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4. Wetand ordinance 1 CITYOF 4 1 ; . 4 iv CHANHASSEN 1 - , • I 690 COULTER DRIVE • P.O. BOX 147 • CHANHASSEN, MINNESOTA 55317 (612) 937 -1900 • FAX (612) 937 -5739 Action by City Admintst?stot 'r 1 Er,E be PwA MEMORANDUM Aie'• 1 R. TO: Planning Commission r Si: i = --- "� a._ cd to Commissiori FROM: Jo Ann Olsen, Senior Planner .?:;)seis ----,.......- DATE: October 27, 1992 # a I 1 SUBJ: Wetland Ordinance 1 As part of the Surface Water Management Program, the city reviewed the existing wetland ordinance. For some time, the city has wanted to update the wetland ordinance and propose I changes where there have been weaknesses in its effectiveness. We also wanted to include "state -of- the -art" understandings of methods to improve wetland protection while taking a more reasoned approach. To begin the review of the wetland ordinance, a subcommittee was formed. I The subcommittee consisted of members of the Surface Water Management Program Task Force, members from the original Wetland Committee, who were responsible for the existing wetland ordinance, staff and the city's consultant, Frank Svoboda. Part of this process also included 1 having all of the city wetlands mapped. The wetland inventory was performed by two wetland experts hired by the city. Each wetland was located on the aerial/topography plans and then each wetland was site visited to locate the ordinary high water mark and to determine the 1 characteristics of the wetland. The draft wetland ordinance was completed by the subcommittee and then presented to the I SWMP Task Force for their comments. The draft being presented to the Planning Commission contains the most recent changes made by the SWMP Task Force. The proposed wetland I ordinance has also been reviewed by the City Attorney. The draft wetland ordinance is attached to this cover memo and should be reviewed in detail. I What is being proposed, in certain aspects, has not been done before, and as a result we are once again at the forefront of wetland protection. During this whole process, we have worked with the new state law (Wetland Conservation Act - WCA) and what the regulatory rules may be. We I have also used the knowledge of wetland experts to incorporate new means of protecting wetlands. The new state law and rules are not yet finalized and may be significantly revised. The changes could result in the addition of regulatory agencies having a say in local wetland 1 enforcement. Our ordinance is consistent with the intent of the law and many of its provisions. 1 tle ft PRINTED ON RECYCLED PAPER 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 Planning Commission October 27, 1992 ' Page 2 Depending upon what is finally adopted, we may need to amend the ordinance at some point in ' the future. For the interim, we believe it is very important to adopt our ordinance and show that local governments can effectively administer wetland regulations. The following is a summary of some of the major changes to the wetland ordinance. ' 1. CHANGE THE CLASSIFICATION OF WETLANDS. ' Currently, our wetland ordinance has two classifications of wetlands; Class A (types 3 -8, Circular 39) and Class B (types 2, Circular 39). Essentially, Class B wetlands were allowed to be altered with mitigation and Class A wetlands were typically required to remain untouched. One of the problems with just the two classifications was that the wetlands were not just "good" or "bad" wetlands. Also, many times a Class B wetland would be allowed to become a storm water pond, but still be under wetland regulations. This caused several problems and misunderstandings. ' What we are proposing is three classifications of wetlands; Pristine, Natural and Ag/Urban. We have also added a definition of utilized which is not protected as a wetland. ' Pristine - High valued wetlands which have few visible signs of significant impact by agriculture or urbanization. Pristine wetlands are considered to be areas which all development is prohibited and for which the greatest amount of protection will ' be provided. Should not receive untreated surface water drainage. • Natural - High to moderate valued wetlands that have suffered from some impact but which offer or can be improved to offer high wetland values and functions. May be impacted by development only when the city finds there to be no reasonable or prudent alternatives. Wetland mitigation must be designed to offer improved value and function. Should not receive additional amounts of untreated surface water drainage from projects being considered for approval. t • Ag/Urban - Moderate to low valued wetlands. May be impacted by development contingent upon the provision of mitigation/replacement plans. The city encourages the provision of replacement/mitigation plans that serve to improve value and function to allow reclassification to natural wetland status. May directly receive surface water drainage. • Utilized - Utilized water bodies created for the specific purpose of surface water runoff retention and/or water quality improvements. These water bodies are not to be classified as wetlands even if they take on wetland characteristics. Wetland alteration permits shall not be required to undertake work on these water bodies. These definitions of wetlands fit in with how we have been working with wetlands. A pristine wetland is a unique and rare wetland which under no means should be altered. The city has two pristine wetlands located near the old Assumption Seminary. These wetlands will have increased 1 1 Plannin g Commission 1 October 27, 1992 Page 3 1 setbacks, buffer strips and now that we know where they are, we can influence off -site impacts. A natural wetland is what we have in the past called "good" wetlands with little or no previous 1 alteration and ones which should be protected. An ag/urban wetland is similar to the Class B wetland, one which has experienced alteration, and has the potential to either be improved to a Natural classification, is a good candidate for a storm water pond with reclassification to utilized or can remain as is. The fourth classification is utilized. This classification is not a wetland, but rather a storm water pond or some other similar use. A utilized water body will not be protected as a wetland with a setback, buffer strip and regulated uses. We have added this classification to prevent the problems we have had in the past with wetlands being altered to accommodate storm water retention yet still having to meet the wetland regulations. We also have cases where storm water ponds are created and then take on wetland characteristics. There were misunderstandings whether these ponding areas should now be protected as a wetland. This prevented the ponding areas from being maintained without complications. The four classifications will simplify enforcement of wetland regulations and should be easily understandable to all who are involved. These definitions can also be translated into the "circular 39" and cowardin wetland classification system used by other agencies. The wetland inventory provides one of the four designations for each wetland. The wetland maps and informational sheets will be available at the Planning Commission meeting. We suggest that you find a wetland near you and see what you think it should be and then we will look at it at the Planning Commission meeting. 2. WETLAND BUFFER STRIPS AND SETBACKS 1 Currently, the wetland ordinance requires a 75' setback for structures. There is no regulation on what can take place within the 75' setback. One of the problems we have had with the current wetland ordinance is that we could require a structure to be 75' from a wetland edge, but the area within the setback could be altered (such as a manicured lawn area) so that the wetland was not 1 really being protected. One of the ways we felt could improve this situation was to require an undisturbed buffer area around the wetland. A buffer strip would provide habitat and food for wildlife and would provide an additional "trap" for sediment and nutrients. The buffer strip is being required in addition to the setback. Staff felt the setback could be reduced from 75' since we will now be getting a buffer strip which will better protect the wetland than just a setback. The setback and buffer strip are different for each classification of wetland. There is also a requirement for all or a portion of the buffer strip to be vegetated with native vegetation, if such does not already exist. 1 1 1 1 1 Planning Commission October 27, 1992 1 Page 4 I Pristine Natural ARJUrban Utilized Structure Setback 100' 40' 40' 0' I measured measured from the from the , outside edge outside edge I of the buffer of the buffer yard* yard* 1 Buffer Strip* 20 -100' 10 -30' 0 -20' 0' Buffer Strip 1 Minimum Average Width 50' 20' 10' 0' 1 % of Native entire entire optional optional Vegetation ** in Buffer 1 Strip I * The dimensions of the buffer strips shall be determined by the city based upon the quality of the wetland, local topographic conditions and the type and design of development being proposed. The table above provides minimum and maximum dimensions for the I buffer strip. The use of a meandering buffer strip to maintain a natural appearance, is encouraged. Structure setbacks are also described in the table. On single family subdivisions in the RSF district, the applicant must demonstrate that each lot provides I sufficient area to accommodate the applicable front yard setback, 60' x 60' building pad, and a 30 foot rear yard area. All of these elements must be provided outside of designated wetland and buffer strip areas. 1 ** Native Vegetation: Restore disturbed areas in appropriate native ecosystem including native trees and 1 shrubs. 4. For development approved prior to (date of ordinance adoption) within 1 wetland areas and for lands abutting a wetland area, the following minimum provisions are applicable unless alternative plans are approved by the city under a wetland alteration permit: 1 1 1 1 Plannin g Commission I October 27, 1992 Page 5 1 TABLE OF WETLAND CLASSIFICATIONS 1 Pristine Natural AQ/Urban Utilized 1 Setback 1 Principal 100' 75'* 75' 0' Structure I For development approved prior or to the adoption of the new wetland ordinance, the existing setback of 75' with, no buffer strip, is required (except for pristine wetlands). 3. MITIGATION The current ordinance does not address mitigation. We have always required mitigation on at I least a one to one ratio for any alteration approved as part of the wetland alteration permit. The mitigation required by the city always resulted in a wetland of equal or better function and value. I In doing, this Chanhassen was ahead of its time. Although the verdict is still out on what type of mitigation is the best (and if any mitigation actually "replaces" a natural wetland) a lot of progress has been made with mitigation. The new state law (WCA) is also influencing mitigation I requirements. We have addressed the new wetland technology and the new state law requirements. Currently, the interim state law requires a one to one ratio in area for mitigation. With the implementation of the final rules, this could be changed to two to one. What we have done in the past, and want to continue to do, is to not just look at mitigation in area but to take function I and value into consideration. Any mitigation must result in an improvement to the wetland function and value. Mitigation will not always be based solely on an acre to acre replacement, but may be based on replacement of habitat units (HU) through the use of habitat evaluation 1 procedures (see attached). If significant improvements in the wetland value and function result, acre for acre surface area replacement may not be required. The wetland ordinance also goes into detail on mitigation standards and techniques. 1 4. MISCELLANEOUS There have been several changes to the format of the ordinance to make it more understandable. We have emphasized our intent to "avoid ", "minimize" and "mitigate ". This is referred to as "sequencing" of wetland impact decisions under the state law. 1 1 1 1 1 Planning Commission October 27, 1992 I Page 6 I PLANNING COMMISSION UPDATE The Planning Commission reviewed the proposed wetland ordinance on November 4, 1992. The Planning Commission recommended a few minor changes to the ordinance and then unanimously recommended approval of the wetland ordinance. The changes recommended by the Planning Commission are included in the attached draft for City Council review. 1 RECOMMENDATION I Staff recommends the City Council approve first reading of the Wetland Ordinance as shown in Attachment #1. 1 Attachments 1. Wetland Ordinance dated November 17, 1992 1 2. Planning Commission minutes dated November 4, 1992 1 1 1 1 1 1 1 1 1 1 i CITY OF CHANHASSEN CARVER AND HENNEPIN COUNTIES, MINNESOTA ORDINANCE NO. ' AN ORDINANCE AMENDING CHAPTER 20 OF THE ' CHANHASSEN CITY CODE CONCERNING WETLANDS THE CITY COUNCIL OF THE CITY OF CHANHASSEN ORDAINS: Section 1. Chapter 20, Article VI of the Chanhassen City Code is amended in its entirety to read: ARTICLE VI. WETLAND PROTECTION Sec. 20 -401. FINDINGS AND INTENT. (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 Article to establish a policy of sound stewardship through coordination of regulations which 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 Article is to avoid alteration and destruction of wetlands. When this is not feasible, mitigation must be provided to recreate the lost or altered wetlands value and function. Sec. 20 -402. PURPOSE. The purpose of this Article 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 all wetlands within the City and maintenance of a comprehensive set of official City maps delineating wetlands. (2) Establishment of wetland regulations that are ' coordinated with flood protection and water quality programs under the Chanhassen Surface Water Management Plan. 1 (3) Requiring sound management practices that will protect, conserve, maintain, enhance, and improve the present quality of wetlands within the community. 263 r11/17/92 ' 1 (4) Requiring measures designed to maintain and improve water quality in streams and lakes. 1 (5) Protecting and enhancing the scenic value of wetlands. (6) Restricting and controlling the harmful effects of land 1 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) Mitigating the impact of development adjacent to wetlands. 1 (10) Educating and informing the public about the numerous benefits and features of wetlands and the impacts of urbanization. (11) Obtaining protective easements over or acquiring fee title to wetlands as appropriate. Sec. 20 -403. DELINEATION OF WETLANDS. ' 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. A wetland is land that meets the definition of "wetlands" set forth in this Ordinance. Wetland boundaries and wetland types as established by officially adopted City maps shall be prima facie evidence of the location and type of wetland. The official maps shall be developed and maintained by the Planning Department. If an applicant questions whether a wetland exists or disputes its delineation, the applicant shall have the burden to ' supply detailed information for review supporting the applicant's position. The applicant shall provide appropriate technical information, including but not limited to, topographical survey 11 and soil data deemed necessary for the City to determine the exact wetland boundary. The Planning Director shall make a determination to maintain the officially designated wetland 11 boundary or if the boundaries need to be corrected on City plans and maps based upon the data that is supplied. Data for wetland determination shall be certified by a registered engineer, surveyor, or a qualified wetland consultant. The applicant may appeal the Planning Director's determination of the wetland boundary and type to the City Council. This Article establishes three (3) wetland types and one body type: 263 2 r11/17/92 1 Wetlands. Ag /Urban. Wetlands that have been influenced by agricultural or urban (residential, commercial, or industrial) land usage are called Ag /Urban. Influences include: over nutrification, soil erosion and sedimentation, and water quality degradation. As 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. Wetlands. Natural. Natural wetlands are still in their natural state and typically show little sign of impact from surrounding land usage. The vegetative community of these wetlands are 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. Wetlands, Pristine. Wetlands that exist in a natural state and have special and unusual qualities worth protecting at a high level are called Pristine. These qualities include: outstanding vegetation community, native species population, rare or unusual species present, and habitat for rare wildlife species. Utilized. Utilized water bodies created for the specific purpose of surface water runoff retention and /or water quality improvements. These water bodies are not to be classified as wetlands even if they take on wetland characteristics. Wetland alteration permits shall not be required to undertake work on these water bodies. , Sec. 20 -404. NO NET LOSS. To achieve no net loss of wetland, except as provided under 1 Section 20 -416 of this Ordinance, or authorized by a wetland alteration permit issued by the City, a person may not drain, grade, 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, will be fully mitigated so that there is no net loss of wetlands. Sec. 20 -405. STANDARDS. The following standards apply to all lands within and abutting a wetland: (1) Septic and soil absorption system must be a setback minimum of one hundred fifty (150) feet from the ordinary high water mark of the wetland. (2) The lowest ground floor elevation is three (3) feet 1 above ordinary high water mark of the wetland. (3) Docks or walkways shall be elevated six (6) to eight (8) inches above the ordinary high water mark or six 263 3 r11/17/92 1 II 1 (6) to eight (8) inches above the ground level, whichever is greater. 1 (4) Access across a wetland shall be by means of a boardwalk and only upon approval of a wetland alteration permit. 1 (5) The City's Best Management Practices Handbook shall be followed. II Sec. 20 -406. WETLAND BUFFER STRIPS AND SETBACKS. (a) For development approved after (date II of ordinance adoption), a buffer strip shall be maintained abutting all wetlands. Buffer strip vegetation shall be established and maintained in accordance to the following I requirements. Plant species shall be selected from wetland and upland plants to provide habitat for various species of wildlife. Buffer strips shall be identified by permanent monumentation II acceptable to the City. In residential subdivisions, a monument is required for each lot. In other situations, a monument is required for each 300 feet of wetland edge. The buffer strips and structure setbacks shall meet the following standards: II Wetland Type Pristine Natural Act /Urban Utilized II Principal 100' 40' 40' 0' Structure measured measured Setback from the from the 11 outside edge outside edge of the of the buffer strip* buffer strip* II Buffer II Strip 20 -100' 10 -30' 0 -20' 0' Buffer Strip I Minimum Average Width 50' 20' 10' 0' 1 % of Native Vegetation in Buffer Strip Entire Entire Optional Optional II II II 263 4 r11/17/92 II 1 AG /URBAN WETLAND ILLUSTRATION BUFFER 7 1 ( s - 1 :/ VIEnAND ( 00'11/W I HOME FRONT YARD I BUFFER SEM 40' ) ( I 1 10' 1 I 1 0' EA WETLAND BUFFER STRIP (MIERAGE 10' DEPTH) 1 The dimensions of the buffer strips may be adjusted by the City 1 based upon the quality of the wetland, local topographic conditions, and the type and design of development being proposed. The table above provides minimum and maximum dimensions 1 for the buffer strip. The use of a meandering buffer strip to maintain a natural appearance, is encouraged. Structure setbacks are also described in the table. On single family subdivisions in the RSF district, the applicant must demonstrate that each lot provides sufficient area to accommodate the applicable front yard setback, 60 x 60' deep building pad, and a thirty (30) foot rear yard area. All of these elements must be provided outside of designated wetland and buffer strip areas. (b) For development approved prior to (date of ordinance adoption) within wetland areas and for lands abutting a wetland area, the following minimum provisions are applicable unless alternative plans are approved by the City under a wetland alteration permit: Pristine Natural Ag /Urban Utilized Setback Principal 100' 75' 75' 0' Structure 1 The City may approve reduced wetland setbacks as outlined in subparagraph (a) above. 1 263 5 r11/17/92 1 1 Sec. 20 -407. WETLAND ALTERATION. An applicant for a wetland alteration permit shall adhere to 1 the following principles in descending order of priority: (1) Avoiding the direct or indirect impact of the activity that may destroy or diminish the wetland; (2) Minimizing the impact by limiting the degree or 1 magnitude of the wetland activity and its implementation; (3) Rectifying the impact by repairing, rehabilitating, or restoring the affected wetland environment; 1 (4) Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the activity; and (5) Compensating for the impact by replacing or providing substitute wetland resources or environments. A wetland alteration permit shall not be issued unless the proposed development complies within the provisions of the Mitigation Section of this ordinance, as well as the standards, intent, and purpose of this Article. If the City determines that the required calculations_ in a particular instance are needlessly burdensome because of the area and nature of a proposal, it may 1 agree to a substitute analysis. Sec. 20 -408. PERMIT REQUIRED. ' Drainage, grading, filling, burning, removal of healthy native vegetation, or otherwise altering or destroying a wetland of any size or type 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. (4) Creation of sedimentation and water quality improvement basins if part of a mitigation project, or used to restore or improve the function and value of the wetland. These basins may not be created in "pristine" wetlands and may only be created in "natural" wetlands 263 6 r11/17/92 1 1 if the City determines that there is no reasonable alternative. (5) Discharge of storm water runoff in a manner that impacts the wetland. Sec. 20 -409. FILLING. 1 When a wetland alteration permit is issued allowing filling in a wetland, the following standards shall be followed: (1) Filling must be consistent with the Chanhassen Surface Water Management Plan. 1 (2) Filling shall not cause total natural nutrient stripping capacity of the wetland to be diminished to an extent that is detrimental to any area river, lake, or stream. (3) Only fill free of chemical pollutants and organic 1 wastes may be used. (4) Filling shall be carried out so as to minimize the ' impact on vegetation. (5) Filling in wetland areas will not be permitted during waterfowl breading season or fish spawning season, unless it is determined by the City that the wetland is not used for waterfowl breeding or fish spawning. (6) Filling in wetland areas will be required to be mitigated in accordance with the requirements of this Article. Sec. 20 -410. DREDGING /EXCAVATION /GRADING. When a wetland alteration permit is issued allowing 1 dredging, excavating, or grading in a wetland, the following standards shall be followed: (1) The dredging will not have a net adverse effect on the ' ecological and hydrological characteristics of the 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 dredged area shall be limited to the minimum required for the proposed action. (5) Disposal of the dredged material is prohibited within the wetland area. 263 7 r11/17/92 , 1 Disposal of any dredged material shall include proper ( ) P Y er g P P erosion control and nutrient retention measures. ' (7) Dredging in any wetland area is prohibited during waterfowl breeding season or fish spawning season, 11 unless it is determined by the City that the wetland is not used for waterfowl breeding or fish spawning. (8) Dredging in wetland areas will be required to be mitigated in accordance with the requirements of this Article if the activity results in a loss of functional wetland. Dredging to create water quality improvement 11 basins may be allowed by the City where reasonable alternatives are not available or where the wetland is of low quality and designated for this purpose by the ' Chanhassen Surface Water Management Plan. Sec. 20 -411. STORM WATER RUNOFF. When a wetland alteration permit is issued allowing storm water runoff to discharge directly into a wetland, the following standards shall be followed: (1) An increase over the natural volume of storm water runoff from a development may be allowed when necessary for use of property, but only when it will not have a net adverse effect upon the ecological and hydrological characteristics of the existing wetlands. The restrictions on runoff set out below shall not be exceeded. Since the total increase in runoff which can be permitted is limited, the City, when considering permit applications, shall consider, in addition to the following, apportionment of increased runoff opportunity to all wetland property within the surrounding wetland area. (2) Storm water runoff from a development may be directed to the wetland only when free of debris and substantially free of chemical pollutants and silt, and only at rates which do not disturb vegetation habitat or increase turbidity. Sheet flow and other overland drainage of runoff shall be encouraged. (3) The allowed total increased runoff, in combination with the total fill allowed, shall not cause total natural flood storage or nutrient stripping capacity of the wetland to be reduced in a manner inconsistent with requirements established by the Chanhassen Surface Water Management Plan. Sec. 20 -412. MITIGATION. (a) Mitigation Intent. Where wetland alteration is ' approved and mitigation is required, mitigation must result in an improvement to the wetland function and 263 8 r11/17/92 1 value. Mitigation plans must address water quality, 11 improvement, and maintenance of pre - existing 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 state law to achieve replacement of the wetland function and value. Mitigation will not always be based solely on an acre to acre replacement, but may be based on replacement of habitat units (HU) through the use of habitat evaluation procedures. When significant improvements in the wetland value and function result, acre for acre surface area replacement may not be required. (b) Mitigation Standards. Mitigation of wetlands for function and value should be restored, created, and enhanced to have the following characteristics: (1) Relatively stable water levels subject to natural , fluctuations. (2) Pretreatment of inflow waters to improve quality. (3) High level of upland /lowland intermingling. (4) A ratio of open water to aquatic vegetation between 1:2 and 1:2. (5) High degree of intermingling of open water and aquatic vegetation. (6) High level of plant species diversity. (7) Restoration of native plant species in upland and lowland areas. (8) Undisturbed upland /lowland edge (i.e., buffer). (9) Meandered wetland edge. (10) Irregular bottom contours - mix of shallow and deep water. (11) Shallow side and bottom slopes - preferable 10:1 to 30:1 around and within wetland; steeper slopes may be used to provide open water and greater vegetation variability. (c) Mitigation Techniques. (1) Mitigation will be performed at a ratio required by state law. 263 9 r11/17/92 ' 1 (2) The City will use the Habitat Evaluation Procedures (HEP) to determine Habitat Units (HUs) ' to be replaced. (3) Mitigation should always result in an improvement to the wetland function and value. The wetland function and value will include improvement of water quality, maintaining hydrological balance, and provision of wildlife habitat. (4) Mitigation will not always be based solely on an acre to acre replacement, but may be based on ' replacement of habitat units (HU) through the use of habitat elevation procedures (appendix) at a ratio of 2:1. When significant improvements in the wetland value result, direct surface area replacement on a 2:1 basis may not be required. The City Council will determine when wetland impact will be allowed and the nature of mitigation which will be acceptable. (5) Mitigation shall provide a buffer strip as set forth in this Article. (6) Mitigation shall maintain or enhance the wetland hydrological balance through the following: - Restoration of deteriorated wetlands - Flooding of previously drained wetland basins - Creation of new wetlands - Enhancement of existing wetlands (7) Mitigation shall provide for pretreatment of water prior to it entering the wetland to improve water quality it required by the Chanhassen Surface Water Management Plan. (8) Mitigation, through the buffer strip, shall provide landscaping for nesting and food for wildlife habitat. The buffer strip landscape 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. (9) Wetland mitigation should be undertaken on -site. If this is not feasible, mitigation should occur locally within the sub- watershed. If this is not possible, mitigation should occur outside the sub- watershed, elsewhere in the City. If mitigation cannot be accomplished on site, or if the City deems it necessary to perform mitigation off -site, the applicant shall be responsible for contributing into the City's wetland mitigation 263 10 r11/17/92 1 fund. The performed mitigation erformed off -site shall meet g the above requirements. (10) The City may determine that the public interest is best served by requiring off -site wetland mitigation. This determination will be made based upon the City of Chanhassen's Surface Water Management Plan. When this situation arises or when the applicant is unable to restore wetlands on -site, the City will require payment into the dedicated Wetland Mitigation Banking Fund. This fund shall be used solely to create new and /or expand and improve existing wetlands according to the priorities outlined in this Article. The City Council shall establish the fee structure on an annual basis. Fees shall be based upon the average price for similar property elsewhere in the City. (d) Construction Management and Long Term Wetland Maintenance. 1 (1) The permit holder shall follow the City's best management practices to minimize direct impacts due to erosion and construction practices and to safeguard wildlife habitat. (2) The permit holder shall conduct a monitoring 1 program and evaluation until construction is completed. A letter of credit from the permit holder shall be held to ensure compliance similar to any other public improvement. The City will ensure that the permit holder is delivering the wetland that was promised. The permit holder shall demonstrate compliance with the designed wetland as -built plans. Where feasible, the City shall require the permit holder to satisfy long term management requirements. Sec. 20 -413. APPLICATION AND ISSUANCE OF PERMIT. 1 The applicant for a wetland alteration permit shall furnish the information required by the City including, but not limited to, a site plan, topographic data, hydrological data, and habitat evaluation procedures for the review of a wetland alteration permit application. The Planning Director shall use discretion regarding the level and complexity of information required to review the request. 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. The applicant shall have the burden of proving that the proposed use or activity complies with the purposes, intent, and other provisions of this Article. The Council may establish reasonable conditions which are specifically set forth in the permit to 263 11 r11/17/92 ' 1 ensure 4u compliance with requirements contained in this Article. P 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 function and value, establish required monitoring procedures and maintenance activity, stage the work over time, require the alteration of the site design to ensure buffering, require the provision of a performance security. Sec. 20 -414. INSPECTION OF WORM. 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 -415. EXPIRATION AND RENEWAL OF PERMIT. (a) Unless otherwise specified by the City Council, the person issued a wetland alteration permit shall begin and complete the development authorized by the permit within one (1) year after the date the Council approves the permit application. ' (b) The permittee shall provide written notice to the City twenty -four (24) hours prior to the commencement and completion ' of the development project. No project shall be deemed to have been completed until approved by the City after receipt of notice of completion. 11 (c) If the permittee fails to commence work on the development within the time specified in this section, the permit shall be void. The Council may renew a void permit at its 11 discretion. If the Council does not renew the permit, the holder of the void permit may make original application for a new permit. (d) The permittee may make written application to the 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. Sec. 20 -416. EXEMPTIONS. Activities exempted by Minnesota Statutes 103G.2241 from ' State Wetlands Protection shall be exempted from the provisions of this Article. However, certificates of exemption must be obtained from the City and filed with the County Recorder prior to starting work. The statutory exemptions include, but are not limited to: (1) Activities necessary to repair and maintain existing public or private drainage systems as long as wetlands 263 12 r11/17/92 1 1 that have been in existence for more than twenty (20) years are not drained. (2) Activities authorized under, and conducted in accordance with, an applicable general permit issued by the United States Army Corps of Engineers under Section 404 of the Federal Clean Water Act, United States Code, Title 33, Section 1344, except that nationwide permit in Code of Federal Regulations, Title 33, Section 330.5, paragraph (a), clause (14), limited to when a new road crosses a wetland, and all of clause (26). (3) Placement, maintenance, repair, enhancement, or replacement of utility or utility -type service, including the transmission, distribution, or furnishing, at wholesale or retail, of natural or manufactured gas, electricity, telephone, or radio service or communications if: - the impacts of the proposed project on the 1 hydrologic and biological characteristics of the wetland have been avoided and minimized to the extent possible; and 1 - the proposed project significantly modifies or alters less than one -half acre of wetland. (4) Activities associated with routine maintenance of utility and pipeline rights -of -way, provided the activities do not result in additional intrusion into the wetland. (5) Alteration of a wetland associated with the operation, maintenance, or repair of an interstate pipeline. �. (6) Activities associated with routine maintenance of existing public highways, roads, streets, and bridges, 1 provided the activities do not result in additional intrusion into the wetland and do not result in the draining or filling, wholly or partially, of a wetland. 1 (7) Emergency repair and normal maintenance and repair of existing public works, provided the activity does not result in additional intrusion of the public works into the wetland and do not result in the draining or filling, wholly or partially, of a wetland. (8) Normal maintenance and minor repair of structures causing no additional intrusion of an existing structure into the wetland, and maintenance and repair of private crossings that do not result in the draining or filling, wholly or partially, of a wetland. (9) Development projects and ditch improvement projects in the state that have received preliminary or final plat 263 13 r11/17/92 1 approval, or infrastructure that has been installed, or having local site plan approval, conditional use ' permits, or similar official approval by the City or other approving governmental body or agency after August 1, 1987. Bec. 20 -417. VARIANCES. Variances from the requirements of this Article may be granted in accordance with the variance provisions of this Chapter as regulated by Article II, Division III of this Code. Bec. 20 -418. ENFORCEMENT PROCEDURES. (a) Violation of Article VI, Wetland Protection, or of the terms of a permit issued thereunder shall be a misdemeanor punishable by ninety (90) days in jail and a seven hundred dollar ($700.00) fine. ' (b) Any person who alters a wetland in violation of Article VI, 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. (c) Wetland reviews conducted by the City shall be coordinated with State of Minnesota Wetland Protection Statutes and rules. (d) Notice of requested wetland alteration permits shall be 1 mailed to all property owners located within 500 feet of the requested activity. Notification requirements established by State of Minnesota Wetland Protection Statutes and official rules shall be coordinated with City approvals. Section 2. Section 20 -1 of the Chanhassen City Code is amended by deleting the following definitions: Class A Wetlands means wetland types 3, 4, 5, 6, 7, and 8. In case of wetlands adjoining a public waters designated as lake or pond this class shall also include type 2 wetlands. Type 2 wetlands shall also be deemed a Class A wetland when 11 adjoining a stream designated as public waters to the extent that it encroaches upon the 100 -year floodplain of the stream. ' Class B Wetlands means type 2 wetlands not adjoining a public waters designated as lake or pond nor within the 100 -year floodplain of a stream designed as public waters. Wetland Types means classifications of wetlands as defined in U.S. Department of Interior, Fish and Wildlife Service, Circular 39, "Wetlands of the U.S. 1956 ". 263 14 r11/17/92 1 Wetland Watershed means that area of land from which water drains into a Class A or Class B wetland. Section 3. Section 20 -1 of the Chanhassen City Code is amended by adding the following definitions: Buffer Strip means an area of nondisturbed ground cover abutting a wetland left undisturbed to filter sediment, materials, and chemicals. Habitat Evaluation Procedures (HEP) is a species- habitat data management system for impact assessment developed by the U.S. Fish and Wildlife Service. Its purpose is to document predicted impacts to fish and wildlife from proposed land and water resource development projects. Habitat quality for selected key species is described by an index, the Habitat Suitability Index (HSI). Habitat Suitability Index (HSI) is a fish or wildlife species- specific index value rating the ability of key habitat components to supply essential life requirements for the species. Index value ranges between 0 to 1.0. Habitat Units (HU). Habitat Suitability Index (HSI) multiplied by the area of habitat being evaluated. HU's are used for comparing habitat quality from one wetland to the next or for measuring the effectiveness of mitigation. HU's integrate both quality and quantity of habitat. Principal Structure. The main building as distinguished ' from an accessory building or structure. Vegetation, Native. Native vegetation is the pre - settlement 1 group of plant species native to the North American continent which were not introduced as a result of European settlement. ' Wetlands means lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water. For purposes of this definition, wetlands must have the following three attributes: (1) have a predominance of hydric soils; (2) are inundated or saturated by surface or ground water at a frequency and duration sufficient to support a prevalence of hydrophytic vegetation typically adapted for life in saturated soil conditions; and (3) under normal circumstances support a prevalence of such vegetation. 263 15 r11/17/92 1 1 4 wetlands does not include types 3, 4, and 5 wetlands, ( ) yP � � as defined in United States Fish and Wildlife Service 1 Circular No. 39 (1971 edition), not included within the definition of public waters, that are 2 -1/2 or more acres in size. 1 Utilized. Utilized water bodies created for the specific purpose of surface water runoff retention and /or water ' quality improvements. These water bodies are not to be classified as wetlands even if they take on wetland characteristics. Wetland alteration permits shall not be required to undertake work on these water bodies. Wetlands, Acs /Urban. Wetlands that have been influenced by agricultural or urban (residential, commercial, or industrial) land usage are called Ag /Urban. Influences include: over nutrification, soil erosion and sedimentation, and water quality degradation. As 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. Wetlands. Natural. Natural wetlands are still in their natural state and typically show little sign of impact from surrounding land usage. The vegetative community of these wetlands are 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. Wetlands, Pristine. Wetlands that exist in a natural state and have special and unusual qualities worth protecting at a high level are called Pristine. These qualities include: outstanding vegetation community, native species population, rare or unusual species present, and habitat for rare wildlife species. 1 Section 4. This ordinance shall be effective immediately upon its passage and publication. PASSED AND ADOPTED by the Chanhassen City Council this day of , 1992. 1 ATTEST: Don Ashworth, Clerk /Manager Donald J. Chmiel, Mayor (Published in the Chanhassen Villager on , 1992.) 263 16 r11/17/92