Chapter 270 Stormwater Management

Editor’s Note: This ordinance also repealed former Ch. 270, Stormwater Management, adopted 8-7-2001 by Ord. No. 1667(15), as amended.

§ 270-1 General provisions.

This chapter is adopted by the Common Council under the authority granted by § 62.234, Wis. Stats.

This chapter supersedes all conflicting and contradictory stormwater management regulations previously enacted under § 62.23, Wis. Stats. Except as specifically provided for in § 62.234, Wis. Stats., § 62.23, Wis. Stats., applies to this chapter and to any amendments to this chapter.

The provisions of this chapter are deemed not to limit any other lawful regulatory powers of the same governing body.

The Common Council hereby designates the City Engineer to administer and enforce the provisions of this chapter.

The requirements of this chapter do not preempt more stringent stormwater management requirements that may be imposed by the administrative rules, permits or approvals of the Department of Natural Resources, including but not limited to those authorized under § 283.33, Wis. Stats.

§ 270-2 Findings of fact.

The Common Council finds that uncontrolled stormwater runoff from land development and land redevelopment activity has a significant impact upon water resources and the health, safety and general welfare of the community and diminishes the public enjoyment and use of natural resources. Specifically, uncontrolled stormwater runoff can:

Degrade physical stream habitat by increasing stream bank erosion, increasing stream bed scour, diminishing groundwater recharge, diminishing stream base flows and increasing stream temperature.

Diminish the capacity of lakes and streams to support fish, aquatic life, and recreational and water supply uses by increasing loadings of sediment, suspended solids, nutrients, heavy metals, bacteria, pathogens and other urban pollutants.

Alter wetland communities by changing wetland hydrology and by increasing pollutant loads.

Reduce the quality of groundwater by increasing pollutant loading.

Threaten public health, safety, property, and general welfare by overtaxing storm sewers, drainageways, and other minor drainage facilities.

Threaten public health, safety, property, and general welfare by increasing major flood peaks and volumes.

Undermine floodplain management efforts by increasing the incidence and levels of flooding.

§ 270-3 Purpose and intent.

Purpose. The general purpose of this chapter is to set forth stormwater requirements and criteria which will diminish the threats to public health, safety and welfare and the aquatic environment due to runoff of stormwater from land development and land redevelopment activity. Specific purposes are to:

Further the maintenance of safe and healthful conditions.

Prevent and control the adverse effects of stormwater, prevent and control soil erosion, prevent and control water pollution, and protect spawning grounds, fish, and aquatic life.

Control exceedance of the safe capacity of existing drainage facilities and receiving water bodies, prevent undue channel erosion, control increases in the scouring and transportation of particulate matter, and prevent conditions that endanger downstream property.

Control building sites, placement of structures, and land uses and promote sound economic growth.

Minimize the amount of pollutants discharged from the separate storm sewer to protect the waters of the state.

Intent. It is the intent of the Common Council that this chapter manage the long-term, post-construction stormwater discharges from land development and land redevelopment activities by achieving a specific set of performance standards at locations where it applies.

This chapter can be applied on a site-by-site basis. The Common Council recognizes, however, that the preferred method of achieving the stormwater performance standards set forth in this chapter is through the preparation and implementation of comprehensive, systems-level stormwater management plans that cover hydrologic units, such as watersheds, on a municipal and regional scale. Such plans may prescribe alternative applicability and performance standards for specific sites when the overall performance standards can be met in a more cost-effective approach.

Where such plans have been developed, and approved by the Common Council, it is the intent of this chapter that land development and redevelopment activity as defined in § 270-4 will be required to meet the stormwater management measures set forth in the approved plan.

Where such stormwater management plans have not been developed, and approved by the Common Council, it is the intent that the stormwater management standards set forth in § 270-7A and B of this chapter be applied unless otherwise excepted by the Common Council.

ADEQUATE SOD OR SELF-SUSTAINING VEGETATIVE COVER

This chapter shall not apply to lands on which the only structures are buildings existing on the effective date of this chapter, which are not redeveloped in a manner that increases discharge volume after the effective date of this chapter.

§ 270-4 Definitions.

As used in this chapter, the following terms shall have the meanings indicated:

Maintenance of sufficient vegetation types and densities such that the physical integrity of the streambank or lakeshore is preserved. "Self-sustaining vegetative cover" includes grasses, forbs, sedges and duff layers of fallen leaves and woody debris.

ADMINISTERING AUTHORITY

The City Engineer is designated by the Common Council to administer this chapter.

AGRICULTURAL ACTIVITY

Planting, growing, cultivating and harvesting of crops for human or livestock consumption and pasturing or yarding of livestock, including sod farms and tree nurseries, but does not include the construction of buildings or facilities used for agriculture.

ATLAS 14

The National Oceanic and Atmospheric Administration (NOAA) Atlas 14 Precipitation-Frequency Atlas of the United States, Volume 8 (Midwestern States), published in 2013.

AVERAGE ANNUAL RAINFALL

A typical calendar year of precipitation as determined by the Wisconsin Department of Natural Resources for users of models such as WinSLAMM, P8 or equivalent methodology. The average annual rainfall is chosen from a department publication for the location closest to the municipality.

BEST MANAGEMENT PRACTICE (BMP)

A practice, technique or measure which is determined to be an effective means of preventing or reducing runoff pollutants to waters of the state, to a level compatible with the performance standards in § 270-7 of this chapter.

BUSINESS DAY

A day the City Engineer's office is normally open for business.

CEASE-AND-DESIST ORDER

A court-issued order to halt land development and land redevelopment activity that is being conducted without the required permit.

COMMON PLAN OF DEVELOPMENT OR SALE

An area where multiple separate and distinct land development activities may be taking place at different times on different schedules but under one plan.

CONNECTED IMPERVIOUSNESS

An impervious surface connected to the waters of the state via a separate storm sewer, an impervious flow path, or a minimally pervious flow path.

CONSTRUCTION SITE

An area upon which one or more land-disturbing construction activities occur, including areas that are part of a larger common plan of development or sale where multiple separate and distinct land-disturbing construction activities may be taking place at different times on different schedules but under one plan. A long-range planning document that describes separate construction projects, such as a twenty-year transportation improvement plan, is not a common plan of development.

DESIGN STORM

A hypothetical discrete rainstorm characterized by a specific duration, temporal distribution, rainfall intensity, return frequency, and total rainfall depth.

DEVELOPMENT

Residential, commercial, industrial or institutional land uses and associated roads.

DIRECT CONDUITS TO GROUNDWATER

Wells, sinkholes, swallets, fractured bedrock at the surface, mine shafts, nonmetallic mines, tile inlets discharging to groundwater, quarries, or depressional groundwater recharge areas over shallow fractured bedrock.

DISCHARGE VOLUME

The quantity of runoff discharged from the land surface as the result of a rainfall event.

EFFECTIVE INFILTRATION AREA

The area of the infiltration system that is used to infiltrate runoff and does not include the area used for site access, berms or pretreatment.

EROSION

The process by which the land's surface is worn away by the action of wind, water, ice or gravity.

EXCEPTIONAL RESOURCE WATERS

Waters listed in § NR 102.11, Wis. Adm. Code.

EXTRATERRATORIAL

The unincorporated area within three miles of the corporate limits of a first-, second-, or third-class city or within 1.5 miles of a fourth-class city or village.

FEE IN LIEU

A monetary payment to the City of Burlington in place of meeting all or part of the stormwater performance standards required by this chapter.

FILTERING LAYER

Soil that has at least a three-foot-deep layer with at least 20% fines; or at least a five-foot-deep layer with at least 10% fines; or an engineered soil with an equivalent level of protection as determined by the regulatory authority for the site.

FINAL STABILIZATION

All land-disturbing construction activities at the construction site have been completed and that a uniform perennial vegetative cover has been established with a density of at least 70% of the cover for the unpaved areas and areas not covered by permanent structures or that employ equivalent permanent stabilization measures.

FINANCIAL GUARANTEE

A performance bond, maintenance bond, surety bond, irrevocable letter of credit, or similar guarantee submitted to the City of Burlington by the permit holder to assure requirements of this chapter are carried out in compliance with the stormwater management plan.

IMPERVIOUS SURFACE

A land cover that releases as runoff all or a large portion of the precipitation that falls on it. Rooftops, sidewalks, driveways, parking lots and streets are examples of surfaces that typically are impervious.

INFILTRATION

The process by which rainfall or surface runoff passes into or through the underlying soil.

INFILTRATION SYSTEM

A device or practice such as a basin, trench, rain garden or swale designed specifically to encourage infiltration, but does not include natural infiltration in pervious surfaces such as lawns, redirecting of rooftop downspouts onto lawns or minimal infiltration from practices, such as swales or roadside channels designed for conveyance and pollutant removal only.

LAND-DISTURBING CONSTRUCTION ACTIVITY

Any man-made alteration of the land surface resulting in a change in the topography or existing vegetative or nonvegetative soil cover, that may result in runoff and lead to an increase in soil erosion and movement of sediment into waters of the state. Land-disturbing construction activity includes clearing and grubbing, demolition, excavating, pit trench dewatering, filling and grading activities.

LANDOWNER

Any person holding fee title, an easement or other interest in property, which allows the person to undertake cropping, livestock management, land-disturbing construction activity or maintenance of stormwater BMPs on the property.

MAINTENANCE AGREEMENT

A legal document that is filed with the County Register of Deeds as a property deed restriction and which provides for long-term maintenance of stormwater management practices.

MAXIMUM EXTENT PRACTICABLE

The highest level of performance that is achievable but is not equivalent to a performance standard identified in this chapter as determined in accordance with § 270-5.1 of this chapter.

NEW DEVELOPMENT

Development resulting from the conversion of previously undeveloped land or agricultural land uses.

NRCS MSE3 or MSE4 DISTRIBUTION

A specific precipitation distribution developed by the United States Department of Agriculture, Natural Resources Conservation Service, using precipitation data from Atlas 14.

OFF SITE

Located outside the property boundary described in the permit application for the land development or land redevelopment activity.

ON SITE

Located within the property boundary described in the permit application for the land development or land redevelopment activity.

ORDINARY HIGH-WATER MARK

Has the meaning given in § NR 115.03(6), Wis. Adm. Code.

OUTSTANDING RESOURCE WATERS

Means waters listed in § NR 102.10, Wis. Adm. Code.

PEAK FLOW DISCHARGE RATE

The maximum unit volume of stormwater discharged during a specified unit of time.

PERFORMANCE STANDARD

A measurable number or measurable narrative for a pollution source that specifies the minimum acceptable outcome for a facility or practice.

PERMIT

A written authorization made by the City of Burlington to the applicant to conduct land development or land redevelopment activities.

PERMIT ADMINISTRATION FEE

A sum of money paid to the City of Burlington by the permit applicant for the purpose of recouping the expenses incurred by the authority in administering the permit.

PERVIOUS SURFACE

A surface that infiltrates rainfall during a large portion of the design rainfall event. Lawns, fields and woodlands are examples of pervious surfaces.

POLLUTANT

Has the meaning given in § 283.01(13), Wis. Stats.

POLLUTION

Has the meaning given in § 281.01(10), Wis. Stats.

POST-CONSTRUCTION SITE

A construction site following the completion of land-disturbing construction activity and final site stabilization.

POST-CONSTRUCTION STORMWATER DISCHARGE

Any stormwater discharged from a site following the completion of land-disturbing construction activity and final site stabilization.

PREDEVELOPMENT CONDITION

The extent and distribution of land cover types present before the initiation of land development or land redevelopment activity, assuming that all land uses prior to development activity are managed in an environmentally sound manner.

PRETREATMENT

The treatment of stormwater prior to its discharge to the primary stormwater treatment practice in order to reduce pollutant loads to a level compatible with the capability of the primary practice.

PROTECTIVE AREA

An area of land that commences at the top of the channel of lakes, streams and rivers, or at the delineated boundary of wetlands, and that is the greatest of the following widths, as measured horizontally from the top of the channel or delineated wetland boundary to the closest impervious surface.

REDEVELOPMENT

Areas where development is replacing older development.

SEPARATE STORM SEWER

A conveyance or system of conveyances including roads with drainage systems, streets, catch basins, curbs, gutters, ditches, constructed channels or storm drains, which meets all of the following criteria:

Is designed or used for collecting water or conveying runoff.

Is not part of a combined sewer system.

Is not part of a publicly owned wastewater treatment works that provides secondary or more stringent treatment.

Discharges directly or indirectly to waters of the state.

SILVICULTURE ACTIVITY

Activities including tree nursery operations, tree harvesting operations, reforestation, tree thinning, prescribed burning, and pest and fire control. Clearing and grubbing of an area of a construction site is not a silviculture activity.

SITE

The entire area included in the legal description of the land on which the land-disturbing construction activity occurred.

STOP-WORK ORDER

An order issued by the City of Burlington which requires that all construction activity on the site be stopped.

STORM SEWER SYSTEM

A conveyance or system of conveyances, including roads with drainage systems, streets, catch basins, curbs, gutters, ditches, constructed channels or storm drains, which is designed for collecting water or conveying stormwater.

STORMWATER MANAGEMENT PLAN

A document that identifies what actions will be taken to reduce stormwater quantity and pollutant loads from land development and land redevelopment activity to levels that meet the purpose and intent of this chapter.

STORMWATER MANAGEMENT SYSTEM PLAN

A comprehensive plan developed to address stormwater drainage and nonpoint source pollution control problems on a watershed or subwatershed basis and which meets the purpose and intent of this chapter.

STORMWATER RUNOFF

That portion of the precipitation falling during a rainfall event or that portion of melting snow that runs off the surface of the land and into the natural or artificial conveyance or drainage network.

TECHNICAL STANDARD

A document that specifies design, predicted performance and operation and maintenance specifications for a material, device or method.

TOP OF THE CHANNEL

An edge, or point on the landscape landward from the ordinary highwater mark of a surface water of the state, where the slope of the land begins to be less than 12% continually for at least 50 feet. If the slope of the land is 12% or less continually for the initial 50 feet landward from the ordinary high-water mark, the top of the channel is the ordinary high-water mark.

TOTAL MAXIMUM DAILY LOAD or TMDL

The amount of pollutants, specified as a function of one or more water quality parameters, that can be discharged per day into a water quality limited segment and still ensure attainment of the applicable water quality standard.

TP-40

Technical Paper No. 40, Rainfall Frequency Atlas of the United States, published in 1961.

TR-55

The United States Department of Agriculture, Natural Resources Conservation Service (previously Soil Conservation Service), Urban Hydrology for Small Watersheds, Second Edition, Technical Release 55, June 1986, which is incorporated by reference for this chapter.

TRANSPORTATION FACILITY

A highway, a railroad, a public mass transit facility, a public-use airport, a public trail or any other public work for transportation purposes such as harbor improvements under § 85.095(1)(b), Wis. Stats. "Transportation facility" does not include building sites for the construction of public buildings and buildings that are places of employment that are regulated by the Department pursuant to § 281.33, Wis. Stats.

TSS

Total suspended solids.

TYPE II DISTRIBUTION

A rainfall type curve as established in the "United States Department of Agriculture, Soil Conservation Service, Technical Paper 149," published in 1973.

WATERS OF THE STATE

Those portions of Lake Michigan and Lake Superior within the boundaries of Wisconsin and all lakes, bays, rivers, streams, springs, ponds, wells, impounding reservoirs, marshes, watercourses, drainage systems and other surface water or groundwater, natural or artificial, public or private, within Wisconsin or its jurisdiction.

§ 270-5 Applicability and jurisdiction.

Applicability. Except as described below, this chapter applies to a post-construction site whereupon one acre or more of land-disturbing construction activity occurs during construction.

Notwithstanding the applicability requirements in Subsection A, this chapter applies to post-construction sites of any size that, as determined by the City Engineer, are likely to result in runoff that exceeds the safe capacity of the existing drainage facilities or receiving body of water, causes undue channel erosion, or increases water pollution by scouring or the transportation of particulate matter.

This chapter applies to construction activities that are smaller than one acre if such activities are part of a larger common plan of development or sale that in total affects one or more acres.

Agricultural facilities and practices are exempt from the provisions of this chapter.

Underground utility construction, but not including the construction of any aboveground structures associated with utility construction, are exempt from the provisions of this chapter.

§ 270-5.1 Applicability of maximum extent practicable.

A post-construction site with less than 10% connected imperviousness, based on the area of land disturbance, provided the cumulative area of all impervious surfaces is less than one acre, is exempt from the provisions of this chapter. However, the exemption of this subsection does not include exemption from the protective area standards of this chapter.

Jurisdiction. This chapter applies to land development and land redevelopment activities within the boundaries of City of Burlington. This chapter applies to all lands located within the extraterritorial plat approval jurisdiction of the City of Burlington, even if plat approval is not involved.

Exclusions. This chapter is not applicable to activities conducted by a state agency, as defined under § 227.01(1), Wis. Stats.

Maximum extent practicable applies when a person who is subject to a performance standard of this chapter demonstrates to the City Engineer's satisfaction that a performance standard is not achievable and that a lower level of performance is appropriate. In making the assertion that a performance standard is not achievable and that a level of performance different from the performance standard is the maximum extent practicable, the responsible party shall take into account the best available technology, cost effectiveness, geographic features, and other competing interests such as protection of public safety and welfare, protection of endangered and threatened resources, and preservation of historic properties.

§ 270-6 Design standards.

Unless prior authorization is given by the City Engineer, the following methods shall be used in designing the water quality, peak discharge, and infiltration components of stormwater practices needed to meet the water quality standards of this chapter:

Consistent with the technical standards identified, developed or disseminated by the Wisconsin Department of Natural Resources under Subchapter V of Ch. NR 151, Wis. Adm. Code.

Where technical standards have not been identified, or developed by the Wisconsin Department of Natural Resources, other technical standards may be used provided that the methods have been approved by the City Engineer.

Maintenance of effort. For redevelopment sites where the redevelopment will be replacing older development that was subject to post-construction performance standards of Ch. NR 151, Wis. Adm. Code, in effect on or after October 1, 2004, the responsible party shall meet the total suspended solids reduction, peak flow control, infiltration, and protective areas standards applicable to the older development or meet the redevelopment standards of this chapter, whichever is more stringent.

A written stormwater management plan in accordance with § 270-9 shall be developed and implemented for each post-construction site.

§ 270-7 Stormwater management standards.

Stormwater discharge quantity. Unless otherwise provided for in this chapter, all land development and land redevelopment activities subject to this chapter shall establish onsite management practices to control the peak flow rates of stormwater discharged from the site and to preserve base flow in streams. The BMPs shall be designed, installed or applied and maintained to the maximum extent practicable in accordance with a stormwater management plan for the long-term control of post-construction stormwater discharges. All of the following apply:

By design, maintain or reduce the peak runoff discharge rates as compared to predevelopment conditions for the one-, two- and ten-year, twenty-four-hour design storms applicable to the site, assuming good hydrologic conditions for predevelopment land covers as identified in TR-55 or an equivalent methodology. Storage shall be provided to accommodate up to a one-hundred-year, twenty-four-hour design storm for post-development land cover with a maximum discharge rate of the ten-year predevelopment rate. Predevelopment runoff curve numbers in Table 1 shall be used. Peak discharges shall be calculated using TR-55 runoff curve number methodology, Atlas 14 precipitation depths, and the appropriate NRCS Wisconsin MSE3 or MSE4 precipitation distribution. On a case-by-case basis, the City Engineer may allow the use of TP-40 precipitation depths and the Type II distribution.

Table 1. Maximum Predevelopment Runoff Curve Numbers
Runoff Curve Number	Hydrologic Soil Group
	A	B	C	D
Woodland	30	55	70	77
Grassland	39	61	71	78
Cropland	55	69	78	83

Discharge velocities must be nonerosive to discharge locations, outfall channels, and receiving streams.

Minimize to the extent practical increases or decreases in the hydrology of wetlands. Where such changes are proposed, the impact of the proposal on wetland functional values shall be assessed using a methodology acceptable to the City Engineer. Significant degradation of wetland functional values shall be avoided. Acceptable assessment methodologies can be found in a guide prepared by the Department of Natural Resources, Water Quality Standards for Wetlands: A Regulator's Guide, Bureau of Water Regulation and Zoning, September 1992.

This subsection of the chapter does not apply to any of the following:

A post-construction site where the discharge is directly into a lake over 5,000 acres or a stream or river segment draining more than 500 square miles;

Except as provided under § 270-6C, a redevelopment post-construction site;

An infill development of less than five acres.

Stormwater discharge quality. Unless otherwise provided for in this chapter, all land development and land redevelopment activities subject to this chapter shall establish onsite management practices to control the discharge of stormwater pollutants. The BMPs shall be designed, installed or applied and maintained in accordance with a stormwater management plan for the long-term control of post-construction stormwater discharges, to control total suspended solids and other pollutants carried in runoff to the maximum extent practicable. All of the following apply:

BMPs shall be designed in accordance with Table 2 or to the maximum extent practicable as provided in Subsection B(6). The design shall be based on an average annual rainfall, as compared to no runoff management controls.

	Table 2. TSS Reduction Standards
	Development Type	TSS Reduction
	New development	80%
	In-fill development	80%
	Redevelopment	40% of load from parking areas and roads

Petroleum products in runoff from gas station pump areas and vehicle maintenance areas shall be controlled with a properly designed and maintained oil and grease separator or other equivalent practice, which shall remove all visible sheen from the runoff prior to discharge to waters of the state. A gas station pump area which has a properly designed canopy that catches and directs stormwater away from the potential spill areas beneath it and the availability and use of petroleum absorbent pads to immediately clean up spills shall be allowed as an equivalent practice to meet this subsection.

Sufficient permanent vegetative cover shall be provided in riparian areas to provide for bank stability, maintenance of fish habitat and filtering of pollutants from upslope overland flow areas. The minimum width of the riparian area is the width calculated using the procedures in NRCS Standard 393, dated January 1995, or 35 feet, whichever is greater. Riparian area widths are measured from the ordinary high-water mark of lakes, streams and wetlands. This subsection is not applicable to redevelopment sites or to structures that cross or access surface waters, such as boat landings, bridges and culverts.

Discharge of urban stormwater pollutants to wetlands from land development and land redevelopment sites shall be minimized to the extent practical. Where such discharges are proposed, the impact of the proposed discharge on wetland functional values shall be assessed using a method acceptable to the City Engineer. At a minimum, stormwater discharges shall be pretreated prior to discharge to wetlands. Significant degradation of wetland functional values due to stormwater pollutant loads shall be avoided.

Stormwater ponds and infiltration devices shall not be located closer to water supply wells than as indicated below without first notifying and obtaining approval from the City Engineer:

One hundred feet from a well serving a private water system or a transient, noncommunity public water system.

One thousand two hundred feet from a well serving a municipal public water system, an other-than municipal public water system, or a nontransient, noncommunity public water system.

The boundary of a recharge area to a wellhead identified in a wellhead area protection plan.

Maximum extent practicable. If the design cannot meet a total suspended solids reduction performance standard of Table 2, the stormwater management plan shall include a written, site-specific explanation of why the total suspended solids reduction performance standard cannot be met and why the total suspended solids load will be reduced only to the maximum extent practicable.

Off-site drainage. When designing BMPs, runoff draining to the BMP from off site shall be taken into account in determining the treatment efficiency of the practice. Any impact on the efficiency shall be compensated for by increasing the size of the BMP accordingly.

Infiltration.

Best management practices. BMPs shall be designed, installed, and maintained to infiltrate runoff in accordance with the following or to the maximum extent practicable:

Low imperviousness. For development up to 40% connected imperviousness, such as parks, cemeteries, and low-density residential development, infiltrate sufficient runoff volume so that the post-development infiltration volume shall be at least 90% of the pre-development infiltration volume, based on an average annual rainfall. However, when designing appropriate infiltration systems to meet this requirement, no more than 1% of the post-construction site is required as an effective infiltration area.

Moderate imperviousness. For development with more than 40% and up to 80% connected imperviousness, such as medium and high density residential, multifamily development, industrial and institutional development, and office parks, infiltrate sufficient runoff volume so that the post-development infiltration volume shall be at least 75% of the pre-development infiltration volume, based on an average annual rainfall. However, when designing appropriate infiltration systems to meet this requirement, no more than 2% of the post-construction site is required as an effective infiltration area.

High imperviousness. For development with more than 80% connected imperviousness, such as commercial strip malls, shopping centers, and commercial downtowns, infiltrate sufficient runoff volume so that the post-development infiltration volume shall be at least 60% of the pre-development infiltration volume, based on an average annual rainfall. However, when designing appropriate infiltration systems to meet this requirement, no more than 2% of the post-construction site is required as an effective infiltration area.

Pre-development. The pre-development condition shall be the same as specified in Table 1 of the peak discharge section of this chapter.

Source areas.

Prohibitions. Runoff from the following areas may not be infiltrated and may not qualify as contributing to meeting the requirements of this section unless demonstrated to meet the conditions identified in § 270-7C(6):

Areas associated with a tier 1 industrial facility identified in § NR 216.21(2)(a), Wis. Adm. Code, including storage, loading and parking. Rooftops may be infiltrated with the concurrence of the regulatory authority.

Storage and loading areas of a tier 2 industrial facility identified in § NR 216.21(2)(b), Wis. Adm. Code.

Fueling and vehicle maintenance areas. Runoff from rooftops of fueling and vehicle maintenance areas may be infiltrated with the concurrence of the regulatory authority.

Exemptions. Runoff from the following areas may be credited toward meeting the requirement when infiltrated, but the decision to infiltrate runoff from these source areas is optional:

Parking areas and access roads less than 5,000 square feet for commercial development.

Parking areas and access roads less than 5,000 square feet for industrial development not subject to the prohibitions under Subsection C(3)(a).

Except as provided under § 270-6C, redevelopment post-construction sites.

[4]

In-fill development areas less than five acres.

[5]

Roads on commercial, industrial and institutional land uses, and arterial residential roads.

Location of practices.

Prohibitions. Infiltration practices may not be located in the following areas:

Areas within 1,000 feet upgradient or within 100 feet downgradient of direct conduits to groundwater.

Areas within 400 feet of a community water system well as specified in § NR 811.16(4), Wis. Adm. Code, or within the separation distances listed in § NR 812.08, Wis. Adm. Code, for any private well or noncommunity well for runoff infiltrated from commercial, including multifamily residential, industrial and institutional land uses or regional devices for one- and two-family residential development.

Areas where contaminants of concern, as defined in § NR 720.03(2), Wis. Adm. Code, are present in the soil through which infiltration will occur.

Separation distances.

Infiltration practices shall be located so that the characteristics of the soil and the separation distance between the bottom of the infiltration system and the elevation of seasonal high groundwater or the top of bedrock are in accordance with Table 3:

Table 3. Separation Distances and Soil Characteristics
Source Area	Separation Distance	Soil Characteristics
Industrial, commercial, institutional parking lots and roads	5 feet or more	Filtering layer
Residential arterial roads	5 feet or more	Filtering layer
Roofs draining to subsurface infiltration practices	1 foot or more	Native or engineered soil with particles finer than coarse sand
Roofs draining to surface infiltration practices	Not applicable	Not applicable
All other impervious source areas	3 feet or more	Filtering layer

Notwithstanding Subsection C(4)(b), applicable requirements for injection wells classified under Ch. NR 815 Wis. Adm. Code, shall be followed.

Infiltration rate exemptions. Infiltration practices located in the following areas may be credited toward meeting the requirements under the following conditions, but the decision to infiltrate under these conditions is optional:

Where the infiltration rate of the soil measured at the proposed bottom of the infiltration system is less than 0.6 inches per hour using a scientifically credible field test method.

Where the least permeable soil horizon to five feet below the proposed bottom of the infiltration system using the United States Department of Agriculture method of soils analysis is one of the following: sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay, or clay.

Alternate use. Where alternate uses of runoff are employed, such as for toilet flushing, laundry, or irrigation or storage on green roofs where an equivalent portion of the runoff is captured permanently by rooftop vegetation, such alternate use shall be given equal credit toward the infiltration volume required by this section.

Groundwater standards.

Infiltration systems designed in accordance with this section shall, to the extent technically and economically feasible, minimize the level of pollutants infiltrating to groundwater and shall maintain compliance with the preventive action limit at a point of standards application in accordance with Ch. NR 140, Wis. Adm. Code. However, if site specific information indicates that compliance with a preventive action limit is not achievable, the infiltration BMP may not be installed or shall be modified to prevent infiltration to the maximum extent practicable.

Notwithstanding Subsection C(6)(a), the discharge from BMPs shall remain below the enforcement standard at the point of standards application.

Pretreatment. Before infiltrating runoff, pretreatment shall be required for parking lot runoff and for runoff from new road construction in commercial, industrial and institutional areas that will enter an infiltration system. The pretreatment shall be designed to protect the infiltration system from clogging prior to scheduled maintenance and to protect groundwater quality in accordance with Subsection C(6). Pretreatment options may include, but are not limited to, oil and grease separation, sedimentation, biofiltration, filtration, swales or filter strips.

Maximum extent practicable. Where the conditions of Subsection C(3) and (4) limit or restrict the use of infiltration practices, the performance standard of § 270-7C shall be met to the maximum extent practicable.

Protective areas.

Definition. In this section, "protective area" means an area of land that commences at the top of the channel of lakes, streams and rivers, or at the delineated boundary of wetlands, and that is the greatest of the following widths, as measured horizontally from the top of the channel or delineated wetland boundary to the closest impervious surface. However, in this section, "protective area" does not include any area of land adjacent to any stream enclosed within a pipe or culvert, so that runoff cannot enter the enclosure at this location.

For outstanding resource waters and exceptional resource waters, 75 feet.

For perennial and intermittent streams identified on a United States Geological Survey 7.5-minute series topographic map, or a county soil survey map, whichever is more current, 50 feet.

For lakes, 50 feet.

(d)

For wetlands not subject to Subsection D(1)(e) or (f), 50 feet.

(e)

For highly susceptible wetlands, 75 feet. Highly susceptible wetlands include the following types: calcareous fens, sedge meadows, open and coniferous bogs, low prairies, coniferous swamps, lowland hardwood swamps, and ephemeral ponds.

(f)

For less susceptible wetlands, 10% of the average wetland width, but no less than 10 feet nor more than 30 feet. Less susceptible wetlands include: degraded wetland dominated by invasive species such as reed canary grass; cultivated hydric soils; and any gravel pits, or dredged material or fill material disposal sites that take on the attributes of a wetland.

(g)

In Subsection D(1)(d) to (f), determinations of the extent of the protective area adjacent to wetlands shall be made on the basis of the sensitivity and runoff susceptibility of the wetland in accordance with the standards and criteria in § NR 103.03, Wis. Adm. Code.

(h)

Wetland boundary delineation shall be made in accordance with § NR 103.08 (1m), Wis. Adm. Code. This subsection does not apply to wetlands that have been completely filled in compliance with all applicable state and federal regulations. The protective area for wetlands that have been partially filled in compliance with all applicable state and federal regulations shall be measured from the wetland boundary delineation after a fill has been placed. Where there is a legally authorized wetland fill, the protective area standard need not be met in that location.

(i)

For concentrated flow channels with drainage areas greater than 130 acres, 10 feet.

(j)

Notwithstanding Subsection D(1)(a) to (i), the greatest protective area width shall apply where rivers, streams, lakes and wetlands are contiguous.

Applicability. This section applies to post-construction sites located within a protective area, except those areas exempted pursuant to Subsection D(4).

Requirements. The following requirements shall be met:

Impervious surfaces shall be kept out of the protective area entirely or to the maximum extent practicable. If there is no practical alternative to locating an impervious surface in the protective area, the stormwater management plan shall contain a written, site-specific explanation.

Where land-disturbing construction activity occurs within a protective area, adequate sod or self-sustaining vegetative cover of 70% or greater shall be established and maintained where no impervious surface is present. The adequate sod or self-sustaining vegetative cover shall be sufficient to provide for bank stability, maintenance of fish habitat, and filtering of pollutants from upslope overland flow areas under sheet flow conditions. Non-vegetative materials, such as rock riprap, may be employed on the bank as necessary to prevent erosion such as on steep slopes or where high velocity flows occur.

BMPs such as filter strips, swales, or wet detention ponds, that are designed to control pollutants from nonpoint sources, may be located in the protective area.

Exemptions. This section does not apply to any of the following:

Except as provided under § 270-6C, redevelopment post-construction sites.

In-fill development areas less than five acres.

Structures that cross or access surface water such as boat landings, bridges, and culverts.

(d)

Structures constructed in accordance with § 59.692(1v), Wis. Stats.

(e)

Areas of post-construction sites from which the runoff does not enter the surface water, including wetlands, without first being treated by a BMP to meet the local ordinance requirements for total suspended solids and peak flow reduction, except to the extent that vegetative ground cover is necessary to maintain bank stability.

Swale treatment for transportation facilities.

Requirement. Except as provided in Subsection E(2), transportation facilities that use swales for runoff conveyance and pollutant removal are exempt from the requirements of local ordinance requirements for peak flow control, total suspended solids control, and infiltration, if the swales are designed to do all of the following or to the maximum extent practicable:

Swales shall be vegetated. However, where appropriate, nonvegetative measures may be employed to prevent erosion or provide for runoff treatment, such as rock riprap stabilization or check dams.

Swales shall comply with sections V.F. (Velocity and Depth) and V.G. (Sale Geometry Criteria) with a swale treatment length as long as that specified in section V.C. (Pre-Treatment) of the Wisconsin Department of Natural Resources Technical Standard 1005 "Vegetated Infiltration Swales," dated May 2007, or a superseding document. Transportation facility swale treatment does not have to comply with other sections of Technical Standard 1005.

Other requirements.

Notwithstanding Subsection E(1), the administering authority may, consistent with water quality standards, require that other requirements, in addition to swale treatment, be met on a transportation facility with an average daily traffic rate greater than 2,500 and where the initial surface water of the state that the runoff directly enters is one of the following:

An outstanding resource water.

An exceptional resource water.

Waters listed in § 303(d) of the Federal Clean Water Act that are identified as impaired, in whole or in part, due to nonpoint source impacts.

[4]

Water where targeted performance standards are developed pursuant to § NR 151.004, Wis. Adm. Code.

The transportation facility authority shall contact the City Engineer to determine if additional BMPs beyond a water quality swale are needed under this subsection.

General considerations for stormwater management measures. The following considerations shall be observed in on-site and off-site runoff management:

Natural topography and land cover features such as natural swales, natural depressions, native soil infiltrating capacity, and natural groundwater recharge areas shall be preserved and used, to the extent possible, to meet the requirements of this section.

Emergency overland flow for all stormwater facilities shall be provided to prevent exceeding the safe capacity of downstream drainage facilities and prevent endangerment of downstream property or public safety.

BMP location.

To comply with the performance standards required under § 270-7 of this chapter, BMPs may be located on-site or off-site as part of a regional stormwater device, practice or system, but shall be installed in accordance with § NR 151.003, Wis. Adm. Code.

The City Engineer may approve off-site management measures provided that all of the following conditions are met:

The City Engineer determines that the post-construction runoff is covered by a stormwater management system plan that is approved by the City of Burlington and that contains management requirements consistent with the purpose and intent of this chapter.

The off-site facility meets all of the following conditions:

The facility is in place.

The facility is designed and adequately sized to provide a level of stormwater control equal to or greater than that which would be afforded by on-site practices meeting the performance standards of this chapter.

The facility has a legally obligated entity responsible for its long-term operation and maintenance.

Where a regional treatment option exists such that the City Engineer exempts the applicant from all or part of the minimum on-site stormwater management requirements, the applicant shall be required to pay a fee in an amount determined in negotiation with the City Engineer. In determining the fee for post-construction runoff, the City Engineer shall consider an equitable distribution of the cost for land, engineering design, construction, and maintenance of the regional treatment option.

Exceptions. The City Engineer may establish stormwater management requirements either more stringent or less stringent than those set forth in Subsections A and B, provided that at least one of the following conditions applies:

The City Engineer determines that an added level of protection is needed to protect sensitive resources.

The City Engineer determines that the land development and land redevelopment activity is covered by an approved stormwater management system plan that contains management requirements consistent with the purpose and intent of this chapter.

Provisions are made to manage stormwater by an off-site facility, provided that all of the following conditions for the off-site facility are met:

The facility is in place.

The facility has a legally obligated entity responsible for its long-term operation and maintenance.

The City Engineer finds that meeting the minimum on-site management requirements of this chapter is not feasible due to space or site restrictions.

Fee in lieu of on-site stormwater management practices. Where the City Engineer waives under § 270-8C all or part of the minimum on-site stormwater management requirements, notwithstanding § 270-8C(1), the applicant shall be required to pay a fee in an amount determined in negotiation with the City of Burlington and approved by the Common Council. The purpose of the fee is to fund alternative municipal stormwater management measures to offset the environmental and flooding impacts of waiving the requirements. In determining the fee for land development and land redevelopment projects, the City shall consider an equitable distribution of the cost needed for land, engineering design, construction, and maintenance of stormwater management practices. All such fees collected shall be placed in a designated fund to be used exclusively for the City stormwater management practices to be constructed.

§ 270-8 Permit procedure.

Permit required. No landowner or land operator may undertake a land development or land redevelopment activity subject to this chapter without receiving a permit from the City prior to commencing the proposed activity.

Permit application and fee. Unless specifically excluded by this chapter, any landowner or operator desiring a permit shall submit to the City a permit application made on a form provided by the City of Burlington for that purpose.

Unless otherwise excepted by this chapter, a permit application must be accompanied by the following in order for the permit application to be considered for approval by the City Engineer: a stormwater management plan, a maintenance agreement, a financial guarantee and a nonrefundable permit administration fee established in § 270-12 of this chapter.

The stormwater management plan shall be prepared to meet the requirements of §§ 270-7 and 270-9 of this chapter. The maintenance agreement shall be prepared to meet the requirements of § 270-10 of this chapter, the financial guarantee shall meet the requirements of § 270-11 of this chapter, and fees shall be those established by the Common Council as set forth in § 270-12 of this chapter.

Review and approval of permit application. The City Engineer shall review any permit application that is submitted with a stormwater management plan, maintenance agreement, and the required fee. The following approval procedure shall be used:

Within 30 days of the receipt of a complete permit application, including all items as required by Subsection B(1), the City Engineer shall inform the applicant whether the application, plan and maintenance agreement are approved or disapproved. The City Engineer shall base the decision on requirements set forth in §§ 270-7, 270-9 and 270-10 of this chapter.

If the stormwater permit application, plan and maintenance agreement are approved, or if an agreed-upon payment of fees in lieu of stormwater management practices is made, the City shall issue the permit.

If the stormwater permit application, plan or maintenance agreement are not approved, the City Engineer shall write in detail the reasons.

The City Engineer may request additional information from the applicant. If additional information is submitted, the City Engineer shall have 15 days from the date the additional information is received to inform the applicant that the plan and maintenance agreement are either approved or disapproved.

Permit conditions. All permits issued under this chapter shall be subject to the following conditions, and holders of permits issued under this chapter shall be deemed to have accepted these conditions. The City Engineer may suspend or revoke a permit for violation of a permit condition, following written notification of the permittee. An action by the City to suspend or revoke this permit may be appealed in accordance with § 270-14 of this chapter.

Compliance with this permit does not relieve the permit holder of the responsibility to comply with other applicable federal, state, and local laws and regulations.

The permit holder shall design and install all structural and nonstructural stormwater management measures in accordance with the approved stormwater management plan and this permit.

The permit holder shall notify the City at least two business days before commencing any work in conjunction with the stormwater management plan and within five business days upon completion of the stormwater management practices. If required as a special condition under Subsection D(4), the permit holder shall make additional notification according to a schedule set forth by the City Engineer so that practice installations can be inspected during construction.

Permits issued under this section may include any special conditions needed to meet the performance standards in § 270-7 or a financial guarantee as provided for in § 270-11 of this chapter.

Stormwater practice installations required as part of this chapter shall be certified "as built" by a licensed professional engineer. Completed stormwater management practices must pass a final inspection by the City Engineer or his designee to determine if they are in accordance with the approved stormwater management plan and this chapter. The City Engineer or his designee shall notify the permit holder in writing of any changes required in such practices to bring them into compliance with the conditions of this permit.

The permit holder shall notify the City Engineer of any significant modifications it intends to make to an approved stormwater management plan. The City Engineer will require that the proposed modifications be submitted for approval prior to incorporation into the stormwater management plan and execution.

The permit holder shall maintain all stormwater management practices in accordance with the stormwater management plan until the practices either become the responsibility of the City of Burlington or are transferred to subsequent private owners as specified in the approved maintenance agreement.

The permit holder authorizes the City Engineer to perform any work or operations necessary to bring stormwater management measures into conformance with the approved stormwater management plan and consents to a special assessment or charge against the property as authorized under § 66.0627, Wis. Stats., or to charging such costs against the financial guarantee posted under § 270-11 of this chapter.

(9)

If so directed by the City Engineer, the permit holder shall repair, at the permit holder's own expense, all damage to adjoining private and municipal facilities and drainageways caused by stormwater runoff, where such damage is caused by activities that are not in compliance with the approved stormwater management plan.

(10)

The permit holder shall permit property access to the City Engineer or his designee for the purpose of inspecting the property for compliance with the approved stormwater management plan and this permit.

(11)

Where a stormwater management plan involves changes in direction or increases in peak rate and/or total volume of runoff from a site, the City Engineer will require the permittee to make appropriate legal arrangements with affected property owners concerning the prevention of endangerment to property or public safety.

(12)

The permit holder is subject to the actions detailed in § 270-13 of this chapter if the permit holder fails to comply with the terms of this permit.

Permit duration. Permits issued under this section shall be valid from the date of issuance through the date the City Engineer notifies the permit holder that all stormwater management practices have passed the final inspection. If work is not commenced within 180 days, the permit shall expire. The City Engineer may attach additional conditions before reissuing a permit.

§ 270-9 Stormwater management plan.

Plan requirements. The stormwater management plan required under § 270-8B(1) of this chapter shall contain any information the City Engineer requires to evaluate the environmental characteristics of the area affected by land development and land redevelopment activity, the potential impacts of the proposed development upon the quality and quantity of stormwater discharges, the potential impacts upon water resources and drainage utilities, and the effectiveness and acceptability of proposed stormwater management measures in meeting the performance standards set forth in this chapter. Unless specified otherwise by this chapter, stormwater management plans shall contain at a minimum the following information:

Name, address, telephone number, fax number and e-mail address for the following or their designees; landowner, developer, project engineer for practice design and certification, person(s) responsible for installation of stormwater management practices, and person(s) responsible for maintenance of stormwater management practices prior to the transfer, if any, of maintenance responsibility to another party.

A proper legal description of the property proposed to be developed referenced to the United States Public Land Survey system or to block and lot numbers within a recorded land subdivision plat. Include a USGS 7.5 minute topographical map showing the property boundaries of the proposed development.

Predevelopment site conditions, including:

One or more site maps at a scale of not less than one inch equals 100 feet. The site maps shall show the following: site location and legal property description; predominant soil types and hydrologic soil groups; existing cover type and condition; topographic contours of the site at a scale not to exceed two feet; topography and drainage network, including enough of the contiguous properties to show runoff patterns onto, through and from the site; watercourses that may affect or be affected by runoff from the site; flow path and direction for all stormwater conveyance sections, including time of travel and time of concentration applicable to each; watershed boundaries used in determinations of peak flow discharge rates and discharge volumes from the site; lakes, streams, wetlands, channels, ditches, and other watercourses on and immediately adjacent to the site; limits of the one-hundred-year floodplain; location of wells located within 1,200 feet of stormwater detention ponds, infiltration basins, or infiltration trenches; and wellhead protection areas covering the project area and delineated pursuant to § NR 811.16, Wis. Adm. Code.

Computations of peak flow discharge rates and discharge volumes for the two- and ten-year, twenty-four-hour storm events. All major assumptions used in developing input parameters shall be clearly stated. The computations shall be made for each discharge point in the development, and the geographic areas used in making the calculations shall be clearly cross-referenced to the required map(s).

Post-development site conditions, including:

Explanation of the provisions to preserve and use natural topography and land cover features to minimize changes in peak flow runoff rates and volumes to surface waters and wetlands.

Explanation of any restrictions on stormwater management measures in the development area imposed by wellhead protection plans and ordinances.

One or more site maps at a scale of not less than one inch equals 100 feet showing the following: post-construction pervious land use, including vegetative cover type and condition; impervious land use, including all buildings, structures, and pavement; post-construction topographic contours of the site at a scale not to exceed two feet; post-construction drainage network, including enough of the contiguous properties to show runoff patterns onto, through and from the site; locations and dimensions of drainage easements; locations of maintenance easements specified in the maintenance agreement; flow path and direction for all stormwater conveyance sections, including time of travel and time of concentration applicable to each; location and type of all stormwater management conveyance and treatment practices, including the on-site and off-site tributary drainage area; location and type of conveyance system that will carry runoff from the drainage and treatment practices to the nearest adequate outlet, such as a curbed street, storm drain, or natural drainageway; watershed boundaries used in determinations of peak flow discharge rates and discharge volumes; any changes to lakes, streams, wetlands, channels, ditches, and other watercourses on and immediately adjacent to the site.

(d)

Computations of peak flow discharge rates for the two-, ten- and one-hundred-year, twenty-four-hour storm events and computation for storage of the one-hundred-year, twenty-four-hour storm event with a maximum ten-year predevelopment discharge rate. All major assumptions used in developing input parameters shall be clearly stated. The computations of peak flow discharge rates shall be made for each discharge point in the development, and the geographic areas used in making the calculations shall be clearly cross-referenced to the required map(s).

(e)

Results of investigations of soils and groundwater required for the placement and design of stormwater management measures.

(f)

Results of impact assessments on wetland functional values.

(g)

Design computations and all applicable assumptions for the storm sewer system.

(h)

Design computations and all applicable assumptions for stormwater quality practices as needed to show that practices are appropriately sized to meet the performance standards of this chapter.

(i)

Detailed drawings, including cross sections and profiles of all permanent stormwater conveyance and treatment practices.

A description and installation schedule for the stormwater management practices needed to meet the performance standards in § 270-7.

A maintenance plan developed for the life of each stormwater management practice, including the required maintenance activities and maintenance activity schedule.

Cost estimates for the construction, operation, and maintenance of each stormwater management practice.

Other information requested in writing by the City Engineer to determine compliance of the proposed stormwater management measures with the provisions of this chapter.

All site investigations, plans, designs, computations, and drawings shall be certified by a licensed professional engineer to be prepared in accordance with accepted engineering practice and requirements of this chapter.

Exceptions. The City Engineer may prescribe alternative submittal requirements for applicants seeking an exemption to on-site stormwater management performance standards under § 270-7C of this chapter.

§ 270-10 Maintenance agreement.

Maintenance agreement required. The maintenance agreement required for stormwater management practices under § 270-8B of this chapter shall be an agreement between the City and the permittee to provide for maintenance of stormwater practices beyond the duration period of this permit. The agreement or recordable document shall be recorded with the County Register of Deeds so that it is binding upon all subsequent owners of land served by the stormwater management practices.

Agreement provisions. The maintenance agreement shall contain the following information and provisions:

Identification of the stormwater facilities and designation of the drainage area served by the facilities.

A schedule for regular maintenance of each aspect of the stormwater management system consistent with the stormwater management plan required under § 270-8B.

Identification of the landowner(s), organization or municipality responsible for long-term maintenance of the stormwater management practices identified in the stormwater plan required under § 270-8B.

Requirement that the landowner(s), organization, or municipality shall maintain stormwater management practices in accordance with the schedule included in Subsection B(2).

Authorization for the City to access the property to conduct inspections of stormwater practices as necessary to ascertain that the practices are being maintained and operated in accordance with the agreement.

A requirement that the City shall maintain public records of the results of the site inspections, shall inform the landowner responsible for maintenance of the inspection results, and shall specifically indicate any corrective actions required to bring the stormwater management practice into proper working condition.

Agreement that the City notify the party designated under the maintenance agreement of maintenance problems which require correction. The specified corrective actions shall be taken within a reasonable time frame as set by the City Engineer.

Authorization of the City to perform the corrected actions identified in the inspection report if the landowner does not make the required corrections in the specified time period. The City Treasurer shall enter the amount due on the tax rolls and collect the money as a special charge against the property pursuant to § 66.0627, Wis. Stats.

§ 270-11 Financial guarantee.

Establishment of guarantee. The City of Burlington may require the submittal of a financial guarantee, the form and type of which shall be acceptable to the City Attorney, and which generally shall be an irrevocable letter of credit. The financial guarantee shall be in an amount determined by the City to be the estimated cost of construction and the estimated cost of maintenance of the stormwater management practices during the period which the designated party in the maintenance agreement has maintenance responsibility. The financial guarantee shall give the City the authorization to use the funds to complete the stormwater management practices if the landowner defaults or does not properly implement the approved stormwater management plan, upon written notice to the landowner by the administering authority that the requirements of this chapter have not been met.

Conditions for release. Conditions for the release of the financial guarantee are as follows: