm water facilities, the following critetia shall be
followed:
a. All hydrologic data and computations shall be based on NRCS (formerly SCS)
methodology. Computer modeling may be completed using HydroCAD,
TR20/TR55, SWMM or comparable City-approved modeling software.
b. Hydraulic computations shall be completed using the rational method for storm
sewer design, or in commonly used software packages including FHW A HY-8,
Geopack, Eagle Point or SWMM compatible software.
c. Water quality modeling shall be completed using Pondnet, P8 Urban
Catchment Model, SLAMM or comparable software.
d. Outlet structure designs shall provide rate controls that limit post-project rates
to not exceed existing rates for 1 or 2-year, lO-year, 100-year events and 100-
year/lO-day snowmelt.
e. An emergency overflow spillway shall be identified and designed to convey
storm flows from events greater than the 100-year event. Extreme events (on the
order of a 10.0 inch event) shall be analyzed to ensure the emergency overflow
spillway will function as designed. An emergency overflow shall be set an
elevation at least 1.5 feet below the lowest adjacent low building elevation.
f. Maximum 3:1 (H:V) side slopes (see diagram that follows).
g. 10: 1 (H: V) safety bench from normal water level (see diagram that follows).
h. For basins intended to have permanent water levels, a minimum of four feet of
standing water (dead storage depth) and a maximum of ten feet shall be provided.
i. Proper allowance shall be made for future access and maintenance. Easements
shall be greater than or equal to 20 feet wide.
j. Separation between the inlet(s) and outlet shall be maximized to prevent shott-
circuiting.
BNrn
Ii'" Stf..r:;lS"
Th'Jfl SrorJ2,"
Em HgNK')' O\'{'fllow ~
Norm :ll'....at.i'.'r Le-.d
100 Yror HiF:b Watcr LFn'l
S..xll1l1\'nt Storns., Yolum'7
Ibml Bottolll
. Bench areas promotr gTUWtll of emergent Yesetat~Jn.
· !"Ia.xlm.l1e dls t3nce b(.tVieen t he outlet mld;:ill Inlets to pren'nt short circuIting of flo',vs.
(2) The facility design shall provide adequate live storage to provide protection from
the design storm, consistent with lowest building elevation standards. Lowest
building elevation is defined as the lowest slab elevation for a home or building,
including basements and crawl spaces. The lowest building elevation for structures
adjacent to wetlands and water bodies shall be an elevation three feet above the 100-
year high water level.
(3) Newly constructed or modified detention basins shall provide storage volume
below the outlet (dead storage) to allow for water quality treatment in accordance
with the following, whichever is most restlictive:
a. Water quality features meeting the MPCA NPDES construction permit for
Permanent Storm Water Management Systems;
b. Water quality treatment consistent with NURP criteria (90% removal of TSS
and 60% removal of TP for a standard NURP pat1icle size distribution); and/or
c. For proposed projects in a watershed that directly discharges to a 'Preserve'
water feature (Table 20 of SWMP), NURP plus enhanced treatment is required as
listed below:
1. Storm water ponds are required to include a sediment forebay at the inlet.
The volume of the sediment forebay should be 5 - 15% of the permanent pool
surface area. The sediment forebay shall be a minimum of 3 feet plus the
depth for sediment storage.
2. Projects in watersheds that discharge directly to Assumption Creek must
incorporate BMPs as outlined in Appendix A C.l, C.2, C.3 and C.5 of the
MPCA NPDES Construction General Permit, and as listed below:
1. During construction.
a. All exposed soil areas with a slope of 3: 1 or steeper, that have a
continuous positive slope to a special water must have temporary
erosion protection or permanent cover within 3 days after the area is
no longer actively being worked. All other slopes that have a
continuous positive slope to a special water must have temporary
erosion protection or permanent cover within 7 days after the area is
no longer actively being worked.
b. Temporary sediment basin requirements described in Part III.B.1-5
must be used for common drainage locations that serve an area with
five (5) or more acres disturbed at one time.
2. Post construction. The water quality volume that must be treated by the
project's permanent storm water management system described in Part
III.C. shall be one (1) inch of runoff from the new impervious surfaces
created by the project.
3. Buffer zone. An undisturbed buffer zone of not less than 100 linear feet
from the special water (not including tributaries) shall be maintained at all
times. Exceptions from this requirement for areas, such as water crossings
or limited water access, are allowed if the Permittee fully documents in the
SWPPP the circumstances and reasons that the buffer encroachment is
necessary. All potential water quality, scenic and other environmental
impacts of these exceptions must be minimized and documented in the
SWPPP for the project.
4. Temperature Controls. The pelmanent storm water management system
must be designed such that the discharge from the project will minimize
any increase in the temperature of trout stream receiving waters resulting
from the 1, and 2-year 24-hour precipitation events. This includes all
tributaries of designated trout streams within the section that the trout
stream is located. Projects that discharge to trout streams must minimize
the impact using one or more of the following measures, in order of
preference:
a. Minimize new impervious surfaces.
b. Minimize the discharge from connected impervious surfaces by
discharging to vegetated areas, or grass swales, and through the use of
other non-structural controls.
c. Infiltration or evapotranspiration of runoff in excess of pre-project
conditions (up to the 2-year 24-hour precipitation event).
d. If ponding is used, the design must include an appropriate
combination of measures such as shading, filtered bottom withdrawal,
vegetated swale discharges or constructed wetland treatment cells that
will limit temperature increases. The pond should be designed to draw
down in 24 hours or less.
e. Other methods that will minimize any increase in the temperature of
the trout stream.
d. For proposed projects in a watershed that directly discharges to an
'Improve l' (Table 20 of SWMP) water feature NURP plus enhanced
treatment is required as listed below:
1. Storm water ponds are required to include a sediment forebay at
the inlet. The volume of the sediment forebay should be 5 - 15%
of the permanent pool smface area. The sediment forebay shall be
a minimum of 3 feet plus the depth for sediment storage.
2. Projects in watersheds that discharge directly to Riley or Bluff
Creeks must analyze the downstream system to ensure there is no
increase in runoff rates. One way to determine the downstream
effects is to extend the analysis downstream to a point where the
proposed development represents less than ten percent of the total
watershed draining to that point.
(b) Skimmers and Outlets
1. Skimming devices should be designed to remove oils and floatable materials up to
a one-year frequency event. The skimmer should be set 12 inches below the normal
surface water elevation and should control the discharge velocity to 0.5 fps.
2. Outlets shall be evaluated for the need to dissipate energy so as to reduce velocities
to pelmissible levels as allowed by the soil and vegetation. At a minimum, flared end
sections should be provided with riprap consistent with Mn/DOT standards. For areas
with high flows or where excessive erosion occurs or is anticipated, energy
dissipation per Federal Highway Administration standards shall be followed.
3. Riprap shall be provided below the channel grade and above the outfall or channel
bottom to insure that riprap will not be undermined by scour or rendered ineffective
by displacement. Riprap consisting of natural angular stone suitably graded by weight
shall be designed for anticipated velocities. Riprap shall be placed over a suitable
filter material or filter fabric to insure that soil particles do not move through the
riprap and reduce its stability.
4. For outlets through berms or roadway embankments and all culverts under public
traveled streets, anti-seepage collars shall be used (see diagram in this section). The
collars shall be installed so as to increase the creep distance or seepage line along
conduit by 15 percent. The locations for the use of collars include:
a. All water and pond structures with a pool depth of two feet and two-day
duration.
b. 250 acre watershed or more.
c. Design head of 10 feet or more.
Sec. 19-145. Erosion and sediment control.
(a) Erosion and Sediment Control Plans
1. An erosion and sediment control plan shall be created for any land disturbing
activity. Erosion and sediment control elements shall be implemented before any
grading can begin. A schedule of significant grading work will be required as part of
the erosion and sediment control plan.
2. The MPCA's most recent version of the NPDES Construction StOlm Water Pelmit
shall be used to develop sediment and erosion control plans. Where the NPDES
permit conflicts with City standards, the more stringent standard will apply.
3. Site access roads (entrances to construction sites) shall be graded or otherwise
protected with silt fences, diversion channels or dikes and pipes to prevent sediment
from exiting the site via the access road. Primary site access roads shall be surfaced
with crushed rock or wood chips. The rock entrance shall extend for a minimum
distance of 75 feet (150 for wood chips) beginning at existing paved surface;
additional length may be required as directed by the City. All construction traffic
shall utilize the entire length of the rock entrance.
4. Soil tracked from the site by motor vehicles shall be cleaned from paved roadway
surfaces at least daily or as needed throughout the duration of construction. Roadway
cleaning shall be the responsibility of the party or parties having a pelmit with the
City.
5. Streambank stabilization and stream bed control structures shall be designed based
on the unique site conditions present including soil conditions, flow rate, slope, and
flow velocity.
6. Where inadequate natural vegetation exists or where it becomes necessary to
remove existing natural vegetation, both temporary vegetative and permanent
vegetative cover shall be addressed in the plans and specifications and be consistent
with the provisions of the NPDES Construction permit.
(b) Sediment Basins
1. Detention basins may be used as temporary sediment retention during the
construction phase. The design should include providing permanent storage volume
for construction and restoration phase sediment accumulation or the removal of the
sediment to restore the required permanent pool volume in the detention area.
2. Detention areas intended to permanently trap sediments shall provide excess dead
storage beyond the required water quality volume, to allow for sediment
accumulation. Sediment basins shall be capable of removing coarse suspended
sediment from storm water for all runoff events and the greatest practical grain size
(#40 typically). Sediment storage volume should be estimated by the universal soil
loss equation and 0.5 tons per watershed acre per year. Volume below the outlet can
be estimated by using the runoff volume resulting from a 2.5" rainfall.
Sec. 19-146. Wetland elements.
(a) Water level fluctuations (peak elevation and duration) for wetlands shall be limited to
two feet and duration not to exceed 48 hours so as to prevent the destruction of wildlife
habitat and wetland vegetation.
(b) Sedimentation basins or sediment removal devices shall be provided prior to
discharge into wetlands.
(c) Variable bottom contours should be considered to provide deeper holes and flat
shallow benches. This feature will provide habitat for diversity of plants and wetland
inhabitants for wetland mitigation sites and stOlID water basins.
Section 4. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
sections to be numbered 19-200 through 19-208, which shall read as follows:
ARTICLE VIII. SURFACE WATER MANAGEMENT UTILITY.
Sec. 19-200. Surface water management utility established.
Surface water management shall be operated as a public utility pursuant to M.S. S
444.075.
Sec. 19-201. Definitions.
The following words, terms, and phrases, when used in this article, shall have the
meaning ascribed to them in this section, except where the context clearly indicates a
different meaning:
Surface water management budget is the annual budget approved by the city council for
surface water management including planning, monitoring, capital expenditures,
personnel, and equipment.
Surface water management fee means the quarterly charge for each parcel of nonexempt
property in the city for the management of surface water.
Utility factor means the ratio of runoff volume, in inches, for a particular land use, to the
runoff volume, in inches for a one-third-acre residential lot, assuming a two-inch rainfall
and soil conservation service (SCS) "type B" soil conditions.
Sec. 19-202. Surface water management fees.
(a) The utility factors for various land uses are as follows:
Land Use Utility
Classification Factor
1 Single-family and rural residential 1.00
2 Agricultural 1.00
3 Undeveloped 1.00
4 Medium density residential 2.24
5 High density residential, industrial, office, institutions, 3.34
(churches, schools, government buildings, hospitals)
6 Business/Commercial 4.28
7 Parks, cemeteries, golf courses, arboretum 0.45
18
I Parking lots as a principal use
16.14
(b) The surface water management fee for single-family residential property shall be
calculated as follows:
(1) Percentage of runoff in the city attributable to single-family residential property;
(2) Multiplied by an amount equal to 25 percent of the surface water management
budget;
(3) Divided by the estimated total acreage of single-family residential property in the
city; and
(4) Divided by three.
(c) The surface water management fee for each tax parcel classified 1,2, and 3 is the
single-family residential fee. The fee for classifications 4 through 8 shall be calculated as
follows: Fee for a single-family residential tax parcel multiplied by the utility factor
multiplied by the acreage of the parcel.
Sec. 19-203. Credits.
The city council may adopt policies for adjustment of the surface water management fees.
Information to justify a fee adjustment must be supplied by the property owner.
Adjustment of fees shall not be retroactive.
Sec. 19-204. Exemptions.
The following land uses are exempt from the surface water management fee:
(1) Public right-of-way.
(2) Lakes.
Sec. 19-205. Payment of fee.
Surface water management fees shall be involved quarterly. The amount due as shown on
the invoice shall be payable on or before the twentieth day of the month in which the
invoice is issued. A penalty of ten percent per quarter shall be added to all accounts that
are not paid in full by the due date. The penalty shall be computed on the unpaid balance
not paid by the due date at the time each quarterly statement is prepared. Any prepayment
or overpayment of charges shall be retained by the city and applied against subsequent
fees.
Sec. 19-206. Appeal of fee.
If a property owner or person responsible for paying the surface water management fee
believes that a particular fee is incorrect, such person may file a written appeal with the
city clerk. Appeals will be heard by the city council. No adjustment will be made to the
utility factor for property classifications 1,2, and 3.
Sec. 19-207. Certification of delinquent fees.
If a surface water management fee is not paid within three months after a billing is
issued, the city council may certify the amount due, together with penalties, to the county
auditor to be collected with other real estate taxes on the parcel.
Sec. 19-208. Surface water management fund.
A separate fund shall be maintained for surface water management fees and expenditures.
Section 5. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _,200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
(Published in the Chanhassen Villager on
)
CITY OF CHANHASSEN
CARVER AND HENNEPIN COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 20
CHANHASSEN CITY CODE, ZONING
THE CITY COUNCIL OF THE CITY OF CHANHASSEN, MINNESOTA ORDAINS:
Section 1. Sections 20-401 through 20-418 of the City Code, City of Chanhassen,
Minnesota, are hereby repealed.
Section 2. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
sections to be numbered 20-401 through 20-421, which shall read as follows:
ARTICLE VI. WETLAND PROTECTION.
Sec. 20-401. Findings intent; rules adopted by reference.
(a). Wetlands help maintain water quality, serve to reduce flooding and erosion, act as
sources of food and habitat for a variety of fish and wildlife, and are an integral part of
the community's natural landscape. Wetlands provide the aesthetic benefits of open space
and can be used to provide a natural separation of land uses. It is the intent of this
ordinance to establish a policy of sound stewardship through coordination of regulations
that conserve, protect, enhance, and result in the no net loss of these environmentally
sensitive resources. In addition, it is the intent of the city to promote the restoration of
degraded wetlands.
(b). The intent of this ordinance is to avoid alteration and destruction of wetlands. When
this is not feasible, mitigation must be provided to recreate the function and value of the
lost or altered wetlands.
(c). This ordinance is adopted in part to implement the Wetland Conservation Act of
1991, as amended (M.S. ~ 103F.612 et seq.), and the accompanying rules of the
Minnesota Board of Water and Soil Resources (Minnesota Rules Chapter 8420, as
amended).
(d). This ordinance incorporates by reference the act and the rules. Terms used in this
ordinance which are defined in the act or the rules have the meanings given there.
Sec. 20-402. Purpose.
The purpose of this ordinance is to assure the general health, safety, and welfare of the
residents through preservation and conservation of wetlands and sound management of
development by:
(1). Conducting an inventory and classification of all wetlands within the city and
maintaining a comprehensive set of official city maps depicting the approximate location
and extent of wetlands.
(2). Establishing wetland regulations that are coordinated with water quantity and water
quality goals and policies of the Chanhassen Surface Water Management Plan.
(3). Requiring sound management practices that will protect, conserve, maintain,
enhance and improve the functions and values of wetlands within the community.
(4). Requiring measures designed to maintain and improve water quality in streams and
lakes.
(5). Protecting and enhancing the scenic value of wetlands.
(6). Restricting, controlling and mitigating the harmful effects of development on
wetlands.
(7). Allowing only development that is planned to be compatible with wetland protection
and enhancement.
(8). Providing standards for the alteration of wetlands when alteration is allowed.
(9). Educating and informing the public about the numerous benefits and features of
wetlands and the impacts of urbanization.
(10). Obtaining protective easements over or acquiring fee title to wetlands as
appropriate.
Sec. 20-403. No net loss.
(a). To achieve no net loss of wetland, except as provided under sections 20-417 and 20-
418 of this ordinance or authorized by a wetland alteration permit issued by the city, a
person may not drain, grade, excavate, fill, bum, remove healthy native vegetation, or
otherwise alter or destroy a wetland of any size or type. Any alteration to a wetland
permitted by a wetland alteration permit must be fully mitigated so that there is no net
loss of wetlands.
(b). Wetlands shall be subject to the requirements established herein, as well as
restrictions and requirements established by other applicable city ordinances and
regulations. The wetland protection regulations shall not be construed to allow anything
otherwise prohibited in the zoning district where the wetland area is located.
(c). All activities within the City shall comply with the Wetland Conservation Act of
1991, as amended (M.S. ~ 103F.612 et seq.), and the accompanying rules of the
Minnesota Board of Water and Soil Resources (Minnesota Rules Chapter 8420, as
amended). Where the requirements of City Code differ from those requirements, the
more restrictive shall apply.
Sec. 20-404. Official wetland map.
(a). The City shall maintain the official City Wetland Inventory, which is hereby adopted
by reference. An electronic copy of this map shall be maintained on the City's
Geographic Information System (GIS) database, with both hard and electronic copies
being made available for public review upon request.
(b). The City Wetland Inventory shall identify each basin as one of four management
categories: Preserve, Manage 1, Manage 2, and Manage 3. These classifications will be
determined using Figure 1.1 "Wetland Management Classification Process Flowchart for
Basic Wetland Protection" from Minnesota Routine Assessment Method for Evaluating
Wetland Functions (MnRAM Version 3.0), or future versions.
(c). The presence or absence of a wetland on the City Wetland Inventory does not
represent a definitive determination as to whether a jurisdictional wetland that would be
covered by this ordinance is present. Wetlands identified during a site-specific
delineation, but not identified by the City Wetland Inventory, are still subject to the
provisions of this ordinance.
(d). The City Wetland Inventory does not depict delineated wetland boundaries and shall
not be used as such.
(e). The City Wetland Inventory shall be amended to include any wetlands discovered
during the site review process.
Sec. 20-405. Wetland delineation.
(a). It is the responsibility of the project applicant to determine whether a wetland exists
on a subject property. It is the responsibility of the applicant to complete a wetland
delineation and submit sufficient documentation of the wetland boundary to the city in a
Wetland Delineation Report. Wetland delineations shall be completed by, or under the
direct supervision of, a Certified Wetland Delineator. Three (3) hard copies of the
Wetland Delineation Report must be submitted to the city's WCA agent. Additionally,
an electronic copy of the delineated wetland boundaries must be submitted in a format
compatible with the city's GIS database. Wetland delineations shall be valid for three
years. Wetland delineations completed more than three (3) years prior may be confirmed
and/or updated by a qualified wetland professional through a site visit and submittal of a
summary of the findings, a copy of the old delineation and a map depicting both the
original and revised wetland boundaries, where applicable.
(b). Wetland delineations do not need to be completed for properties adjacent to a
proposed development that is under separate ownership. However, sufficient information
must be presented to demonstrate that any proposed activities shall not directly or
indirectly impact adjacent basins. The applicant shall review readily available
information including, but not limited to, the City Wetland Inventory, National Wetland
Inventory maps, topographic maps, soil survey maps, and recent and historic aerial
photographs in preparing this assessment.
Sec. 20-406. Wetland classification.
(a). All wetlands delineated under section 20-405 of this ordinance that have not been
previously classified shall be classified using the results from the Minnesota Routine
Assessment Method for Evaluating Wetland Functions (MnRAM Version 3.0), or future
verSIOns.
(b). A MnRAM shall be completed by the property owner or applicant for each
previously unclassified wetland. An electronic version of the MnRAM evaluation must
be submitted to and approved by the city to establish the classification of each wetland
prior to any alteration or impact to the wetland.
(c). MnRAM 3.0 assessments have been completed by the City as a component of the
City Wetland Inventory. Applicants; however, may appeal the determination, and submit
a request to change the classification. To do so, the applicant must submit an electronic
copy of the MnRAM for each affected basin to the WCA agent. The forms must be filled
out by a qualified wetland scientist. The WCA agent will consult with the technical
evaluation panel to determine if a change in the classification is warranted. In all cases,
the burden to demonstrate the need for a change in classification lies with the applicant.
Sec. 20-407. Permit required.
(a). No person shall drain, excavate in the permanent or semipermanent flooded areas of
open water wetlands, or fill a wetland, wholly or partially, or otherwise impact wetlands
without first having a wetland replacement plan or other determination approved by the
city. Draining, grading, excavating, filling, removing healthy native vegetation, or
otherwise altering or destroying a wetland of any size or type not subject to an exemption
under section 20-417 of this chapter requires a wetland alteration permit. Activity in a
wetland requiring a wetland alteration permit includes, but is not limited to:
(1). Construction of new streets and utilities.
(2). Creation of ponds or dams and alterations of the natural drainageways of water
courses. This shall only be allowed as part of a mitigation project, or to restore or
improve the function and value of the wetland.
(3). Installation of boardwalks and docks. Docks shall meet the additional
requirements in Chapter 6, Article II of the Chanhassen City Code.
(4). Discharge of untreated stormwater runoff into wetlands.
(5). Changes in wetland hydrology that result in an increase in the ordinary high
water level of a wetland by more than 12 inches.
(b). The city must be notified at least five business days prior to the use of any form of
treatment of wetlands to control nuisance vegetation including chemically treating,
burning, mowing or biologically treating wetlands.
(1). At the time of notification, a person or company will be required to supply the
following information:
a. Location of wetland;
b. Area of wetland to be treated;
c. Name, address and telephone number of the party responsible for treatment;
d. Name, address and telephone number of person or persons performing the
treatment;
e. Date of treatment;
f. A list of the type of treatments to be used at such time;
g. A statement indicating an understanding of the treatment being applied and its
effect on humans, plants and wildlife; and
h. A signed consent from all property owners owning property containing or
abutting wetland to be treated.
(c). The following activities shall be determined exempt from the provisions listed in
subpart (b) above:
(1) Federal, state or local government staff or contractors during the course of
conducting maintenance activities; and
(2) Metropolitan Mosquito Control District during the course of conducting mosquito
control acti vities.
Sec. 20-408. Exemptions from earth work permit requirements.
Earth work completed in accordance with an approved wetland alteration permit is
exempt from the requirement to obtain a separate earth work permit.
Sec. 20-409. Permit application requirements and decisions.
(a). A wetland alteration permit shall not be issued without having been first reviewed by
the planning commission and approved by the city council following the review and
hearing procedures set forth for conditional use permits and the additional requirement of
Minnesota Rules 8420.0230. The applicant shall have the burden of proving that the
proposed use or activity complies with the purposes, intent and other provisions of this
ordinance. The council may establish reasonable conditions which are specifically set
forth in the permit to ensure compliance with requirements contained in this ordinance.
Such conditions may, among other matters, limit the size, kind or character of the
proposed work; require the construction of other structures; require replacement of
vegetation and wetland functions and values; establish required monitoring procedures
and maintenance activities; stage the work over time; require the alteration of the site
design to ensure buffering; and/or require the provision of a performance security.
(b). Any projects seeking a wetland alteration permit subject to this ordinance will be
required to submit the following:
(1). A wetland alteration permit application
(2). A site/grading plan of the entire property
(3). Existing and proposed drainage areas to wetlands
(4). A wetland delineation report in accordance with section 20-405
(5). Wetland classification information in accordance with section 20-406 for each
wetland on property
(6). Buffer strip plan meeting the criteria of section 20-411 (c) and (d)
(7). Submittals required by the Wetland Conservation Act
(8). Topographic data
(9). Other information as required by the city
(c). Decisions made under this ordinance that fall under the authority of the Minnesota
Wetland Conservation Act may be appealed to the Minnesota Board of Water and Soil
Resources under Minnesota Rules 8420.0250, after administration appeal rights under the
official controls have been exhausted. Staff costs to the city associated with appeals shall
be borne by the applicant.
(d). The city council shall appoint a person to serve on a technical evaluation panel. The
person must be a technical professional with expertise in water resources management.
Decisions under this ordinance must not be made until after receiving the determination
of the technical evaluation panel regarding wetland public values, location, size, and/or
type if the city council, the landowner, or a member of the technical evaluation panel asks
for such determinations. This requirement does not apply to wetlands for which such data
is included in an approved comprehensive wetland management plan per Minnesota
Rules 8420.0240. The city council may seek and consider recommendations, if any, made
by the technical evaluation panel in making replacement plan decisions. Unless
otherwise designated, the city's representative on the technical evaluation panel shall be
the WCA agent.
(e). The applicant for a wetland alteration permit is responsible for obtaining all other
necessary permits including but not limited to those required by watershed districts,
Minnesota Department of Natural Resources, United States Army Corps of Engineers and
Minnesota Pollution Control Agency prior to commencement of the permitted work.
Sec. 20-410. General standards.
(a). The following standards apply to all lands within and abutting a wetland:
(1). Septic and soil absorption system must be a setback minimum of 75 feet from
the ordinary high water mark of the wetland.
(2). The lowest ground floor elevation of a principal structure is three feet above the
100-year flood elevation of the wetland.
(3). Access across a wetland shall be by means of a boardwalk or elevated structure
and only upon approval of a wetland alteration permit. Wetland crossings must also
be in conformance with all other state regulations.
(4). Docks and boardwalks shall be elevated a minimum of six inches above the
ordinary high water mark. Docks and boardwalks shall only be permitted to cross
wetlands in instances where a wetland is riparian to a lake.
(5). The erosion and sediment control goals and policies within the city's Surface
Water Management Plan shall be met.
(6). Stormwater runoff shall not be discharged into wetlands without water quality
pretreatment as prescribed by Chanhassen City Code.
(b). When a wetland alteration permit is issued allowing wetland alteration, the
following standards shall be followed:
(1). The alteration will not have a net adverse effect on the ecological and
hydrological characteristics of remaining wetland.
(2). It shall be located as to minimize the impact on vegetation.
(3). It shall not adversely change water flow.
(4). The size of the altered area shall be limited to the minimum required for the
proposed action.
(5). The disposal of any excess material is prohibited within remaining wetland
areas.
(6). The disposal of any excess material shall include proper erosion control and
nutrient retention measures.
(7). Alterations to any wetland area are prohibited during waterfowl breeding season
or fish spawning season, unless it is determined by the city that the wetland is not
used for waterfowl breeding or fish spawning.
(8). Alterations to wetland areas shall be mitigated in accordance with the
requirements of this ordinance if the activity results in a loss of wetland area and/or
function and value of the wetland.
(9). Dedicated buffers in accordance with section 20-411.
Sec. 20-411. Placement of structures.
(a). For lots created on or after (date of codification), a buffer strip shall be maintained
abutting all wetlands. All existing vegetation adjacent to a wetland shall be left
undisturbed and applied toward the buffer strip unless otherwise approved by the WCA
agent or city council. Buffer strip vegetation shall be established and maintained in
accordance with the following requirements. If the buffer strip is disturbed, native plant
species shall be selected from wetland and upland plants to provide diverse habitat for
various species of wildlife. Buffer strips shall be identified by permanent monumentation
acceptable to the city. A minimum of one wetland buffer monument is required per lot
abutting the wetland edge. The maximum spacing between monuments is 300 feet.
(b). The following table provides the minimum standards required for each wetland
classification.
Structure Setback Permanent Buffer Percent of Buffer
Wetland from Buffer Edge Strip~inimum Strip in Native
Classification (feet) Width (feet) Ve2etation
Preserve 50 50 100%
Manage 1 40 30 100%
Manage 2 40 25 Over 50%
Manage 3 40 20 Over 50%
I
I
I
aTher
31'
00' ~/W
I
I
I
I
I
I
I
EHT
MANAGE 3 WETLAND IllUSTRATION
BUFFER
I
r SETBACK
FROM WETl..A.ND
BUFFER
C 40'
\
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(c). For lots of record prior to (date of codification), the minimum buffer strip and
setback requirements shall comply with subparagraph (b) above. If buffer strips and
setbacks were approved as part of the subdivision, those standards shall prevail, except
that in no case shall structures be set back less than 40 feet from the wetland edge.
(d). The Planning Commission or City Council may approve variances from applicable
buffer strips and setback requirements if suitable hardship can be demonstrated. In these
instances, additional performance standards may be enforced to compensate for the
reduced buffer strip widths or setbacks.
(e). In addition to the requirements above, wetland buffer strips for wetland mitigation
areas and those counted as Public Value Credit (PVC) shall also conform to the minimum
standards as set forth by the Wetland Conservation Act.
(f). No structures are to be placed within the wetland setback.
(g). For any subdivision, the locations of buffer strips and wetland setbacks shall be
surveyed and recorded on the Property Title and Certificate of Survey. A Certificate of
Occupancy shall not be issued unless this task is completed and approved by City staff.
(h). Retaining walls may be located within wetland setbacks, but neither the walls nor
the land alteration that takes place as part of wall construction shall encroach into the
required buffer strips.
Sec. 20-412. Buffer strips required.
(a). Before release of final plat, the applicant must submit to the WCA agent a drainage
and utility easement for protection of the wetland and approved buffer strip. The
easement must describe the boundaries of the wetland and the wetland buffer strips
(b). Building structures, paving, mowing, introducing non-native vegetation, cutting,
filling, dumping, disposing of yard waste, fertilizing, or tampering with the monuments
within buffer strips is prohibited.
(c). Additional wetland impacts shall not be allowed for the creation of buffer strips.
(d). The use of meandering buffer strips to maintain a natural appearance is encouraged
(e). Where roadways are constructed next to a wetland, a buffer strip shall be maintained.
(f). Where acceptable natural vegetation exists in a wetland and adjacent buffer strip, the
retention of such vegetation in an undisturbed state shall be required unless the applicant
receives approval to replace such vegetation. A wetland and/or buffer strip has
acceptable vegetation if it is dominated by native tree, shrub, or grass species, and has not
been used for agricultural production in the last five years.
(g). The WCA agent may deny the use of existing vegetation for the use of buffer strips
if:
1. It is dominated by any species on the state noxious weed list as defined by
Minnesota Statutes, Section 18.76-18.88. These species include species such as
leafy spurge, spotted knapweed, purple loosestrife, and common and glossy
buckthorn;
2. It is present on unstable slopes, has significant bare soil, displays a history of
erosion problems, is prone to gully formation, or does not function for sediment
and nutrient removal;
3. Any areas were used for agricultural production in the last five years; or
4. The buffer strip is disturbed or altered.
(h). If an area is deemed to be unacceptable in its current state, wetland buffer
landscaping plan must be submitted to the WCA agent. This plan shall include at a
mInImum:
1. A plan sheet showing the proposed new buffer strip locations and any buffer
strips acceptable as existing. Existing buffer strips shall be identified and marked
to prevent accidental disturbances.
2. A specification as to what seed mixture will be used, or what trees and/or shrubs
will be planted and their locations.
3. A verification that all seed stock and tree species are native to Minnesota and are
of local ecotypes.
4. A detailed specification that identifies the project schedule, materials, installation
or seeding instructions, and costs.
5. A maintenance schedule that describes the activities that will occur for at least the
first two (2) years. This should include a schedule of mowing and spot spraying
for weeds if an area is seeded. Plans that call for periodic burning shall have
additional details and must have special permission prior to installation.
6. A detail of all Best Management Practices (BMPs) and erosion control plans.
7. A plan identifying the locations of buffer strip markers.
8. An electronic copy of plans in a format compatible with the City GIS database.
(i). The city may, at their discretion, require a cash escrow or letter of credit up to 110%
of the cost to reestablish the buffer strip should it not be successful, not be maintained, or
otherwise require city intervention to maintain the ordinance requirements.
Sec. 20-413. Wetland alteration.
(a). An applicant for a wetland alteration permit must demonstrate that the activity
impacting a wetland has complied or, through imposition of conditions of approval, will
comply with all of the requirements of the Wetland Conservation Act.
(b). A wetland alteration permit shall not be issued unless the proposed development
complies with this article.
(c). When a wetland alteration permit is issued allowing wetland alteration, the alteration
must be consistent with the city's Surface Water Management Plan and the Wetland
Conservation Act. The alteration shall not alter the hydrological patterns in the remainder
of the wetland, if a portion of the wetland remains, unless exempted under section 20-
417.
Sec. 20-414. Wetland management activities.
Prior to commencement of a wetland management activity, an administrative wetland
permit must be obtained for the activity in accordance with section 20-415.
Sec. 20-415. Administrative wetland permit.
(a). Applications for administrative wetland permits shall be made on a form supplied by
the city. A fee shall be paid as set forth in Chanhassen City Code. The WCA agent shall
review applications to ensure proposed activities are in compliance with the Wetland
Conservation Act and the requirements of this ordinance and are consistent with
approved and/or accepted wetland management practices.
(b). Activities for which administrative wetland permits are approved shall not contribute
to nuisances as defined in the Chanhassen City Code.
Sec. 20-416. Mitigation.
(a). Mitigation intent. Where a wetland alteration permit is approved and mitigation is
required pursuant to City Code and the Wetland Conservation Act, mitigation must result
in an improvement to the wetland function and value. Mitigation plans must address
water quality, improvement, and maintenance of preexisting hydrological balance and
wildlife habitat. The wetland function and value will include improvement of water
quality, maintaining hydrological balance, and provision of wildlife habitat. Mitigation
will be performed at ratios required by the Minnesota Wetland Conservation Act to
achieve replacement of the wetland function and value.
(b). Mitigation standards. The functions and values of mitigation wetlands shall be
achieved through wetland restoration, creation and/or enhancement. The mitigation
standards found in Minnesota Rules 8420.0550 shall be followed.
(1). Mitigation shall be subject to wetland setback and buffer strip requirements as
set forth in this ordinance.
(2). Mitigation shall at a minimum replace preexisting wetland function and
values through the ratios set forth in Minnesota Rules 8420.0541.
(3). Mitigation, through the buffer strip, shall provide landscaping for nesting and
food for wildlife habitat. The buffer strip shall provide for wildlife cover and
utilize a diversity of native flora (i.e., trees, shrubs, grasses, herbaceous plants) to
encourage wildlife diversity and provide visual variety.
(4). Wetland mitigation shall be undertaken on-site. If this is not feasible, then
mitigation may occur locally within the subwatershed. If this is not possible, then
mitigation may occur outside the subwatershed, elsewhere in the city. If
mitigation cannot be accomplished on site, or if the city deems it necessary to
perform mitigation off-site, then the applicant shall be responsible for providing
off-site mitigation within the major subwatershed, as designated by the Minnesota
Wetland Conservation Act, or purchasing wetland credits from the state wetland
bank.
(d). Construction management and long term wetland maintenance.
(1). The wetland alteration permit holder shall follow best management practices
to minimize direct impacts due to erosion and construction practices and to
safeguard wildlife habitat.
(2). The wetland alteration permit holder shall submit an annual report to the city
for replacement wetlands in Chanhassen. The purpose of the annual report is to
describe actual wetland management, restoration or creation activities completed
during the past year as well as activities planned for the upcoming year. The
annual report shall include all the information required of annual monitoring
reports by Minnesota Rules 8420.0620 subpart 2.
The wetland alteration permit holder shall submit annual monitoring reports as
required by Minnesota Rules 8420.0610. Submission shall continue for at least
five years or until the replacement wetland is deemed by the Technical Evaluation
Panel (TEP) to be fully functional. Where feasible, the city shall require the
wetland alteration permit holder to satisfy long-term management requirements.
(e). Mitigation Surety. To ensure that the proposed wetland replacement occurs, the city
shall hold either a cash escrow or letter of credit equal to 110% of the current value of
wetland credits on the open market. An additional escrow account shall be established to
ensure that the required monitoring occurs. The monitoring escrow shall be set at 110%
of the current average monitoring expense as performed by an independent consultant.
The monitoring and replacement escrows may be released incrementally as monitoring
and replacement are successfully completed. The remaining escrow amount will be
returned and the letter of credit terminated upon completion of the monitoring and
approval by the Technical Evaluation Panel (TEP). Any interest earned by holding of a
cash escrow shall be the property of the city.
(f). Within the Minnehaha Creek Watershed District, 1: 1 mitigation is required for
excavation within wetlands.
Sec. 20-417. Exemptions and no loss determinations.
(a). Activities exempted by Minnesota Rules 8420.0122 or determined to result in no net
loss of wetlands shall be exempted from the provisions of this ordinance. However,
certificates of exemption or no loss must be obtained from the city prior to starting work.
(b). A person conducting an activity in a wetland under an exemption shall ensure that:
(1). Appropriate erosion and sediment control measures are taken to prevent
sediment discharges from the site;
(2). The activity does not block fish activity in a watercourse; and
(3). The activity is conducted in compliance with all other applicable federal,
state, and local requirements, including best management practices as listed in
part 8420.0112, and water resource protection requirements established under
M.S. Ch. 103H.
Sec. 20-418. Variances.
Variances from the requirements of this ordinance may be granted in accordance with the
variance provisions of Article II, Division 3 of this chapter so long as the variances do
not violate the Wetland Conservation Act and rules adopted under the Act.
Sec. 20-419. Expiration and renewal of permit.
(a). Unless otherwise specified by the city council, the permittee shall begin and complete
the development authorized by the wetland alteration permit within one year after the
date the council approves the permit application.
(b). The permittee shall provide written notice to the city 24 hours prior to the
commencement and completion of the permitted project. No project shall be deemed to
have been completed until approved by the city after receipt of notice of completion.
(c). If the permittee fails to commence work within the time specified in this section, the
permit shall be void. The permittee may make a written application to the city council for
an extension of the time to commence work, but only if the permittee submits the
application prior to the date already established to commence work. The application of an
extension shall state the reasons the permittee requires an extension. If the council does
not extend the permit, the holder of the void permit may apply for a new permit.
Sec. 20-420. Inspection of work.
The city may cause inspection of work for which a wetland alteration permit is issued, at
the applicant's expense, to be made periodically during the course of such work and shall
cause final inspection to be made following the completion of the work.
Sec. 20-421. Enforcement procedures.
(a). Violation of this article, wetland protection, or of the terms of a permit issued
thereunder shall be a misdemeanor.
(b). Any person who alters a wetland in violation of this article shall apply for a wetland
alteration permit and shall pay a filing fee double the regular fee. The city council may
require the violator to restore the wetland or take other mitigative measures.
Section 3. Section 20-1060 (2) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Protect creek corridors, wetlands, and significant stands of mature trees through the use
of careful site design; protective easements; sensitive alignment and design of roadways
and utilities; incorporation of natural features; landscaping and massing of trees that
enhance existing natural features and views; and the practices delineated in the City's
Surface Water Management Plan.
Section 4. Section 20-1061 (2) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Preservation of the natural conditions found on each site to the greatest extent possible,
through minimized removal of trees and other vegetation and soil, minimized site
grading, and application of the practices found in the city's Surface Water Management
Plan.
Section 5. Section 20-1072 (a) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Where natural or existing topographic patterns contribute to the beauty or utility of a
development, they shall be preserved to the greatest extent possible. Modification to
topography will be permitted where and to the extent that it contributes to good design.
All topographic modifications shall adhere to the practices delineated in the city's Surface
Water Management Plan.
Section 6. Section 20-1085 (3) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Protect creek corridors, wetlands, and significant stands of mature trees through the use
of careful site design; protective easements; sensitive alignment and design of
roadways/access and utilities; incorporation of natural features; landscaping and massing
of trees that enhance existing natural features and views; and the practices delineated in
the city's Surface Water Management Plan.
Section 7. The City Code, City of Chanhassen, Minnesota, is hereby amended by adding
a section to be numbered 20-1408, which shall read as follows:
Sec. 20-1408. Impervious surfaces.
Creation of impervious surfaces within the bluff setback may contribute to bluff
instability due to increased runoff and/or erosion. Impervious surfaces are prohibited
within the bluff setback unless specifically authorized within this article.
Section 8. Section 20-1551 (a) of the City Code, City of Chanhassen, Minnesota, is
hereby amended to read as follows:
Protect the Bluff Creek Corridor, wetlands, bluffs, and significant stands of mature trees
through the use of careful site design, protective covenants, sensitive alignment and
design of roadways and utilities, incorporation of natural features, landscaping,
techniques outlined in the city's surface water management plan, and the practices
delineated in the city's Surface Water Management Plan.
Section 9. Section 20-1552 (b) of the City Code, City ofChanhassen, Minnesota, is
hereby amended to read as follows:
Preservation of the natural conditions found in the primary zone and to the greatest extent
possible, preserving significant resources and minimizing impacts in the secondary zone
through cluster development and other practices which minimize the removal of
vegetation, minimize site grading, and application of practices found in the city's Surface
Water Management Plan.
Section 10. Section 20-1556 of the City Code, City of Chanhassen, Minnesota, is hereby
amended to read as follows:
To the greatest extent possible, all development shall minimize the amount of impervious
surface by clustering development, using common access drives and utility corridors and
minimizing building footprint size. Roads, walkways, bike trails, and parking areas must
be designed parallel to natural contours with consideration to maintaining consolidated
areas of natural topography and vegetation. Management of surface run-off caused by
impervious cover shall be designed using practices delineated in the city's Surface Water
Management Plan.
Within the secondary zone of the BCD District, areas with average slopes exceeding 25
percent shall be preserved in their natural state and maintained as permanent open space.
Areas with average slopes less than 25 percent but greater than ten percent shall not
exceed an impervious surface coverage of 25 percent. Impervious coverage for areas
where average slopes are less than ten percent shall be governed by the underlying zoning
district.
Section 11. Section 20-1561 (b) of the City Code, City ofChanhassen, Minnesota, is
hereby amended to read as follows:
Where possible, any disturbances of natural habitat areas within the secondary zone shall
be avoided. Any alterations to the natural habitat within the secondary zone shall adhere
to the practices delineated in the city's Surface Water Management Plan.
Section 12. This ordinance shall be effective immediately upon its passage and
publication.
PASSED AND ADOPTED this _ day of _, 200_, by the City Council of
the City of Chanhassen, Minnesota
Todd Gerhardt, City Manager
Thomas A. Furlong, Mayor
(Published in the Chanhassen Villager on
)