1050.010: - WETLAND OVERLAY DISTRICT

Subd. 1. Findings, Intent and Incorporation by Reference.

• A. The City has determined that wetlands serve to maintain water quality by filtering water that is discharged into ground water aquifers and by retaining inorganic sediments, toxicants and nutrients. They also retain and reduce the discharge of phosphorus and transform nutrients from their inorganic to organic forms, thereby protecting streams and water bodies from eutrophication and contamination. Wetlands also store runoff and reduce the velocity and magnitude of flood peaks.

• B. Wetland vegetation also prevents the erosion of shoreline areas. Wetland vegetation provides food, shelter, and important habitat for wildlife. All of these wetland characteristics provide valuable recreation and education resources.

• C. The City has also found that wetlands vary significantly in the degree that they have been altered. Wetlands within the City exhibit great variations in their floral diversity, quality of wildlife and fishery habitat, degree of fluctuation in response to storms, the extent to which their shorelines have been altered or eroded, and their relative value in protecting water quality. Therefore, the City has found it necessary and beneficial to classify wetlands based upon their functions and values. The City has also found that it is in the best interest of the general health and welfare of the City to achieve no net loss of wetlands within the community.

• D. The City recognizes that a substantial amount of wetland degradation results from sedimentation and nutrient loading related to construction projects. Therefore, the City finds it necessary to require extraordinary measures to prevent such construction related degradation.

• E. In addition to having regulations that affect the physical impacts within wetland areas the City also finds that it is necessary to regulate the use of lands surrounding wetlands. Buffer strips are necessary and beneficial to maintaining the health of wetlands. These strips of land

surrounding wetlands protect their shorelines from erosion, while serving to filter sediment, chemicals and other nutrients before the storm water discharges into the wetland. Buffer strips are also beneficial in providing habitat for wildlife.

• F. This Section hereby incorporates by reference the Wetlands Conservation Act of 1991 [Minn. Stat. 103G.221 et seq. (hereinafter referred to as the WCA)] and any future amendments adopted by the legislature. All wetlands, as defined in Section 1020.020 of this Chapter, including those governed by the Department of Natural Resources, are covered by the other provisions of this Chapter. Also, there are circumstances under which the strict enforcement of these regulations may be unreasonable and in circumstances that meet the criteria established in Subd. 5 of this Chapter, departures from the strict application of these standards may be permitted.

• G. It is the intent of this Chapter to avoid the alteration and destruction of wetlands. When wetlands are altered or destroyed, the mitigation must be provided to recreate the functions and values of the wetland.

Subd. 2. Purpose and Implementation.

• A. Through the adoption and enforcement of this Section, the City shall promote the general health, safety, and welfare of its residents by both conserving and protecting wetlands and requiring sound management practices and mitigation as provided for in the WCA when development occurs in the vicinity of wetlands. Through the implementation of this Section, the City seeks to accomplish the following purposes:

  1. To satisfy the requirements of the WCA as it may be amended and, thereby achieve no net loss of wetlands within the City;

  2. To balance the needs to preserve and protect natural resources and systems with both the rights of private property owners and the need to support the efficient use of developable land within the City;

  3. To preserve the natural character of the landscape through the maintenance of wetland ecosystems;

  4. To promote water quality by maintaining the ability of wetlands to recharge ground water and receive the discharge of ground water, to retain sediment and toxicants and filter nutrients from surface water runoff before it discharges into community lakes and streams, thus avoiding the contamination and eutrophication of these water features; and

  5. To provide wildlife habitat and thereby support the maintenance of diversity of both plant and animal species within the City.

• B. To accomplish these purposes, the City:

  1. Has conducted an inventory of wetlands and other natural areas within the City;

2. Has developed a system of classification for wetlands within the City and classified the City's wetlands based upon their relative values related to floral diversity, wildlife habitat, water quality protection, fishery habitat, flood storage, shoreline protection, and aesthetic, recreational and educational benefits using the Minnesota Rapid Assessment (MNRAM) methodology;

3. Has prepared and maintains a comprehensive set of official maps identifying the location and classification of wetlands inventoried in the Natural Resources Inventory;

4. Has established wetland regulations that are coordinated with flood plain and shoreland protection regulations;

5. Requires sound management practices to protect, conserve, maintain, enhance, and improve the quality of wetlands within the community;

6. Enforces standards for the alteration of wetlands when alteration is allowed, including standards and procedures for the mitigation of the loss of wetland areas and their functions and values, when alteration or destruction occurs;

7. Obtains protective easements over or acquires fee title to wetlands as appropriate;

8. Educates the public about the numerous benefits and features that wetland provide and the adverse effects of improperly managed development on wetlands.

Subd. 3. General Provisions.

• A. Identification and Delineation of Wetlands

1. This Section shall apply to all land containing wetlands and land within the setback and buffer areas required by this Section. Wetlands shall be subject to the requirements established herein, as well as restrictions and requirements established by other applicable Federal, State, and City ordinances and regulations. These wetland protection regulations shall not be construed to allow anything otherwise prohibited in the zoning district where the wetland is located.

   2. A wetland is land that meets the definition of "wetlands" set forth in Section 1020.020. The classification of a wetland shown on the "Natural Resource Communities Quality Ranking Map" will be prima facie evidence of the classification of a wetland.

   3. The presence or absence of a wetland on the official maps does not represent a definitive determination as to whether a wetland covered by this Section is or is not present. Wetlands that are identified during site specific delineation activities but do not appear on the official wetland maps are still subject to the provisions of the Section. Areas that appear on the official wetland maps as wetlands that are not identified as wetlands during site specific delineation activities are not subject to the provisions of this Section.

It will be the responsibility of an applicant for required City approvals or permits to delineate the exact wetland boundary or to determine that no wetland exists on a subject property. All delineations must be reviewed and approved by the City or its delegated authority.

5. If an applicant questions whether a wetland exists or disputes its classification on the official map, the applicant shall have the burden to supply detailed information for review supporting the applicant's assertion, including but not limited to, topographic, hydrologic, floristic, and/or soil data deemed necessary by the City to determine the jurisdictional status of the wetland, its exact boundary and its classification. Wetland delineations supplied by applicants shall be certified by a qualified wetland delineator. Wetland delineators must satisfy any certification requirements that may be established by the U.S. Army Corps of Engineers or the Minnesota Board of Water and Soil Resources.

6. Applicants seeking a change in wetland classification must submit to the City a completed MNRAM version 1.0 form, or the most recent version. The technical evaluation panel will review the request for change. The technical evaluation panel will make a recommendation to the City regarding a change in classification.

7. Only that portion of a property within the boundaries of a wetland shall be subject to the provisions of this Section.

8. This Section establishes three wetland classifications as defined in Section 1020.020: High Quality, Medium Quality, and Low Quality.

Subd. 4. General Standards.

The following standards apply to all lands within and/or abutting a wetland:

• A. Septic and soil absorptions systems must be setback a minimum of 75 feet from the City approved boundary of the wetland.

• B. The lowest ground floor elevation shall be 2 feet above the 100-year flood elevation or three feet above the Ordinary High Water Mark of public waters regulated by Section 1050.020, whichever is greater.

• C. Structures intended to provide access across a wetland shall be prohibited unless a permit is obtained in conformance with State Regulations.

• D. The MPCA's Best Management Practices shall be followed to avoid erosion and sedimentation during the construction process.

• E. City inspection schedules and fines for erosion control will double on projects abutting wetlands.

• F. Before the City issues a building permit for a lot with a required wetland buffer, the lot owner shall:

Record a notice of the wetland buffer requirement against the title to the lot with the office of the Hennepin County Recorder or Registrar of Titles, and

2. Install the wetland monuments required by Subd. 7 of this Chapter.

Subd. 5. Wetland Buffer Strips and Setbacks.

• A. For lots of record created after March 23, 2004, a buffer strip shall be maintained abutting all wetlands identified in Subd. 3 below. The setback and buffer provisions of this Chapter shall not apply to lots of record on March 23, 2004, to developments for which conditional use permits, site plans, and preliminary plats, final plats or preliminary or final planned unit development plans have been approved by the City within 2 years prior to March 23, 2004, or to developments for which complete applications for any of the above actions have been accepted by the City for review, but not yet acted upon, prior to March 23, 2004. The City does, however, strongly encourage the use of a wetland buffer and setback on all lots in the City.

• B. Wetland buffer strips and structure setbacks shall apply to all parcels of land whether or not the wetland is on the same parcel as a proposed development.

• C. Wetland buffer strips are required on wetland sizes and types as follows:

Wetland Buffers and Setback Requirements

*Buffer widths in excess of the listed maximums shall not be used in calculating average buffer width.

**These setbacks shall take precedence over other setbacks required in this Chapter. These

setbacks apply to structures only—a 5-foot setback is required for roads and parking lots. Trails

that serve an interpretive function may be exempted from buffer and setback requirements.

Example of Buffer and Setback

Applied to a High Quality Wetland

==> picture [288 x 197] intentionally omitted <==

• D. Notwithstanding the foregoing, wetland buffer strips are not required for:

  1. A wetland if Minnesota Statutes Section 103G.2241, subdivision 4, 5 or 9 would exempt the draining or filling of that wetland from the replacement plan requirements of Minnesota Statutes Section 103G.222, or

2. A wetland that is a Type 1, 2 or 6 wetland as defined in Minnesota Statutes Section 103G.005, subdivision 17b and that is located outside the Natural Resources Corridors identified on official City maps.

• E. Buffer strip vegetation shall be established and maintained in accordance with the requirements found in this Subdivision. During the first 2 years, any buffer vegetation that does not survive must be replanted. After 2 years, if the condition of the buffer area changes through natural processes not caused by the property owner, the owner shall not be required to reestablish the buffer area to meet the standards contained in Subd. 8 of this Chapter. Buffer strips shall be identified within each lot by permanent monuments approved by the City.

• F. For roadways that must be aligned either adjacent to or across wetlands and are subject to WCA replacement requirements, additional wetland filling to create a buffer strip shall not be required. Trails that the City has determined serve an interpretive function may also be exempted from the buffer requirement. All other roadways and trails shall meet the buffer standards established in this Subd. or in Subd. 6 below.

• G.

If the area of the buffer has a preconstruction slope of 12 percent or greater, the buffer shall be at the applicable maximum for width for the wetland classification. The use of a meandering buffer stripe to maintain a natural appearance is encouraged but not required in areas of flat topography.

• H. The required structure setback shall apply to all structures, except that such structure setback shall be reduced to 5 feet for roadways, trails, and parking lots, and their related retaining walls and fences.

• I. Wetland buffer strips not required by this Section may be voluntarily created in conformance with the requirements of this Section concurrent with approval of a site plan, or in the absence of a site plan, upon approval of an administrative permit.

Subd. 6. Alternative Wetland Buffer Strips and Setbacks: With Extraordinary Management Measures.

• A. Because of the unique physical characteristics of a specific parcel of land, narrower buffer strips may be necessary to allow for a reasonable use of land,

• B. The City Council may approve alternative standards, based on an assessment of the following:

  1. Size of the parcel

  2. Existing roads and utilities

  3. Percentage of parcel impacted by wetlands

  4. Configuration of wetlands on the parcel

  5. Quality of the affected wetlands

• C. The City Council will evaluate the appropriateness of using the alternative standards as a part of its review of a sketch plan. An applicant must receive Council approval through this review process prior to submitting a preliminary plan or plat application that applies the alternative buffer strip standards.

• D. Alternative standards shall not be allowed on wetlands within the Natural Resource Corridors identified on official City maps.

• E. In instances where the City Council approves alternative buffer standards, an applicant will be required to apply extraordinary management measures to control erosion, sedimentation and nutrient loading during and for two years after construction. The applicant must demonstrate that the proposed measures will limit dissolved phosphorus concentration to one milligram per liter (mg/l) or less. Buffer strips and structure setbacks shall meet the following standards:

Alternative Wetland Buffers and Setbacks, with Extraordinary Measures

*Buffer widths in excess of the listed maximums shall not be used in calculating the average buffer width.

**These setbacks shall take precedence over other setbacks required in this Chapter. Structure

setbacks apply to structures only; roads, trails and parking lots shall have a 5-foot required setback.

• F. Extraordinary management measures that may be permitted in conjunction with and up-slope from the buffer strip and setback requirements listed above include, but are not limited to measures that add redundant protections to normal required Best Management Practices.

• G. The applicant shall be responsible to submit all of the necessary information to document that the proposed extraordinary construction and stormwater management practices (hereinafter referred to as "Extraordinary Management Practices") will at least duplicate the performance of the required buffers and setbacks shown in Subd. 5 of this Chapter, if not exceed it. The applicant shall also have the burden of proving that the purpose and objectives of the Chapter will be met through the use of these Extraordinary Management Practices.

• H. The approval of any Extraordinary Management Practices shall be conditioned upon a site improvement performance agreement (Section 1070.050, Subd. 9 of this Chapter) that includes a binding commitment to the maintenance of the proposed alternative treatments throughout their useful life.

Subd. 7. Monument Required.

A permanent wetland buffer monument shall be installed at each lot line where it crosses a wetland buffer, and where needed to indicate the contour of the buffer, with a maximum spacing of 200 feet of wetland edge. If no buffer is required, the monument shall be at the edge of the wetland.

Subd. 8. Buffer Strip Vegetation Performance Standards.

A.

Where acceptable natural vegetation exists in buffer strip areas, the retention of such vegetation in an undisturbed state is preferred. A buffer strip has acceptable natural vegetation if it:

1. Has a continuous, dense layer of perennial grasses that have been uncultivated or unbroken for at least 10 consecutive years, or

2. Has an overstory of trees and/or shrubs with at least 80 percent canopy closure that have been uncultivated or unbroken for at least 10 consecutive years, or

3. Contains a mixture of the plant communities described in (1) and (2) above, that have been uncultivated or unbroken for at least 10 consecutive years.

• B. Notwithstanding the above performance standards, the City may determine existing buffer vegetation to be unacceptable if:

  1. It is composed of undesirable plant species (including, but not limited to reed canary grass, common buckthorn, purple loosestrife, leafy spurge and noxious weeds), or

  2. It is lacking a layer of organic thatch or duff, or

  3. Has topography that tends to channelize the flow of surface runoff, or

  4. For some other reason it is unlikely to retain nutrients and sediment.

• C. Where buffer areas, or a portion thereof, are not vegetated or have been cultivated or otherwise disturbed within 10 years of the permit application, such areas shall be re-planted and maintained according to each of the following standards:

  1. The soil in wetland buffer strips shall be amended, as necessary, to ensure that the soil has an organic content of not less than 10 percent and not more than 20 percent.

  2. Buffer zones shall be planted with a seed mix containing 100 percent perennial native plant species, except for a one-time planting of an annual nurse or cover crop such as oats or rye.

  3. The seed mix to be used shall consist of at least 12 pounds pure live seed (PLS) per acre of native prairie grass seed and 5 pounds PLS per acre of native forbs. Native prairie grass and native forb mixes shall contain no fewer than 4 and 5 species respectively.

  4. The annual nurse or cover crop shall be applied at a rate of 20 pounds per acre.

  5. Native shrubs may be substituted for forbs. Such shrubs may be bare root seedlings and shall be planted at a rate of 60 plants per acre. Shrubs shall be distributed so as to provide a natural appearance and shall not be planted in rows.

  6. Any ground cover or shrub plantings installed in buffer areas are independent of landscaping requirements set forth elsewhere in the City Code and City policy.

  7. Native prairie grasses and forbs shall be planted by a qualified contractor using a drill designed for native prairie grass seedlings, such as a Truax or Nesbitt Native Grass Drill or a John Deere 1550 Power-Till Seeder.

  8. No fertilizer shall be used in establishing new buffer zones, except on highly disturbed sites when deemed necessary to establish acceptable buffer vegetation and then limited to amounts indicated by an accredited soil testing laboratory.

  9. All seeded areas shall be mulched immediately with clean straw at a rate of 1.5 tons per acre. Mulch shall be anchored with a disk or tackifier. On slopes that are steeper than 3:1, additional soil stabilization materials such as straw mat or coconut fiber mat shall be used, as specified in the MnDOT Seeding Manual 2000, or most recent MnDOT manual.

  10. Buffer zones (both natural and created) shall be protected by silt fence during construction and the fence shall remain in place until the area crop is established.

11. Applicants may obtain from the City a set of standard seeding and planting specifications for buffer zones that meet all City requirements.

• D. During the first 2 years, the developer shall replant any buffer vegetation that does not survive. After 2 years, if the condition of the buffer area changes through natural processes not caused by the property owner, the owner shall not be required to reestablish the buffer area to meet the standards established in this subdivision.

Subd. 9. Encroachment in Required Setback and Buffer Areas.

• A. Patios and decks may encroach up to a maximum of 6 feet into required structure setback areas. Porches may not encroach into required setback areas. Buffer and wetland areas must be kept fee of all structures, including fences and play equipment.

• B. Water quality ponds may encroach into required wetland buffer areas, provided that the amount of buffer encroached upon does not exceed 50 percent of the total area required for such ponding, and provided that the amount of buffer encroached upon does not exceed 50 percent of the total area required for buffering. These limitations may be exceeded where two-cell water quality ponding is utilized.

Subd. 10. Variances.

• A. Requests for variances shall be made in accordance with the procedures and requirements set forth in Section 1070.040 of this Chapter.

• B. Variances shall only be granted when the standards and criteria set forth in Section 1070.040 of this Chapter have been met. Variances shall not be granted which would circumvent the intent and purposes of this subdivision.