28.040 Definitions.

Administering authority means the City’s Director of Public Works, or his/her designee to administer this chapter.

Agricultural activity area means the part of a farm where there is planting, growing, cultivating and harvesting of crops for human or livestock consumption and pasturing or outside yarding of livestock, including sod farms and silviculture. Practices in this area may include waterways, drainage ditches, diversions, terraces, farm lanes, excavation, filling and similar practices. The agricultural activity area does not include the agricultural production area.

Applicant means any public or private property owner, tenant, developer or agent responsible for submitting and carrying out the requirements of this chapter. Applicant shall also mean any subsequent landowner to which this chapter applies.

Average annual rainfall means a calendar year of precipitation, excluding snow, which is considered typical. For purposes of this chapter, average annual rainfall means measured precipitation in Green Bay, Wisconsin, between March 29 and November 25, 1969.

Best management practices or BMP means structural or nonstructural measures, practices, techniques or devices employed to avoid or minimize sediment or pollutants in runoff to waters of the State.

Business day means a day on which offices of the City are routinely and customarily open for business.

Cease and desist order means a court-issued order to halt land disturbing construction activity that is being conducted without the required permit.

City means the City of Manitowoc, Wisconsin.

Common plan of development or sale means all lands included within the boundary of a Certified Survey Map or subdivision plat pursuant to Chapter 21 MMC and Wis. Stat. Ch. 236, created for the development or sale of property, where multiple, separate, and distinct land developing activities may take place at a different times and on different schedules.

Connected imperviousness means an impervious surface that is directly connected to a separate storm sewer or water of the State via an impervious flow path.

Construction site means 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.

Design rainfall event means a discrete rainstorm characterized by a specific duration, rainfall intensity and/or return frequency.

Design storm means a hypothetical discrete rainstorm characterized by a specific duration, temporal distribution, rainfall intensity, return frequency, and total depth of rainfall. The TR-55, Type II, 24-hour design storms for the City of Manitowoc are: one-year, 2.2 inches; two-year, 2.4 inches; five-year, 3.3 inches; 10-year, 3.7 inches; 25-year, 4.4 inches; and 100-year, five inches.

Director of Public Works means the City of Manitowoc Director of Public Works or designee.

Discharge volume means the quantity of runoff discharged from the land surface as the result of a rainfall event.

Division of land means the creation of an additional legal lot of record or a building site within the City or its extraterritorial jurisdiction.

Effective infiltration area means 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 means the process by which the land’s surface is worn away by the action of wind, water, ice or gravity.

Existing land use condition means the use of a lot or structure, or the condition of the proposed development site and adjacent properties that are present prior to the contemplated development or site alteration. This term applies for the purpose of properly sizing the stormwater conveyance system in accordance with the requirements of this chapter.

Extraterritorial means the unincorporated area within three miles of the corporate limits of the City pursuant to Wis. Stat. § 62.23(7a).

Fee-in-lieu means a payment of money, land dedication or other consideration acceptable to the City, in place of meeting all or part of the stormwater performance standards required by this chapter.

Final stabilization means that 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 percent of the cover, for the unpaved areas and areas not covered by permanent structures, or employment of equivalent permanent stabilization measures.

Future proposed land use or post-development conditions means any proposed land alterations or disturbances including, but not limited to, the removal of vegetative cover; excavating; filling/grading; and the construction of buildings, roads, parking lots, paved storage areas and similar facilities.

Gross aggregate area means the total area, in acres, of all land located within the property boundary or the common plan of development or sale containing the land development activity, as measured by the outside dimensions of said property.

Groundwater enforcement standard means a numerical value expressing the concentration of a substance in groundwater, which is adopted under Wis. Stat. § 160.07, and Wis. Admin. Code NR 140.10 or Wis. Stat. § 160.09, and Wis. Admin. Code NR 140.12.

Groundwater preventive action limit means a numerical value expressing the concentration of a substance in groundwater that is adopted under Wis. Stat. § 160.15, and Wis. Admin. Code NR 140.12 or 140.20.

Impervious surface means a surface that severely reduces or does not allow infiltration during precipitation events. Rooftops, sidewalks, parking lots, and street surfaces are examples of impervious surface. Gravel surfaces are considered impervious.

In-fill area means a new development area less than five acres in size that is located within existing urban sewer service areas, surrounded by already existing development or existing development and natural or manmade features where development cannot occur.

Infiltration means the process by which rain or surface runoff penetrates into the underlying soil.

Infiltration system means 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 road side channels, designed for conveyance and pollutant removal only.

Karst feature means an area or surficial geologic feature subject to bedrock dissolution so that it is likely to provide a conduit to groundwater, and may include caves, enlarged fractures, mine features, exposed bedrock surfaces, sinkholes, springs, seeps or swallets.

Land development activity means any activity that changes the volume or peak flow discharge rate of rainfall runoff from the land surface. This term does not include agricultural cropping activities.

Land disturbing construction activity (or disturbance) means any manmade 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, and soil stockpiling.

Maintenance agreement means a legal document approved by the City that is recorded at the Manitowoc County Register of Deeds as a property deed restriction, and which provides for long-term maintenance of stormwater management practices.

MEP or maximum extent practicable means a level of implementing best management practices in order to achieve a performance standard specified in this chapter which takes into account the best available technology, cost effectiveness and other competing issues such as human safety and welfare, endangered and threatened resources, historic properties and geographic features. MEP allows flexibility in the way to meet the performance standards and may vary based on the performance standard and site conditions.

Natural wetlands means an area where water is at, near, or above the land surface long enough to be capable of supporting aquatic or hydrophytic vegetation, and which has soils indicative of wet conditions. These wetlands include existing, mitigated and restored wetlands.

New development means that portion of a post-construction site where impervious surfaces are being created or expanded. Any disturbance where the amount of impervious area for the post-development condition is greater than the predevelopment condition is classified as new development. For purposes of this chapter, a post-construction site is classified as new development, redevelopment, routine maintenance, or some combination of these three classifications as appropriate.

Nonstormwater discharge means a discharge to the storm sewer system created by a process other than the runoff from precipitation.

Nonstructural measure means a practice, technique, or measure to reduce the volume, peak flow rate, or pollutants in stormwater that does not require the design or installation of fixed stormwater management facilities.

Off-site means lands located outside the property boundary described in the permit application for land development activity, or in a site plan approved pursuant to MMC 15.370(2).

On-site means located within the property boundary described in the permit application, or in a site plan approved pursuant to MMC 15.370(2).

Other than residential development means development of the following land uses: retail; commercial; industrial; government and institutional; recreation; transportation, communication, and utilities, or mixed use being a combination of the above.

Peak flow discharge rate means the maximum rate at which a unit volume of stormwater is discharged.

Permit means a written authorization made by the City to the applicant to conduct land development activities.

Permit administration fee means a sum of money paid to the City by the permit applicant for the purpose of partially or fully recouping the expenses incurred by the City in administering the permit.

Pervious surface means a surface that allows infiltration of precipitation or surface flow. Lawns, fields and woodlands are examples of pervious surfaces.

Post-construction stormwater discharge means any stormwater discharged from a site following the completion of land disturbing construction activity and final site stabilization.

Post-development land use condition means the extent and distribution of land cover types, anticipated to occur under conditions of full development, that will influence precipitation runoff and infiltration (see also future proposed land use condition).

Predevelopment land use condition means land which has runoff characteristics equivalent to runoff curve numbers (CNs) of: 30, 58, 71, and 78 for hydrologic soil groups A, B, C, and D, respectively. This term is used for the purpose of matching of pre- and post-development stormwater peak flows and volumes as required by this chapter. MMC 28.060(2)(a) (see also existing land use condition).

Pretreatment means the treatment of stormwater prior to its discharge to wetlands, infiltration practices, or the primary stormwater treatment practice in order to reduce pollutant loads to a level compatible with the capability of the wetland, infiltration or primary stormwater treatment practice.

Public drainage system means all facilities owned and operated by the City, Manitowoc County or the Wisconsin Department of Transportation for the purpose of collecting, conveying, storing, treating and properly disposing of stormwater runoff.

Redevelopment means areas where development is replacing older development.

Residential land development means residential dwellings as well as all affected portions of a development including lawns, driveways, sidewalks, garages, and access streets. This type of development includes single- and two-family, multifamily, condominium, apartment, mobile and manufactured homes.

Responsible party means any entity holding fee title to the property or other person contracted or obligated by other agreement to implement and maintain post-construction stormwater BMPs.

Routine maintenance means that portion of a post-construction site where predevelopment impervious surfaces are being maintained to preserve the original line and grade, hydraulic capacity, drainage pattern, configuration, or purpose of the facility. Remodeling of buildings and resurfacing of parking lots, streets, driveways, and sidewalks are examples of routine maintenance, provided the lower one-half of the impervious surface’s granular base is not disturbed. The disturbance shall be classified as redevelopment if the lower one-half of the granular base associated with the predevelopment impervious surface is disturbed or if the soil located beneath the impervious surface is exposed. For purposes of this chapter, a post-construction site is classified as new development, redevelopment, routine maintenance, or some combination of these three classifications as appropriate.

Runoff means stormwater or precipitation including rain, snow or ice melt or similar water that moves on the land surface via sheet or channelized flow.

Security instrument means an irrevocable letter of credit, or similar financial guarantee, submitted to the City by the permit holder meeting the requirements under MMC 15.370(2)(l), to assure that installation and maintenance requirements of this chapter are carried out in compliance with the stormwater management plan. The Director of Public Works must preapprove the security instrument.

Separate storm sewer means 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:

(a) Is designed or used for collecting water or conveying runoff.

(b) Is not part of a combined sewer system.

(c) Is not draining to a stormwater treatment device or system.

(d) Discharges directly or indirectly to waters of the State.

Significant modification to practice or installation means any alteration that alters the performance of the practice or installation by more than five percent (based upon cost, efficiency, or effectiveness) or alters the method of practice or installation.

Site means the entire area included in the legal description of the land on which the land disturbing construction activity occurred or lands covered by a site plan pursuant to MMC 15.370(2).

Site restrictions means any physical characteristics that limit the use of a stormwater best management practice.

Stop work order means a written order issued by the City which requires all construction activity at a site be stopped.

Stormwater conveyance system means any method employed to hold, carry or transport stormwater runoff from a development to waters of the State. Examples of methods include swales, channels, and storm sewers.

Stormwater management measure means structural or nonstructural practices that are designed to reduce stormwater runoff pollutant loads, discharge volumes, and peak flow discharge rates.

Stormwater management plan means a document that identifies what actions will be taken to reduce stormwater quantity and pollutant loads from the post-development land use condition to levels meeting the requirements of this chapter.

Stormwater management system plan is a comprehensive plan designed to reduce the discharge of runoff and pollutants from hydrologic units on a regional or municipal scale.

Stormwater runoff means that portion of precipitation that does not soak into the soil, and flows off the surface of the land and into the natural or artificial conveyance system.

Structural measure means source area practices, conveyance measures, and end-of-pipe treatment that are designed to control stormwater runoff pollutant loads, discharge volumes, and peak flow rates.

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

Top of the channel means an edge, or point on the landscape, landward from the ordinary high-water mark of a surface water of the State, where the slope of the land begins to be less than 12 percent continually for at least 50 feet. If the slope of the land is 12 percent 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.

TR-55 means 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.

Transportation facility means a public street, a public road, a public highway, 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 Wis. Stat. § 85.095(1)(b).

Type II distribution means a rainfall type curve as established in the United States Department of Agriculture, Soil Conservation Service, Technical Paper 149, published 1973. The Type II curve is applicable to all of Wisconsin and represents the most intense storm pattern.

Waters of the State has the meaning given in Wis. Stat. § 281.01(18).

Wetland functional value means the type, quality, and significance of the ecological and cultural benefits provided by wetland resources, including, but not limited to, flood storage, water quality protection, groundwater recharge and discharge, shoreline protection, fish and wildlife habitat, floral diversity, aesthetics, recreation, and education.

WPDES means Wisconsin Pollutant Discharge Elimination System.

WPDES Stormwater Permit means a permit issued by the Wisconsin Department of Natural Resources under Wis. Stat. § 283.33 that authorizes the point source discharge of stormwater to waters of the State, and is regulated by Wis. Admin. Code NR 216, “Stormwater Discharge Permit.”

[Ord. 16-741 § 18, 2016; Ord. 08-522 § 4, 2008. Prior code § 28.04]