1c-1) Halla's Great Plains Golf Estates Final Plat ApprovalCITY OF /C-)
CHANHASSEN
690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317
(612) 937 -1900 • FAX (612) 937 -5739
MEMORANDUM
TO: Don Ashworth, City Manager
FROM: Sharmin Al -Jaff, Planner II
DATE: June 21, 1995
SUBJ: Final Plat for Subdivision #86 -31 for Halla Great Plains Addition, Don Halla
On September 26, 1994, the City Council approved the preliminary plat for Subdivision #86-
31 for Great Plains Golf Estates as shown on the plans dated June 6, 1994, subject to the
following conditions:
1. All areas disturbed during site grading shall be immediately restored with seed and
disc - mulched or wood fiber blanket within two weeks of completing site grading
unless the city's (BMPH) planting fates dictate otherwise. All areas disturbed with
slopes of 3:1 or greater shall be restored with sod or seed and wood fiber blanket.
' This condition is still applicable.
2. The applicant shall work with the City in developing a landscaping reforestation plan
on the site. This plan shall include a list of all trees proposed to be removed and their
size. The vegetated areas which, will not be affected by the development will be
protected.,by,a conservation easement. The conservation easement shall permit
pruning, remc yal,of dead or diseased vegetation and underbrush. All healthy trees
over 6" caliper at" 4' height shall not be permitted to be removed. Staff shall provide a
' plan which shows the location of the conservation easement; and the applicant shall
provide the legal description. This plan shall include a list of all trees and size
proposed to be removed. The plan shall be submitted prior to final plat approval.
Staff shall review the need for screening long Lots 1, 2, 3, 4 and 5, Block 4 as it
relates to the existing single family homes to the south.
' Staff has met with the applicant on several occasions to discuss landscaping and
outline the City's expectations. The applicant has incorporated some berms and
' vegetation along the easterly and westerly edge of Hwy. 101. This buffer is well
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Halla's Great Plains Estates
June 21, 1995
Page 2
designed and meets the requirements of the city ordinances. The applicant must
proved additional three trees per lot from the city's approved tree selection list.
3. Lot 4, 5, 7, and 8 Block 3, shall be custom graded and shall provide a tree
preservation plan for staff approval prior to issuance of a building permit. Staff shall
have the right to require a change in house pad and location if it will result in saving
significant vegetation. A snow fence shall be placed along the edge of the tree
preservation easement prior to grading.
This condition still applies. The plans reflect a 60 foot wide easement running south
of Lyman Boulevard. We note that the lot and block numbers have changed from the
previous submittal. The revised lot and block numbers are Lots 2, 3, 5, and 6, Block
1.
4. Dead end access roads in excess of 150 feet in length shall be provided with
Chanhassen Engineering and Fire Department approved provisions for the turning
around of fire apparatus. The turning radius of a fire apparatus access road shall be
designed; shown on site plan; and, approved by the Chanhassen Engineering and Fire
Department.
This condition has been met. Columbine Trail and Hibiscus Trail will connect to the
existing gravel road looping the street system.
5. Fire apparatus access road shall be designed and maintained to support the imposed
loads of fire apparatus and shall be provided with a surface so as to provide all -
weather driving capabilities. The road shall be in place prior to construction of new
dwellings. This applies to homes which are in excess of 150 feet of State Hwy 101.
This condition has been met.
6. Street names:
a. Maple Court is not acceptable. The City already has 5 streets with "Maple" in
the name. I
b. The street between Hwy.
and Halla Nursery Vista.
Halla Vista Drive.
101 and County Road 14 is named both Birch Drive
The street must have only one name. Eliminate
C. Rename "Golf View Circle." Submit alternative name. I
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Halla's Great Plains Estates
June 21, 1995
' Page 3
The applicant has submitted revised street names that are acceptable. Halla Nursery
' Drive shall be labeled Halla Nursery Drive East for that portion lying east of Hwy.
101 and Halla Nursery Drive West for that portion running west of Hwy. 101.
' 7. Building Department conditions:
' a. Use Carver County licensed septic site evaluator.
This condition has been met.
b. Submit boring logs of borings done on each proposed ISTS site with a unique
identification for each to Inspections Division.
This condition still applies, however, it should be modified by adding the following
language " and indicate boring numbers for each site on the Site Grading, Drainage
' and Soil Erosion Plan.
C. Stake and identify proposed property lines, proposed ISTS sites and percolation
' and boring locations.
This condition needs to be modified to read as follow" Evaluate existing ISTS on lot
10, Block 1 and repair or replace the ISTS if it is a failing or noncomplying system.
Repair or replacement, if necessary, must be done on a acceptable ISTS site other than
the site currently labelled as the (SECONDARY) site. "
d. Provide a preliminary evaluation report on the ISTS sites from Resource
Engineering.
This condition has been met. As a result of the evaluation, this condition will be
modified to read " Plat Lot 1, Block 4, and Lot 1, Block 5, as outlots.
e. Revise the preliminary grading plan to show standard dwelling type
designations for proposed house pads.
' The changes have not been made in accordance with the city's Standard Dwelling
' Type Designation.
8. The applicant will need to provide revised detailed storm calculations for 10 and 100-
' year storm events and provide ponding calculations for storm water quality and
quantity ponds in accordance to the City's Surface Water Management Plan for the
City Engineer to review and approve. The applicant shall retain on site the
' predeveloped runoff rate as well as provided interim water quality and quantity ponds.
Halla's Great Plains Estates
June 21, 1995
Page 4
The applicant shall provide detailed pre - developed and post - developed storm water
calculations for existing and proposed storm water basins. In addition, water quality
pond design calculations shall be based on Walker's pondnet model.
This condition has been met.
9. The streets shall be constructed to the City's rural street section. Detailed construction
plans and specifications shall be submitted for review and formal approval by the City
Council in conjunction with final plat approval. The construction plans shall be
designed in accordance to the City's latest edition of standard specifications and detail
plates.
This condition is still applicable.
10. The applicant shall enter into a development contract with the City and provide the
necessary financial security to guarantee installation of the public improvements and
compliance with final plat conditions of approval.
This condition is still applicable.
11. The applicant shall meet wetland fill and wetland mitigation conditions as stated in the
Corps of Engineers Section 404 Permit. Mitigation work shall be implemented prior
to or concurrent with wetland fill activity or excavation in future phases of the project.
This condition is still applicable.
12. The applicant shall apply for and obtain permits from the appropriate regulatory
agencies, i.e. Watershed District, MWCC, Health Department, PCA, DNR, Army
Corps of Engineers, Carver County Highway Department and MnDOT and comply
with their conditions of approval.
This condition is still applicable. The applicant has submitted an application to the
DNR and MnDOT.
13. The appropriate drainage and utility easements shall be dedicated on the final plat for
all storm water drainageways and ponding areas lying outside the street right -of -ways.
The minimum easement width shall be 20 feet wide. Consideration should also be
given for access for maintenance of the storm water ponding areas. Outlot A shall be
platted as a lot and block.
This condition has been partially met. Outlot A on the preliminary plat contained the
existing nursery which is now being platted as Lot 10. The condition should be
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Halla's Great Plains Estates
June 21, 1995
' Page 5
modified by adding the following language: "A drainage and utility easements shall be
' dedicated on the final plat over Outlots A and B from the 910 contour on Outlot A
and the 908 contour on Outlot B.
14. The applicant's engineer shall develop a sediment and erosion control plan in
accordance with the City's Best Management Practice Handbook. The plan shall be
submitted to the City for review and formal approval.
' This condition has been met.
15. The grading plan shall be revised to relocate all berming outside street or trunk
highway right -of -ways. The berm shall be limited to 4 feet high with 3:1 slopes along
Trunk Highway 101 right -of -ways. In addition, the grading plan shall show all
proposed grading as a result of drainage improvements, street and house construction.
The applicant's engineer shall work with staff in developing a revised storm drainage
plan to accommodate plat revisions.
The grading plans show some revisions along the westerly edge of Trunk Hwy. 101,
' however, a berm is still proposed in the Trunk Highway 101 Right of Way, adjacent to
Lot 2, Block 1. These berms will need to be relocated in to the lot.
' 16. The lowest floor elevation of all buildings adjacent to storm water ponds or wetlands
shall be a minimum of three feet above the 100 -year high water level. All storm water
ponds shall have side slopes of 10:1 for the first ten feet at the normal water level and
no more than 3:1 slopes thereafter or 4:1 slopes throughout for safety purposes.
This condition has been met except on Lot 15, Block 1, adjacent to Pond "A."
' However, Creekwood Drive is lower than the lowest floor elevation proposed on Lot
15, Block 1, eliminating the flood potential. This condition therefore has been
modified.
17. The outlet from the existing pond behind the nursery shall be re- routed and directed
through Pond "B."
This condition should be modified to read, "The existing ponds and Pond B shall be
! combined when Lot 10, Block 1 further subdivides." Due to elevation differences, this
is not feasible at this time. However, when Lot 10, Block 1 subdivides, the two ponds
' should be consolidated into one.
18. Existing wells and septic systems on the site which are not to be utilized shall be
properly abandoned in accordance with City or State codes.
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Halla's Great Plains Estates
June 21, 1995
Page 6
This condition is still applicable.
19. The applicant shall be responsible for the appropriate storm water quality and quantity
fees based in accordance to the City's Surface Water Management Plan. The
requirement for cash fees in lieu of land or permanent pond construction shall be
based upon the schedule in accordance with the prescribed land use zoning.
This condition is still applicable. The SWMP connection fees will be calculated after
review and approval of the construction plans.
20. The applicant shall report to the City Engineer the location of any drain tiles found
during construction and shall relocate or abandon the drain tile as directed by the City
Engineer.
This condition is still applicable.
21. The developer shall convey to the City appropriate drainage and utility easements for
future construction of storm drainage infrastructures over Outlot D, Great Plains Golf
Estates.
This condition has been met.
22. Ponding facilities on the east side of Trunk Highway 101 will be considered after the
plat has been revised to accommodate staff changes in the plat's street and lot
configuration. The developer's engineer should also provide the City Engineer with
revised detailed storm sewer drainage calculations and discharge rates for the storm
drainage system on the east side of Trunk Highway 101 as a result of revising the plat.
This condition has been met.
23. The applicant shall modify the plans and incorporate the following safety
improvements:
a. The steep banks along the west side of Trunk Highway 101 lying south of the
nursery entrance create visibility problems for northbound traffic. The
applicant is also proposing to construct berms as required along Trunk
Highway 101. Staff recommends that the existing banks along Trunk Highway
101 be pulled back to improve sight lines and berming be restricted to a
minimum of 4 feet in height.
This condition has been met.
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Halla's Great Plains Estates
June 21, 1995
t Page 7
' This condition is still applicable.
24. The applicant shall be required to re- excavate all unacceptable materials in the ravine
' on Lot 3, Block 6 and backfill with engineered fill as well as replace the existing
storm drainage pipe (24 -inch CMP) with concrete pipe.
' This condition should be modified as follows: " The applicant shall be required to re-
excavate all unacceptable materials in the ravine on Lot 3, Block 6 and backfill with
engineered fill. The applicant shall provide the city engineer documentation that the
existing storm pipe (24" CMP) is structurally sound. If the city determines the pipe is
not structurally sound the applicant shall replace it with either PVC OR RCP.
I 25. The applicant's engineer should redesign the storm water basin (Pond "D ") to
accommodate the existing significant trees that are alive yet.
I This condition need to be modified to read " Pond D needs to be combined with Pond
E and the area used as Pond D retained for 100 year flood control."
26. The applicant shall provide for the future looping of the two street systems through
Outlot A from Golfview Circle or Golfview Court. Outlot A shall have no additional
access granted for TH 101.
' The condition needs to be modified. The revised plans show two street stubs on the
north and south of Lot 10, Block 2 (old Outlot A), to provide for the future connection
of Delphinium and Daylilly Lane. Lot 10, Block 2, shall have no additional street
access on to TH 101.
' 27. The plat shall be redesigned to provide full public street access to the properties south
of this development via two stub streets extended south from Halla Nursery Vista
b. The hill on Trunk Highway 101 just north of the intersection of Creekwood
'
Drive shall be lowered to improve sight distances. The current situation does
not meet MnDOT standards for sight distance at the posted speeds.
This condition has been deleted. Staff believes the grading improvements
proposed along TH 101 at Creekwood will improve sight lines.
' C.
Roadway alignments for Halla Nursery Vista and Trunk Highway 101 may
impose sight distance problems as well. This should be investigated and
documented by the applicant's engineer that the intersection meets MnDOT's
'
standards for the posted speeds.
' This condition is still applicable.
24. The applicant shall be required to re- excavate all unacceptable materials in the ravine
' on Lot 3, Block 6 and backfill with engineered fill as well as replace the existing
storm drainage pipe (24 -inch CMP) with concrete pipe.
' This condition should be modified as follows: " The applicant shall be required to re-
excavate all unacceptable materials in the ravine on Lot 3, Block 6 and backfill with
engineered fill. The applicant shall provide the city engineer documentation that the
existing storm pipe (24" CMP) is structurally sound. If the city determines the pipe is
not structurally sound the applicant shall replace it with either PVC OR RCP.
I 25. The applicant's engineer should redesign the storm water basin (Pond "D ") to
accommodate the existing significant trees that are alive yet.
I This condition need to be modified to read " Pond D needs to be combined with Pond
E and the area used as Pond D retained for 100 year flood control."
26. The applicant shall provide for the future looping of the two street systems through
Outlot A from Golfview Circle or Golfview Court. Outlot A shall have no additional
access granted for TH 101.
' The condition needs to be modified. The revised plans show two street stubs on the
north and south of Lot 10, Block 2 (old Outlot A), to provide for the future connection
of Delphinium and Daylilly Lane. Lot 10, Block 2, shall have no additional street
access on to TH 101.
' 27. The plat shall be redesigned to provide full public street access to the properties south
of this development via two stub streets extended south from Halla Nursery Vista
Halla's Great Plains Estates
June 21, 1995
Page 8
between Lots 4 and 5, Block 4 and Lots 1 and 2, Block 4 or Lots 2 and 3, Block 4 or
some other alternative acceptable to the city.
This condition has been met.
28. The applicant should provide documentation to the City and Carver County that
appropriate right -of -way has been dedicated with the final plat to achieve one -half of
the minimum 100 -foot wide corridor for County Road 14.
This condition is still applicable.
29. Access to the individual lots shall be limited to the interior streets and not from
County Road 14 or Trunk Highway 101.
This condition is still applicable.
30. The applicant shall revise the plat to align Birch Drive to be continuous with Foxford
Road at the intersection of County Road 14.
This condition has been met.
31. The final plat should show the new dedicated Trunk Highway 101 right -of -way.
This condition has been met.
32. Outlot A is currently used as the nursery business and should be platted into a lot and
block. The final plat should also rename Town Road to Creekwood Drive and show
Lot 1, Block 1 and Lot 1, Block 2 as a replat of Lots 2 and 3, Block 1, Great Plains
Golfview Estates.
This condition has been met.
33. Staff and applicant work together to make sure that the future road in the southeast
corner of the plat not infringe on the bluff and that it adheres to the new bluff
ordinance.
This condition has been met. The applicant has revised the plans and moved the road ,
further west, locating it at a distance that exceeds 200 feet from the bluff.
34. The plat shall maintain an average overall density of 2 1/2 acres, including the nursery ,
property, for Halla's Great Plains Golf Estates preliminary plat.
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Halla's Great Plains Estates
June 21, 1995
' Page 9
34. The plat shall maintain an average overall density of 2 1/2 acres, including the nursery
' property, for Halla's Great Plains Golf Estates preliminary plat.
u
r_j
This condition is still applicable.
35. The total number of lots shall not exceed 36 lots. This number includes the parcel
owned by Mark Halla, the nursery site, and all lots proposed for single family
development.
This condition is still applicable.
36. The applicant must report back to the City Council by December 1, 1994 showing that
substantial progress is being made towards final plat approval, and the final plat must
be completed by March 1, 1995 or the preliminary plat will be void and the applicant
will have to comply with the 1 unit per 10 acre density requirement.
This condition is being addressed with this submittal.
37. Park and trail dedication fees shall be paid in lieu of parkland or trail construction at
the time of building permit application.
This condition still applies.
38. The final plat shall exclude David Halla's property.
The revised plan has excluded David Halla's property.
The applicant is proposing to subdivide 102.7 acres into 33 single family lots. The property
is zoned A2, Agricultural Estate District. This plat was originally filed in December, 1986.
The density at that time was 1 unit per 2.5 acres. Since that time, city ordinances have
changed to permit 1 unit per 10 acres, although the minimum lot size may be as small as
15,000 square feet as long as septic and wells are accommodated on the lot. This
subdivision is being reviewed under the 1 unit per 2.5 acres based on extensions of the
preliminary plat by the City Council.
The average lot size is 94,320 square feet with a resulting gross density of 1 unit per 2.8
acres. The site is located north of Creekwood Drive, east and west of Highway 101, and
south of County Road 14 (Pioneer Trail). Access to the subdivision will be provided via
Highway 101, Creekwood Drive, and Pioneer Trail.
All of the proposed lots meet the minimum area, width, and depth requirements of the Zoning
Ordinance.
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Halla's Great Plains Estates
June 21, 1995
Page 10
The site has a dense concentration of mature trees on the north and northwest corner of the
site. The plans indicate that the majority of those trees will be saved. A 60 foot preservation
easement running parallel to Pioneer Trail. This easement will prevent any construction from
taking place and subsequently preserving the trees. There are trees scattered throughout the
site. The majority of these trees are nursery stock trees, hence, staff did not require the
applicant to show these trees on the plans. Only natural growth was required to be shown
and saved.
In summary, staff believes that the proposed subdivision will require revisions. We are
recommending that it be approved with conditions outlined in the staff report.
SURFACE WATER MANAGEMENT PLAN (SWMP)/DRAINAGE
The City has adopted a Surface Water Management Plan (SWMP) that serves as a tool to
protect, preserve and enhance water resources. The plan identifies, from a regional
perspective, the storm water quantity and quality improvements necessary to allow future
development to take place and minimize its impact to downstream water bodies. In general,
the water quantity portion of the plan uses a 100 -year design storm interval for ponding and a
10 -year design storm interval for storm sewer piping. The water quality portion of the plan
uses William Walker, Jr.'s Pondnet model for predicting phosphorus concentrations in shallow
water bodies. An ultimate conditions model has been developed at each drainage area based
on the projected future land use, and therefore, different sets of improvements under full
development were analyzed to determine the optimum phosphorus reduction in priority water
bodies. The development will be required to be constructed in accordance with the City's
Surface Water Management Plan.
The proposed grading and drainage plans show several drainage areas discharging at various
outlets around the plat. Staff would like to reduce the areas of ponding in order to reduce
pond maintenance in the future.
Pond A The design for Pond A needs to be reconfigured so that the inlet is on the opposite
end of the outlet allowing for maximum pretreatment before discharge downstream. The
pond should be a design standard of 65 to 75 percent phosphorus retention.
Ponds B and C Stormwater runoff from predeveloped areas E and F would be pretreated at
Pond B and stormwater runoff from H would be treated at Pond C. Staff recommends that
Pond C be eliminated as a water quality pond. This area should be set for a dry pond where
it would be used as an emergency storage area for 100 -year storm events. The drainage from
Raspberry Hill could be routed back toward Pond B with some extra cutting and filling of 2
to 4 feet. Most of the drainage from Delphinium Lane, except for the cul -de -sac, could also
be routed back toward Pond B. The area draining from the cul -de -sac will most likely
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Halla's Great Plains Estates
June 21, 1995
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building near Highway 101. This pond has a tributary drainage area of approximately 40
' acres. The storage volume is estimated at 2.1 acre feet with a normal water level of 919.0
and a high water level of 924.5. Pond BC -P7.1 will then drain through an open channel to
pond BC -P7.5 which is designed as a sediment/nutrient trap.
' Existing Pond The existing pond at the nursery (Lot 10, Block 1) should be analyzed for its
efficiency to treat the rest of the 40 acres coming from the golf course and the site, but not
treated at Pond B. The City will credit the applicant's SWMP fees for the additional wet
volume necessary to provide treatment from off -site areas. Because this pond is a part of the
' overall drainage system, the final plat shall dedicate a drainage and utility easement over the
pond.
' Northern Drainage The SWMP shows the northern portion of the site (postdeveloped
drainage areas I, O, G, and P) draining to an existing wetland, BC -P5.13 located north of
County Highway 14. According to the SWMP, the normal water level for this wetland is 876
and the high water level is 878.5. This basin is an existing ag/urban wetland, and therefore,
runoff from impervious areas should be pre - treated before it is discharged into the basin.
Since drainage areas I and G have a minimal amount of impervious area, they do not need
' pretreatment. However, areas from O and P have street and roof top area that must be
pretreated. The City would prefer to pretreat this drainage in the proposed ponding area north
of CSAH 14, however, the area is so minimal the applicant may prefer to pretreat the runoff
on -site. The pretreatment for this area is less than that of the other ponding areas. The City's
SWMP calls for 35 percent retention of phosphorus.
' Pond E The area east of Highway 101 should be designed to drain into Pond E for
pretreatment. This pond will have to be expanded to also retain the 100 -year storm event
since the runoff is directed straight into the ravine which is highly susceptible to erosion.
' Staff recommends that Pond D be combined with Pond E and the area should be set for a dry
pond where it would be used as an emergency storage area for 100 -year storm events.
1 Storm Water Quality Fees
The SWMP has established a water quality connection charge for each new subdivision based
on land use. Dedication shall be equal to the cost of land and pond volume needed for
treatment of the phosphorus load leaving the site. The requirement for cash in lieu of land
and pond construction shall be based upon a schedule in accordance with the prescribed land
use zoning. Values are calculated using market values of land in the City of Chanhassen plus
' a value of $2.50 per cubic yard for excavation of the pond. The City has had discussions
with the applicant's engineer on the water quality ponding. The proposed SWMP water
quality charge of $800 /acre for single- family residential developments may be waived if the
' applicant provides water quality treatment according to the City's SWMP standards. Staff will
determine the applicant's SWMP fees after final review of the construction documents. The
final plans have not been submitted to staff for review and calculate the SWMP fees at time
Halla's Great Plains Estates
June 21, 1995
Page 12
of writing this report. Staff will be working with the applicant's engineer to bring the
construction plans and specifications and development contract for final approval at the July
10, 1995 City Council meeting.
Storm Water Quantity Fees
The SWMP has established a connection charge for the different land uses based on an
average city -wide rate for the installation of water quantity systems. This cost includes land
acquisition, proposed SWMP culverts, open channels and storm water ponding areas for
runoff storage. Single family residential developments will have a connection charge of
$1,980 per developable acre. The total gross area of the property is 102.74 acres; however,
12.03 acres is existing nursery and does not require SWMP fees. Therefore, 90.71 acres
results in a water quantity connection charge of $179,606. This fee will be due payable to the
City at time of final plat recording.
It appears that the pond north of the steep gully ravine on Outlot A is not wetland, but rather
a pond that was created for stormwater runoff. The area is to be excavated for additional
stormwater ponding. The Army Corps of Engineers should still be contacted to make sure
this excavation is exempt from their permit process.
The individual lots will be constructed with on -site septic systems in conjunction with the
individual home construction. The City's Building Department has performed the necessary
plan and specification review as well as inspections for each of these systems. The applicant
will be responsible for complying with the City standards as permitted through the City's
Building Department.
The plans show existing irrigation water lines through Lots 6, 7, 8 and 13, Block 1. All
irrigation lines will need to be abandoned or relocated along the common property lines to
avoid conflicts with home building.
Water service for the site is proposed to come from individual wells as the homes are
constructed. The applicant will be responsible for applying for and obtaining the necessary
permits through the City's Building Department. In addition, the applicant will need to
maintain the standards required by the State Health Department including on -going monitoring
and maintenance. Final detail street construction plans and specifications have not been
submitted to include with this approval process. The development contract and street
construction plans and specifications approval is scheduled for the July 10, 1995 City Council
agenda. The construction plans and specifications shall be prepared in accordance to the
latest edition of city standards for rural streets. Final plat approval should be contingent upon
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' Halla's Great Plains Estates
June 21, 1995
' Page 13
formal approval of the street construction plans. The applicant shall also be required to enter
' into a development contract with the City and provide the necessary financial security to
guarantee construction of the site improvements and conditions of final plat approval.
' STREETS/ACCE SS
The streets will have to be designed and constructed to meet the City's rural street standards.
' In the future when Lot 10, Block 1 further subdivides, Delphinium Lane should be extended
southerly to eventually connect to Daylilly Lane. A provision should be placed in the chain
' of title for all lots and development contract that Delphinium Lane and Daylilly Lane will be
extended in the future along with barricades and a sign indicating "THIS STREET SHALL
BE EXTENDED IN THE FUTURE ".
The plans propose accessing the southwesterly portion of the plat from Creekwood. The
plans propose construction of right turn lanes along TH 101 at the intersections of Halla
Nursery Drive and Creekwood. Staff believes that a right turn lane should also be included
along Pioneer Trail (County Road 14) at proposed Halla Nursery Drive. In addition, the
County has requested a 100 -foot wide street corridor along Pioneer Trail. The plat has not
provided documentation that the necessary right -of -way is being dedicated. A condition has
been added to insure the applicant dedicates one -half (50 feet) of the necessary 100 -foot wide
corridor.
' GRADING
The plans propose a berm within TH 101 right -of -way adjacent to Lot 2, Block 1. This berm
will need to be relocated onto Lot 2, Block 1. Site grading will be limited to the streets and
storm ponds.
EROSION CONTROL
An erosion control plan has been drafted and submitted to the City for review and approval
prior to construction commencement. Erosion control measures such as silt fence and/or hay
bales should be employed around culverts and ponding areas. The applicant's engineer should
' work with staff in modifying the erosion control plan to provide erosion control measures.
All construction access points shall be required to provide and maintain a rock construction
entrance until the streets are pave. Staff recommends the applicant use the City's Best
' Management Practice Handbook for erosion control measures.
All disturbed areas are to be seeded and mulched or sodded immediately after grading to
prevent erosion and sedimentation. Protection around ditch culverts such as hay bales or silt
fence is also required until the pavement is installed. If at all possible, construction of the
site in stages is highly recommended to help reduce erosion potential.
Halla's Great Plains Estates
June 21, 1995
Page 14
MISCELLANEOUS
A remnant parcel lies just west of the future TH 101 right -of -way on Lot 1, Block 3. This
parcel needs to be platted as an outlot.
The landscape plan needs to be revised. All landscaping shall be planted outside of all right -
of -ways.
PARK DEDICATION
Full park and trail fees will be collected per city ordinance in lieu of land acquisition and/or
trail construction.
COMPLIANCE WITH ORDINANCE - RSF DISTRICT
Lot
Lot
Lot
Home
Area
Width
Depth
Setback
Ordinance
15,000
90'
125'
30' front/rear
10' sides
BLOCK 1
Lot 1
61,899
239.14'
231.42'
Lot 2
165,677
200'
269.25'
Lot 3
108.907
200'
400'
Lot 4
74,591
199.6'
193'
Lot 5
83,323
110.64'
280'
Lot 6
94,978
116.25'
322.62'
Lot 7
59,040
137.31'
257.68'
Lot 8
64,593
263.90'
257.31'
Lot 9
56,477
400'
162'
Lot 10
523,970
860'
750'
t
Halla's Great Plains Estates
June 21, 1995
Page 15
Nursery Site
Lot 11
48,227
150.07'
253.83'
Lot 12
67,385
56.46'
240.66'
on curve
Lot 13
68,475
330'
290'
Lot 14
64,637
320'
290'
Lot 15
70,076
236.08'
290.21'
Lot 16
64,145
212.60'
230'
Lot 17
60,510
270.24'
220'
Lot 18
77,337
229.78'
290'
BLOCK 2
Lot 1
82,355
350'
286.67'
Lot 2
68,927
260'
267'
Lot 3
70,831
263.48'
274'
Lot 4
99,935
581.23'
300'
Lot 5
88,231
318.03'
271'
Lot 6
84,439
317.87'
266.82'
Lot 7
91,287
97.81'
254.46'
Lot 8
130,978
291'
293.99'
Lot 9
122,004
340'
375'
Block 3
Lot 1
122,360
255.73'
306.14'
Block 4
Lot 1
84,560
280'
310'
Halla's Great Plains Estates
June 21, 1995
Page 16
Lot 2 67,383 260' 260'
Outlot C 69,725
Block 5
Lot 1 72,152 73.01' 350'
on curve
Lot 2 89,310 292' 367'
Lot 3 126,204 300' 430'
Right of Way 376,745
Total site area 102.74 acres
RECOMMENDATION
Staff recommends the City Council adopt the following motion:
"The City Council approves the final plat for Halla's Great Plains Addition as shown on the
plans dated June 21, 1995 and subject to the following conditions:
1. All areas disturbed during site grading shall be immediately restored with seed and
disc - mulched or wood fiber blanket within two weeks of completing site grading unless
the city's (BMPH) planting dates dictate otherwise. All areas disturbed with slopes of
3:1 or greater shall be restored with sod or seed and wood fiber blanket.
2. The applicant must proved additional three trees per lot from the city's approved tree
selection list.
3. Lot 2, 3, 5, and 6 Block 1, shall be custom graded and shall provide a tree preservation
plan for staff approval prior to issuance of a building permit. Staff shall have the right
to require a change in house pad and location if it will result in saving significant
vegetation. A snow fence shall be placed along the edge of the tree preservation
easement prior to grading.
4. Building Department conditions:
a. Submit boring logs of borings done on each proposed ISTS site with a unique
identification for each to Inspections Division and indicate boring numbers for
each site on the Site Grading, Drainage and Soil Erosion Plan.
1
1
I
Halla's Great Plains Estates
June 21, 1995
Page 17
b. Evaluate existing ISTS on lot 10, Block 1 and repair or replace the ISTS if it is
a failing or noncomplying system. Repair or replacement, if necessary, must be
done on a acceptable ISTS site other than the site currently labelled as the
(SECONDARY) site.
C. Revise the preliminary grading plan to show standard dwelling type designations
for proposed house pads.
d. Discontinue nursery operations on all ISTS sites.
e. Protect ISTS sites as detailed in the June 12, 1995 letter to the applicant.
f. Relocate well on Lot 4, Block 2; Lot 9, Block 2 and Lot 2, Block 4.
5. The streets shall be constructed to the City's rural street section. Detailed construction
plans and specifications shall be submitted for review and formal approval by the City
Council in conjunction with final plat approval. The construction plans shall be
designed in accordance to the City's latest edition of standard specifications and detail
plates.
6. The applicant shall enter into a development contract with the City and provide the
necessary financial security to guarantee installation of the public improvements and
compliance with final plat conditions of approval.
7. The applicant shall meet wetland fill and wetland mitigation conditions as stated in the
Corps of Engineers Section 404 Permit. Mitigation work shall be implemented prior to
or concurrent with wetland fill activity or excavation in future phases of the project.
8. The applicant shall apply for and obtain permits from the appropriate regulatory
agencies, i.e. Watershed District, MWCC, Health Department, PCA, DNR, Army Corps
of Engineers, Carver County Highway Department and MnDOT and comply with their
conditions of approval.
9. The appropriate drainage and utility easements shall be dedicated on the final plat for
all storm water drainageways and ponding areas lying outside the street right -of -ways.
The minimum easement width shall be 20 feet wide. Consideration should also be
given for access for maintenance of the storm water ponding areas. Drainage and
utility easements shall be dedicated on the final plat over Outlots A and B from the 910
contour on Outlot A and the 908 contour on Outlot B.
10. The lowest floor elevation of all buildings except Lot 15, Block 1, adjacent to storm
water ponds or wetlands shall be a minimum of three feet above the 100 -year high
Halla's Great Plains Estates
June 21, 1995
Page 18
water level. All storm water ponds shall have side slopes of 10:1 for the first ten feet
at the normal water level and no more than 3:1 slopes thereafter or 4:1 slopes
throughout for safety purposes.
11. The existing ponds and Pond B shall be combined when Lot 10, Block 1 further
subdivides." Due to elevation differences, this is not feasible at this time. However,
when Lot 10, Block 1 subdivides, the two ponds should be consolidated into one.
12. Existing wells and septic systems on the site which are not to be utilized shall be
properly abandoned in accordance with City or State codes.
13. The applicant shall be responsible for the appropriate storm water quality and quantity
fees based in accordance to the City's Surface Water Management Plan. The
requirement for cash fees in lieu of land or permanent pond construction shall be based
upon the schedule in accordance with the prescribed land use zoning. The SWMP
connection fees for water quantity and quality have been estimated at $179,606 and will
be due to the City prior to recording the final plat. The final SWMP fees shall be
calculated after review of the construction plans.
14. The applicant shall report to the City Engineer the location of any drain tiles found
during construction and shall relocate or abandon the drain tile as directed by the City
Engineer.
15. The applicant shall modify the plans and incorporate the following safety
improvements:
a. Roadway alignments for Halla Nursery Vista and Trunk Highway 101 may
impose sight distance problems as well. This should be investigated and
documented by the applicant's engineer that the intersection meets MnDOT's
standards for the posted speeds.
16. The applicant shall be required to re- excavate all unacceptable materials in the ravine
on Lot 3, Block 6 and backfill with engineered fill. The applicant shall provide the
city engineer documentation that the existing storm pipe (24" CMP) is structurally
sound. If the city determines the pipe is not structurally sound the applicant shall
replace it with either PVC OR RCP.
17. Lot 10, Block 2, shall have no additional street access on to TH 101.
18. The applicant should provide documentation to the City and Carver County that
appropriate right -of -way has been dedicated with the final plat to achieve one -half of
the minimum 100 -foot wide corridor for County Road 14.
1
Halla's Great Plains Estates
June 21, 1995
Page 19
Li
1
19.
Access to the individual lots shall be limited to the interior streets and not from County
'
Road 14 or Trunk Highway 101.
20.
The plat shall maintain an average overall density of 2 1/2 acres, including the nursery
property, for Halla's Great Plains Golf Estates
preliminary plat.
'
21.
The total number of lots shall not exceed 36 lots. This number includes the parcel
owned by Mark Halla, the nursery site, and all lots proposed for single family
development.
22.
Park and trail dedication fees shall be paid in lieu of parkland or trail construction at
the time of building permit application.
23.
The streets and storm drainage system shall be constructed in accordance to the city's
rural street and utility standards. Detailed construction plans and specifications shall be
submitted for review and formal approval by the city council in conjunction with final
plat approval. The plans shall be designed in accordance with the latest edition of the
city's standard specifications and detail plates. Final plat approval is contingent upon
'
approval of the construction plans by the Chanhassen City Council.
24.
No berming or landscaping will be allowed within any right -of -way. The proposed
berm along TH 101 adjacent to Lot 2, Block 1 shall be relocated onto the lot.
25.
Grading Plan changes:
a. Pond A needs to be reconfigured so that the inlet is on the opposite end of the
outlet. The pond shall be designed to retain between 65% to 75% phosphorus
1
retention.
b. Pond C shall be revised from a water quality pond to a dry pond where it will
'
be used as an emergency storage area for a 100 -year storm events.
C. The drainage from Raspberry Hill and Delphinium Lane should be routed back
'
toward Pond B. This pond should also be designed to retain 65% to 75%
phosphorus retention.
'
d. The existing pond (Lot 10, Block 1) needs to be analyzed for its water quality
abilities. The applicant may receive credit towards their SWMP fees for any
additional wet volume necessary to provide treatment from the off -site areas
'
(golf course).
Li
1
Halla's Great Plains Estates
June 21, 1995
Page 20
e. Pond D shall be combined with Pond E to reduce the number of ponding areas.
Pond E will have to be expanded to also retain a 100 -year storm event since the
runoff from this pond is directed straight into the ravine which is highly
susceptible to erosion.
f. The final site grading, drainage and soil erosion control plan needs to be signed
by a professional engineer registered in the state of Minnesota.
g. All stormwater quantity ponds must have a stormwater outlet control structure.
h. The grading plan shall be revised to relate to the final plat lot and block
numbers.
i. Erosion control measures such as rock filter dikes shall be placed at drainage
swales prior to discharging off -site to maintain erosion. In addition, rock
construction entrances shall be employed and maintained at all access points
until the streets are paved.
j. Condition No. 3 on the erosion control notes should be modified to require the
site be fully revegetated and authorization by the City prior to the removal of
the erosion control fence.
26. All existing irrigation water lines need to be relocated or abandoned in areas where the
line encroaches through the platted lots with the exception of Lot 10, Block 1.
27. Final plat approval shall be contingent upon the City formally approving the street
construction plans and development contract.
28. Right turn lanes shall also be constructed on eastbound Pioneer Trail (County Road 14)
at Halla Nursery Drive.
29. The remnant parcel which lies west of the future TH 101 right -of -way (Lot 1, Block 3)
shall be platted as an outlot.
30. Future subdivision of Lot 10, Block 1 will require the extension of Delphinium Lane
South to connect eventually up with Daylilly Lane.
ATTACHMENTS
1. Memo from Steve Kirchman dated June 17, 1995.
2. Letter from Steve Kirchman dated June 12, 1995.
3. Memo from Dave Hempel and Diane Desotelle dated June 22, 1995.
4. Final plat dated June 21, 1995.
CITY OF
CHANHASSEN
690 COULTER DRIVE • P.O. BOX 147 0 CHANHASSEN, MINNESOTA 55317
(612) 937 -1900 • FAX (612) 937 -5739
MEMORANDUM
TO: Sharmin Al -Jaff Planner II
FROM: Steve A. Kirchman, Building Official.���
DATE: June 17, 1995
SUBJECT: #86 -31 SUB (Grate Plains Golf Estates, Don Halla)
I will be gone during most of the day on Monday through Thrursday of this week. I will be in
the office from 4:00 to 6:00 each day. These are my suggested revisions to the recemmended
conditions for Great Plains Golf Estates. This document is saved as:
G: \SAFETY \SAK \MEMOS \PLAN \HLA- GLF.SA5
6. Street names are acceptable as shown on Site Grading, Drainage and Soil Erosion
Plan dated may 26, 1995.
tee.
7.
1 0 . ♦.. - Gl1LVA1[i W V aiNi..V
Building Department conditions:
U se C C oun t y 1' d ptir •r 1
t� �'7� 1T�i'r GVUTTCT7ICG1T7�GC[ c — TG�7� LT�,�iiv ai��Qiuuc
yr.
Via. Submit boring logs of borings ' done on each proposed ISTS site with a unique
identification for each to Inspections Division and indicate boring numbers for
each site on the Site Grading, Drainage and Soil Erosion Plan.
Reason: Future indh dualISTS designs are permitted, in most cases,
to use existing borings in their designs. Accordingly, City
staff must be able to accurately determine which borings
Sharmin Al -Jaff
June 19, 1995
Page 2
staff must be able to accurately determine which borings
were done at which locations regardless of future
conditions.
Eb. St ake a nd identify propos pf l ines, pr ed 1STC s ites and pefe was
berg- te Evaluate existing ISTS on lot 10, Block 1 and repair or
replace the ISTS if it is a failing or noncomplying system. Repair or
replacement, if necessary, must be done on a acceptable ISTS site other than
the site currently labelled as the (SECONDARY) site.
Reason: Chanhassen City Code requires each lot have two ISTS
sites. Individual Sewage Treatment Systems Standards,
Chapter 7080, which is adopted by the City, requires
treatment of all sewage. Chanhassen City Code defines a
system not treating sewage as a failing system and requires
its repair or replacement.
4-.c. D.- ,,vide a .-ol;.Y.; a ..,7 Lien FOP O R t 18TS sires f em R
Engine°rifrt Plat Lot 1 Block 4 and Lot 1 Block 5 as outlots.
Reason: Evaluators were unable to locate acceptable ISTS sites on
Lot 1, Block 4, and ISTS sites on Lot 1. Block S were
destroyed.
d. Discontinue nursery operations on all ISTS sites.
Reason: Continued operations will destroy sites, creating
unbuildable lots.
e. Protect ISTS sites as detailed in the June 12, 1995 letter to the applicant.
Reason: Protection is required by Chanhassen City Code.
Protection as outlined in the letter offers a greater chance
of preventing damage during road construction and
expected continued nursery operations on permitted areas
of the property.
f. Relocate well on Lot 4, Block 2; Lot 9, Block 2 and Lot 2, Block 4.
Reason: Wells are located too close to proposed ISTS sites.
g.\safeq�ak'vm.-\plm\Ida- glf.m5
1
1
1 -,
1
I June 12, 1995
I F 7
u
Mr. Don Halla
Halla Nursery Inc.
10000 Great Plains Blvd.
Chaska, MN
Re: ISTS site protection
Dear Mr. Halla:
CITY OF
CHANHASSEN
690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317
(612) 937 -1900 • FAX (612) 937 -5739
I have received all the data necessary to review the
' Estates, and I am in the process of writing a memi
A copy of the memo will be available from the F
�I
U
'l
d ISTS sites for the proposed Great Plains Golf
to the Planning Department with my findings.
Department by June 20, 1995.
ISTS sites are required to be fenced off to prevent possible destruction.. A number of sites were destroyed
between April 17, 1995 and May 17, 1995, during the: removal of nursery stock. Consequently, all
remaining ISTS sites should be fenced off as soon as possible, and no later than City Council
consideration of the proposed subdivision on June 26, 1995. .1 will schedule an inspection of the sites on
June 26, 1995 at 9:00 AM to confirm all sites are fenced: undisturbed and located as shown on the
proposed final plat. The results of this inspection will be available immediately and will be relayed to
the City Council on the same evening.
I have enclosed a copy of the City policy ( #10 -1991) on fencing ISIS sites. Should you choose to protect
the sites with steel posts and rope as specified in item #6b, additional protection will be required. The
additional protection should. consist of snow fencing placed as shown on the enclosed copies of portions
of the 5/26/95 Site Grading, Drainage and Soil Erosion Plan. Approved signs should be installed on the
additional protection at 50 feet�on center _.
Sincerely,"
,
Steve A. Kirchman
Building Official
PC: Sharmin Al -Jaff, Planner II
Roger Anderson, Civil Engineer
PSD/ID file, #86 -1i (Great Plains Golf Estates)
enclosures: City Policy #10 -1991.
Copies of portions of 5/26/95 Site Grading, Drainage and Soil Erosion Plan (five sheets).
g.16a -glf3
CITY OF
CHANHASSEN
690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317
(612) 937 -1900 • FAX (612) 937 -5739
INSPECTIONS DIVISION POLICY
SEPTIC SYSTEMS
The following items are Inspections Division policies in regard to
septic systems within the City of Chanhassen.
1) Two sets
of the
design are required upon application for
building
permit.
Design sites must be
drawn to scale on
registered survey. Designs must include
the name, address,
telephone
number
and certification number
of the designer on
the first
page.
2) Systems must be designed b a designer licensed in Carver
County and must be approved I the Building Official prior to
issuance of building or septi=c permits.
3) Support Staff is responsible far confirming current licensing
of installer before issu=ing septic permit. Carver County
license required.
4) The permittee must perform the actual installation of each
septic system for which they were - .'issued a permit.
5) Primary and alternate septic sites must be individually
protected. Protection must remarxi around alternate site
during constructi=on on primary site's Protection must be re-
erected on primary site daily.
6) Protectlon- must cons -st. -o on.e -of the3 following:
a h'srro fenc2ngp- rauneir tex o -f.- _ sites
' w:.th approved signs securely attached.. apt 50' o. c.
x
b. 42 ni.gtr see -LA, fence pasts = ~at ` °50' 0. c. around
entire perimeter of 68th rtes with 2 horizontal
rows of 1/4" synthe=tic rope attached to each fence
post. Approved sxyns must be securely attached to
ropes at 50' o. c;
Inspections Division
Septic
Policy #10 -1991
Date: 01/24/91
4V Revised: 04/28/92
%0 PRINTED ON RECYCLED PAPERage 1 of 2
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CITY OF
CHANHASSEN
690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317
(612) 937 -1900 • FAX (612) 937 -5739
MEMORANDUM
TO: Sharmin Al -Jaff, Planner II
FROM: Diane Desotelle, Water Resources Coordinator ..�.w �..,
Dave Hempel, Assistant City Engineer
DATE: June 22, 1995
SUBJ: Halla Great Plains Addition - Final Plat
Project No. 95 -13
Upon review of the final plat drawings prepared by Egan, Field & Nowak, Inc. and the site
grading drainage and erosion control plan dated May 26, 1995 prepared by Roger A. Anderson
& Associates, Inc., we offer the following comments and recommendations:
The City has adopted a Surface Water Management Plan (SWMP) that serves as a tool to protect,
preserve and enhance water resources. The plan identifies, from a regional perspective, the storm
water quantity and quality improvements necessary to allow future development to take place and
minimize its impact to downstream water bodies. In general, the water quantity portion of the
plan uses a 100 -year design storm interval for ponding and a 10 -year design storm interval for
storm sewer piping. The water ;quality portion of the plan uses William Walker, Jr.'s Pondnet
model for predicting phosphorus concentrations in shallow water bodies. An ultimate conditions
model has been developed at each drainage area based on the projected future' land use, and
therefore, different sets of improvements under full development were analyzed to determine the
optimum phosphorus reduction in priority water bodies. The development will be required to be
constructed in accordance with the City's Surface Water Management Plan.
The proposed grading and drainage plans show several drainage areas discharging at various '
outlets around the plat. Staff would like to reduce the areas of ponding in order to reduce pond
maintenance in the future.
1
Mr. Don Halla
June 22, 1995
Page 2
' Pond A The design for Pond A needs to be reconfigured so that the inlet is on the opposite end
of the outlet allowing for maximum pretreatment before discharge downstream. The pond should
be a design standard of 65 to 75 percent phosphorus retention.
Ponds B and C Stormwater runoff from predeveloped areas E and F would be pretreated at Pond
B and stormwater runoff from H would be treated at Pond C. Staff recommends that Pond C be
eliminated as a water quality pond. This area should be set for a dry pond where it would be
used as an emergency storage area for 100 -year storm events. The drainage from Raspberry Hill
' could be routed back toward Pond B with some extra cutting and filling of 2 to 4 feet. Most of
the drainage from Delphinium Lane, except for the cul -de -sac, could also be routed back toward
Pond B. The area draining from the cul -de -sac will most likely receive efficient treatment as it
' flows toward CSAH 14. Pond B shall be a design standard of 65 to 75 percent phosphorus
retention.
The City's Surface Water Management Plan shows predeveloped drainage areas E, F, and G
draining to a future stormwater /sediment pond, BC -P7.1 located just east of the existing building
near Highway 101. This pond has a tributary drainage area of approximately 40 acres. The
storage volume is estimated at 2.1 acre feet with a normal water level of 919.0 and a high water
level of 924.5. Pond BC -P7.1 will then drain through an open channel to pond BC -P7.5 which
is designed as a sediment /nutrient trap.
Existing Pond The existing pond at the nursery (Lot 10, Block 1) should be analyzed for its
efficiency to treat the rest of the 40 acres coming from the golf course and the site, but not
treated at Pond B. The City will credit the applicant's SWMP fees for the additional wet volume
necessary to provide treatment from off -site areas. Because this pond is a part of the overall
drainage system, the final plat shall dedicate a drainage and utility easement over the pond.
Northern Drainage The SWMP shows the northern portion of the site (postdeveloped drainage
areas I, O, G, and P) draining to an existing wetland, BC -P5.13 located north of County Highway
' 14. According to the SWMP, the normal water level for this wetland is 876 and the high water
level is 878.5. This basin is an existing ag /urban wetland, and therefore, runoff from impervious
areas should be pre- treated before it is discharged into the basin. Since drainage areas I and G
t have a minimal amount of impervious area, they do not need pretreatment. However, areas from
O and P have street and roof top area that must be pretreated. The City would prefer to pretreat
this drainage in the proposed ponding area north of CSAH 14, however, the area is so minimal
' the applicant may prefer to pretreat the runoff on -site. The pretreatment for this area is less than
that of the other ponding areas. The City's SWMP calls for 35 percent retention of phosphorus.
Pond E The area east of Highway 101 should be designed to drain into Pond E for pretreatment.
This pond will have to be expanded to also retain the 100 -year storm event since the runoff is
' directed straight into the ravine which is highly susceptible to erosion. Staff recommends that
Mr. Don Halla
June 22, 1995
Page 3
Pond D be combined with Pond E and the area should be set for a dry pond where it would be
used as an emergency storage area for 100 -year storm events.
Storm Water Quality Fees
The SWMP has established a water quality connection charge for each new subdivision based
on land use. Dedication shall be equal to the cost of land and pond volume needed for treatment
of the phosphorus load leaving the site. The requirement for cash in lieu of land and pond
construction shall be based upon a schedule in accordance with the prescribed land use zoning.
Values are calculated using market values of land in the City of Chanhassen plus a value of
$2.50 per cubic yard for excavation of the pond. The City has had discussions with the
applicant's engineer on the water quality ponding. The proposed SWMP water quality charge of
$800 /acre for single - family residential developments may be waived if the applicant provides
water quality treatment according to the City's SWMP standards. Staff will determine the
applicant's SWMP fees after final review of the construction documents. The final plans have
not been submitted to staff for review and calculate the SWMP fees at time of writing this report.
Staff will be working with the applicant's engineer to bring the construction plans and
specifications and development contract for final approval at the July 10, 1995 City Council
meeting.
Storm Water Quantity Fees
The SWMP has established a connection charge for the different land uses based on an average
city -wide rate for the installation of water quantity systems. This cost includes land acquisition,
proposed SWMP culverts, open channels and storm water ponding areas for runoff storage.
Single family residential developments will have a connection charge of $1,980 per developable
acre. The total gross area of the property is 102.74 acres; however, 12.03 acres is existing nursery
and does not require SWMP fees. Therefore, 90.71 acres results in a water quantity connection
charge of $179,606. This fee will be due payable to the City at time of final plat recording.
WETLANDS
It appears that the pond north of the steep gully ravine on Outlot A is not wetland, but rather a
pond that was created for stormwater runoff. The area is to be excavated for additional
stormwater ponding. The Army Corps of Engineers should still be contacted to make sure this
excavation is exempt from their permit process.
UTILITIES
The individual lots will be constructed with on -site septic systems in conjunction with the
individual home construction. The City's Building Department has performed the necessary plan
and specification review as well as inspections for each of these systems. The applicant will be
11
Mr. Don Halla
June 22, 1995
Page 4
' responsible for complying with the City standards as permitted through the City's Building
Department.
The plans show existing irrigation water lines through Lots 6, 7, 8 and 13, Block 1. All
irrigation lines will need to be abandoned or relocated along the common property lines to avoid
conflicts with home building.
' Water service for the site is ro osed to come from individual wells as the homes are
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constructed. The applicant will be responsible for applying for and obtaining the necessary
permits through the City's Building Department. In addition, the applicant will need to maintain
the standards required by the State Health Department including on -going monitoring and
' maintenance. Final detail street construction plans and specifications have not been submitted
to include with this approval process. The development contract and street construction plans
and specifications approval is scheduled for the July 10, 1995 City Council agenda. The
' construction plans and specifications shall be prepared in accordance to the latest edition of city
standards for rural streets. Final plat approval should be contingent upon formal approval of the
street construction plans. The applicant shall also be required to enter into a development
contract with the City and provide the necessary financial security to guarantee construction of
the site improvements and conditions of final plat approval.
' STREETS /ACCESS
The streets will have to be designed and constructed to meet the City's rural street standards. In
the future when Lot 10, Block 1 further subdivides, Delphinium Lane should be extended
southerly to eventually connect to Daylilly Lane. A provision should be placed in the chain of
title for all lots and development contract that Delphinium Lane and Daylilly Lane will be
' extended in the future along with barricades and a sign indicating "THIS STREET SHALL BE
EXTENDED IN THE FUTURE ".
' The plans propose accessing the southwesterly portion of the plat from Creekwood. The plans
propose construction of right turn lanes along TH 101 at the intersections of Halla Nursery Drive
and Creekwood. Staff believes that a right turn lane should also be included along Pioneer Trail
(County Road 14) at proposed Halla Nursery Drive. In addition, the County has requested a 100 -
foot wide street corridor along Pioneer Trail. The plat has not provided documentation that the
necessary right -of -way is being dedicated. A condition has been added to insure the applicant
' dedicates one -half (50 feet) of the necessary 100 -foot wide corridor.
H
Mr. Don Halla
June 22, 1995
Page 5
GRADING
The plans propose a berm within TH 101 right -of -way adjacent to Lot 2, Block 1. This berm
will need to be relocated onto Lot 2, Block 1. Site grading will be limited to the streets and
storm ponds.
EROSION CONTROL
An erosion control plan has been drafted and submitted to the City for review and approval prior
to construction commencement. Erosion control measures such as silt fence and /or hay bales
should be employed around culverts and ponding areas. The applicant's engineer should work
with staff in modifying the erosion control plan to provide erosion control measures. All
construction access points shall be required to provide and maintain a rock construction entrance
until the streets are pave. Staff recommends the applicant use the City's Best Management
Practice Handbook for erosion control measures.
All disturbed areas are to be seeded and mulched or sodded immediately after grading to prevent
erosion and sedimentation. Protection around ditch culverts such as hay bales or silt fence is also
required until the pavement is installed. If at all possible, construction of the site in stages is
highly recommended to help reduce erosion potential.
MISCELLANEOUS
A remnant parcel lies just west of the future TH 101 right -of -way on Lot 1, Block 3. This parcel
needs to be platted as an outlot.
The landscape plan needs to be revised. All landscaping shall be planted outside of all right -of-
ways.
RECOMMENDED CONDITIONS OF APPROVAL
Staff has listed below additional conditions of approval that should be incorporated into the final
plat approval process.
1. The applicant shall be responsible for surface water management connection fees (SWMP)
The SWMP connection fees for water quantity and quality have been estimated at
$179,606 and will be due to the City prior to recording the final plat. The final SWMP
fees shall be calculated after review of the construction plans.
2. The streets and storm drainage system shall be constructed in accordance to the city's
rural street and utility standards. Detailed construction plans and specifications shall be
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Mr. Don Halla
June 22, 1995
Page 6
submitted for review and formal approval by the city council in conjunction with final
plat approval. The plans shall be designed in accordance with the latest edition of the
city's standard specifications and detail plates. Final plat approval is contingent upon
approval of the construction plans by the Chanhassen City Council.
3. No berming or landscaping will be allowed within any right -of -way. The proposed berm
along TH 101 adjacent to Lot 2, Block 1 shall be relocated onto the lot.
4. Grading Plan changes:
a. Pond A needs to be reconfigured so that the inlet is on the opposite end of the
outlet. The pond shall be designed to retain between 65% to 75% phosphorus
retention.
b. Pond C shall be revised from a water quality pond to a dry pond where it will be
used as an emergency storage area for a 100 -year storm events.
C. The drainage from Raspberry Hill and Delphinium Lane should be routed back
toward Pond B. This pond should also be designed to retain 65% to 75%
phosphorus retention.
d. The existing pond (Lot 10, Block 1) needs to be analyzed for its water quality
abilities. The applicant may receive credit towards their SWMP fees for any
additional wet volume necessary to provide treatment from the off -site areas (golf
course).
e. Pond D shall be combined with Pond E to reduce the number of ponding areas.
Pond E will have to be expanded to also retain a 100 -year storm event since the
runoff from this pond is directed straight into the ravine which is highly
susceptible to erosion.
f. The final site grading, drainage and soil erosion control plan needs to be signed
by a professional engineer registered in the state of Minnesota.
g. All stormwater quantity ponds must have a stormwater outlet control structure.
h. The grading plan shall be revised to relate to the final plat lot and block numbers.
Erosion control measures such as rock filter dikes shall be placed at drainage
swales prior to discharging off -site to maintain erosion. In addition, rock
Mr. Don Halla
June 22, 1995
Page 7
construction entrances shall be employed and maintained at all access points until
the streets are paved.
j. Condition No. 3 on the erosion control notes should be modified to require the site
be fully revegetated and authorization by the City prior to the removal of the
erosion control fence.
5. All existing irrigation water lines need to be relocated or abandoned in areas where the
line encroaches through the platted lots with the exception of Lot 10, Block 1.
6. The applicant shall contact the Army Corps of Engineers to verify that excavation of Pond
E is exempt from their permit process. Documentation from the Army Corps of
Engineers shall be supplied to the City prior to any construction activities commencing.
7. Final plat approval shall be contingent upon the City formally approving the street
construction plans and development contract.
8. Right turn lanes shall also be constructed on eastbound Pioneer Trail (County Road 14)
at Halla Nursery Drive.
9. The remnant parcel which lies west of the future TH 101 right -of -way (Lot 1, Block 3)
shall be platted as an outlot.
10. Future subdivision of Lot 10, Block 1 will require the extension of Delphinium Lane
South to connect eventually up with Daylilly Lane.
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