Land development projects and associated increases in impervious cover alter the hydrologic response of local watersheds and increase stormwater runoff rates and volumes, flooding, erosion, and sediment transport and deposition, and water-borne pollutants. The purpose of this ordinance is to protect and safeguard the general health, safety, and welfare of the public by regulating stormwater runoff and to protect local water resources from degradation.

Subd. 1.

For the purposes of this section, the following terms shall mean:

Subd. 2.

Accelerated erosion: Erosion caused by development activities that exceed the natural processes by which the surface of the land is worn away by the action of water, wind, or chemical action.

Subd. 3.

Applicant: A property owner or agent of a property owner who has filed an application for a permit.

Subd. 4.

Building: Any structure, either temporary or permanent, having walls and a roof, designed for the shelter of any person, animal, or property, and occupying more than 100 square feet of area.

Subd. 5.

Channel: A natural or artificial watercourse with a definite bed and banks that conducts continuously or periodically flowing water.

Subd. 6.

Dedication: The deliberate appropriation of property by its owner for general public use.

Subd. 7.

Developer: A person who undertakes land disturbance activities.

Subd. 8.

Drainage easement: A legal right granted by a landowner to a grantee allowing the use of private land for stormwater management purposes.

Subd. 9.

Fee-in-lieu: A payment of money in place of meeting all or part of the stormwater performance standards required by this ordinance.

Subd. 10.

Grading, drainage, and erosion control plan: A set of plans prepared by or under the direction of a licensed professional engineer that depicts existing and proposed grading, temporary and permanent drainage facilities, and indicates the specific measures and sequencing to be used to control sediment and erosion on a development site before, during and after construction.

Subd. 11.

Impervious cover: Those surfaces that cannot effectively infiltrate rainfall (e.g., building rooftops, pavement, sidewalks, driveways, etc.).

Subd. 12.

Land disturbing activity: Any activity, which changes the volume or peak flow discharge rate of rainfall runoff from the land surface. This may include the grading, digging, cutting, scraping, or excavating of soil, placement of fill materials, paving, construction, substantial removal of vegetation, or any activity, which bares soil or rock or involves the diversion or piping of any natural or man-made watercourse.

Subd. 13.

Nonpoint source pollution: Pollution from any source other than from any discernible, confined, and discrete conveyances, and shall include, but not be limited to, pollutants from agricultural, silvicultural, mining, construction, subsurface disposal and urban runoff sources.

Subd. 14.

National Pollutant Discharge Elimination System (NPDES) Storm Water Discharge Permit: A permit issued by EPA (or by a State under authority delegated pursuant to 33 USC 1342(b)) that authorizes the discharge of pollutants to waters of the United States, whether the permit is applicable on an individual, group, or general area-wide basis.

Subd. 15.

On-site management: A stormwater management measure located within the subject property boundary described in the permit application for land development activity.

Subd. 16.

Recharge: The replenishment of underground water reserves.

Subd. 17.

Site development permit: The permit issued by the municipality for which the purpose is construction or alteration of ground.

Subd. 18.

Stop-work order: An order issued which requires that all construction activity on a site be stopped.

Subd. 19.

Stormwater management: The use of structural or non-structural practices that are designed to reduce stormwater runoff pollutant loads, discharge volumes, peak flow discharge rates and detrimental changes in stream temperature that affect water quality and habitat.

Subd. 20.

Stormwater management plan: The hydrologic analysis report and drainage area map(s) that provides the pre-development and post-development hydrologic site conditions.

Subd. 21.

Stormwater runoff: Flow on the surface of the ground, resulting from precipitation.

Subd. 22.

Wetland: An area that is inundated or saturated by surface water or groundwater at a frequency and duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions, commonly known as hydrophytic vegetation.

Subd. 1.

This section shall be applicable to all subdivision, site plan, building permit or grading permit, unless eligible for an exemption or granted a waiver by the city. No building permit, subdivision approval, or permit to allow land disturbing activities shall be issued until approval of the stormwater management plan, or a waiver of the approval requirements, has been obtained with the provisions of this ordinance.

Subd. 2.

Exemptions. The provisions of this ordinance do not apply to:

(a)

The plowing, tilling, planting, or harvesting of agricultural, horticultural, or silvicultural crops.

(b)

Additions or modifications to existing single-family structures.

(c)

Construction of single-family structures that disturbs less than one acre of land.

(d)

Site development of lots for which a stormwater management plan was approved as part of a larger common development plan.

(e)

Any emergency activity which is immediately necessary for the protection of life, property or natural resources.

Subd. 3.

Waivers. Every applicant shall provide for stormwater management as required by this ordinance, unless a written request is filed to waive this requirement. The city council, upon recommendation of the planning commission, may waive any requirement of this ordinance upon making a finding that compliance with the ordinance would cause an unnecessary hardship and the waiver of such requirement will not adversely affect the objectives of this ordinance. Requests to waive the stormwater management requirements shall be submitted to the city for approval.

Subd. 4.

In instances where meeting the minimum on-site management requirements is not feasible due to the natural or existing physical characteristics of a site, the city may grant a waiver from strict compliance with these stormwater management provisions, as long as acceptable mitigation measures are provided. However, to be eligible for a waiver, the applicant must demonstrate to the satisfaction of the city that the waiver will not result in the following impacts to downstream waterways:

(a)

Deterioration of existing culverts and other structures.

(b)

Increase in stormwater runoff rates and volume, soil erosion, siltation, stream temperature, or nonpoint source pollution.

(c)

Accelerated streambank or streambed erosion or siltation.

(d)

Increased threat of flood damage to public health, life, property.

Subd. 5

Where compliance with minimum requirements for on-site stormwater management is waived, the applicant will satisfy the minimum requirements by meeting one of the mitigation measures selected by the city. Mitigation measures may include, but are not limited to, the following:

(a)

The creation of a stormwater management facility or other drainage improvements on previously developed properties, public or private, that currently lack stormwater management facilities designed and constructed in accordance with the purposes and standards of this ordinance.

(b)

Monetary contributions (fee-in-lieu) to fund stormwater management activities that are designed to service multiple land disturbing and development activities undertaken by one or more persons, including the applicant.

1.

Where the city waives all or part of the minimum stormwater management requirements, or where the waiver is based on the provision of adequate stormwater facilities provided downstream of the proposed development, the applicant shall be required to pay a fee in an amount as determined by the city.

2.

When an applicant obtains a waiver of the required stormwater management, the monetary contribution required shall be in accordance with the adopted fee schedule. All of the monetary contributions shall be credited to an appropriate capital improvements program project, and shall be made by the developer prior to the issuance of any building permit for the development.

(c)

Dedication of land. In lieu of a monetary contribution, an applicant may obtain a waiver of the required stormwater management by entering into an agreement with the city for the granting of an easement or the dedication of land by the applicant, to be used for the construction of an off-site stormwater management facility. The agreement shall be entered into by the applicant and the city prior to the recording of plats or, if no record plat is required, prior to the issuance of the building permit.

Subd. 1.

It is the policy of the city to require development and redevelopment to control stormwater quantity and quality through a management approach of detention, infiltration basins, or other approved BMPs. Detention and infiltration basins, whether on-site or regional in nature, shall be designed to incorporate all requirements of the Minnesota NPDES/SDS General Stormwater Permit for Construction Activity (MN R100001).

Subd. 2.

The storm water management plan shall be in conformance with the requirements of the approved local water management plan for the city, as amended.

Subd. 3.

Facilities shall be designed in accordance with the approved local water management plan and standard specifications for the city, as amended.

Subd. 4.

Rate control and water quality standards apply to all new development.

Subd. 5.

Volume control standards apply to new development where there are hydrologic soil group A and B soils. The volume of the first one inch of runoff from the new impervious area shall be infiltrated.

Subd. 6.

Phosphorous loading reduction. Facilities shall be designed to reduce phosphorous loading at down gradient site boundaries such that there is no net increase in pollutant loads as a result of development.

Subd. 1.

The city finds that wetlands serve a variety of beneficial functions and values. Wetlands maintain water quality, reduce flooding and erosion, provide food and habitat for wildlife, provide open space, and are an integral part of the city's environment. Wetlands are important physical, educational, ecological, aesthetic, recreational, and economic assets to the city. They are critical to the city's supply of clean drinking water, stormwater management, and other aspects of health, safety, and general welfare. Regulating wetlands and the land uses around them is therefor in the public interest.

Subd. 2.

In order to protect wetlands, this chapter incorporates by reference the Minnesota Wetland Conservation Act of 1991 (hereinafter referred to as the WCA) and any future amendments adopted by the legislature.

Subd. 3.

Wetland function and value assessment. The city has found that wetlands vary significantly in the degree that they have been altered. Wetlands exhibit great variations in their overall quality. Therefore, the city has determined that it is necessary and beneficial to protect wetlands based on the needs for their existing quality. A wetland function and value assessment shall be required in accordance with the provisions of the approved local water management plan for the city, as amended. Function and value assessments shall be required when any of the following activities are proposed:

(a)

Subdivision.

(b)

Any projects with wetland impacts as defined by the WCA (Minn. R. 8420).

(c)

Wetland excavation greater than 0.5 acres.

Subd. 4.

Wetland buffer strips. In addition to having regulations that affect the physical impacts within wetland areas, regulatory agencies require the city to address potential non-point source impacts from future development with the establishment of buffer strip standards to complement the existing stormwater standards. A buffer strip is an upland area left in, or restored to, its natural state (non-turf grass) that surrounds a wetland or stormwater pond and reduces negative impacts to wetlands from adjacent development. Buffer strips are necessary because:

(a)

Drainage swales, ditches, storm sewers and culverts typically collect street and front yard drainage and direct the drainage to an appropriately sized pond for pre-treatment prior to discharge to a wetland or water body. Back yard drainage typically reaches wetlands or water bodies without any pretreatment thereby allowing lawn and garden chemicals, sediments, pet wastes, fertilizer, and other types of contaminants to directly impact the receiving water body.

(b)

To promote water quality by maintaining the ability of wetlands to recharge groundwater and receive the discharge of groundwater, to retain sediment and toxins, and to filter nutrients from surface water runoff before it discharges into receiving waters, thus avoiding the contamination and eutrophication of these water features.

(c)

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

(d)

To preserve the natural character of the landscape through the restoration of wetland ecosystems.

Wetland buffers are unmowed areas adjacent to wetlands that contain non-invasive vegetation, preferably dense native vegetation. Buffers filter pollutants before they can enter the wetland, reduce erosion, protect vegetation diversity and wildlife habitat, and minimize human impacts to the wetlands. Buffers are required around all wetlands within new subdivisions, with the width dependent upon relative susceptibility.

1.

Design standards. Buffer strips shall be designed in accordance with the approved local water management plan and standard specifications for the city, as amended.

2.

Buffer monuments. Buffers shall be adequately marked with approved signage at maximum 200-foot spacing.

3.

Minimum buffer widths. Minimum widths are shown in Table 1 below.

Table 1. Wetland Management Standards

Subd. 1.

All stormwater management facilities shall be designed to minimize the need of maintenance, to provide access for maintenance purposes, and to be structurally sound. It shall be the responsibility of the applicant to obtain or provide any necessary easements or other property interests to allow for inspection and maintenance purposes.

During the application process, the city shall determine who the responsible party will be for the ownership and maintenance of all stormwater management facilities. The city may accept dedication of any existing or future stormwater management facility for maintenance, provided such facility meets all the requirements of this ordinance and includes adequate and perpetual access and sufficient area, by easement or otherwise, for inspection and regular maintenance. The city may assign the responsibility to a responsible party.

The responsible party shall enter into an agreement with the city that documents all responsibilities for operation and maintenance of all stormwater treatment facilities. Such responsibility shall be documented in a maintenance plan and executed through a maintenance agreement. The maintenance agreement shall be executed and recorded against the property.

Subd. 2.

Maintenance agreement. The maintenance agreement shall be in a form approved by the city and shall at a minimum:

(a)

Designate the owner or responsible party, which shall be permanently responsible for maintenance of the structural or non-structural measures.

(b)

Pass responsibility for such maintenance to successors in title.

(c)

Grant the city and its representatives the right of entry for the purposes of inspecting all stormwater treatment facilities at reasonable times and in a reasonable manner. This includes the right to enter a property when the city has a reasonable basis to believe that a violation of this division or maintenance agreement is occurring or has occurred and to enter when necessary for the abatement of a public nuisance or correction and enforcement of a violation of this division or agreement.

(d)

Allow the city to repair and maintain the facility, if necessary maintenance is not performed after proper and reasonable notice to the responsible party. The agreement shall permit the city to certify the costs of the maintenance/correction to the taxes for the subject property.

(e)

Include a maintenance plan that contains, but is not limited to the following:

1.

Identification of all structural stormwater treatment facilities.

2.

A schedule for regular inspection, monitoring, and maintenance for each facility. Monitoring shall verify whether the practice is functioning as designed and may include, but is not limited to quantity, temperature and quantity of runoff.

3.

Identification of the responsible party for conducting the inspection, monitoring and maintenance for each facility.

(f)

Identify a schedule and format for reporting compliance with the maintenance plan to the city.

The applicant shall file with the City of Independence a letter of credit or other improvement security in an amount deemed sufficient by the City of Independence to cover all costs of improvements, landscaping, and maintenance of improvements for such period as specified by the City of Independence for engineering and inspection costs and to cover the cost of failure or repair of improvements installed on the site. The amount of the security shall be determined by the city. For commercial development, the security amount shall not be less than 150 percent of the approved estimated cost of performing said work. The estimated cost shall be determined by the city.

Subd. 1.

Stop-work order and revocation of permit. In the event that any person holding a site development permit violates the terms of the permit, or implements site development in such a manner as to materially adversely affect the health, welfare, or safety of persons residing or working in the neighborhood or development site so as to be materially detrimental to the public welfare or injurious to property or improvements in the neighborhood, the city may suspend or revoke the site development permit.

Subd. 2.

Violations and penalties.

(a)

No person shall construct, enlarge, alter, repair, or maintain any grading, excavation, or fill, or cause the same to be done, contrary to or in violation of any terms of this section.

(b)

Any person violating any of the provisions of this ordinance shall be deemed guilty of a misdemeanor, and each day during which any continued or permitted, shall constitute a separate offense.

(c)

In addition to the other penalties authorized by this section, any person, partnership, or corporation convicted of violating any of the provisions of this section shall be required to bear the expense of such restoration.

(d)

The remedies listed in this section are not exclusive of any other remedies available under any applicable federal or state law or other city ordinances and it is within the discretion of the city to seek cumulative remedies.

This ordinance is not intended to interfere with, abrogate, or annul any other ordinance, rule or regulation, statute, or other provision of law. The requirements of this section should be considered minimum requirements, and where any provision of this ordinance imposes restrictions different from those imposed by any other ordinance, rule or regulation, or other provision of law, whichever provisions are more restrictive or impose higher protective standards for human health or the environment shall be considered to take precedence.

If the provisions of any article, section, subsection, paragraph, subdivision or clause of this ordinance shall be judged invalid by a court of competent jurisdiction, such order of judgment shall not affect or invalidate the remainder of any article, section, subsection, paragraph, subdivision or clause of this section.