Definitions

MINNEHAHA CREEK WATERSHED DISTRICT BOARD OF MANAGERS

DEFINITIONS AND ACRONYMS RULE PURSUANT TO MINNESOTA STATUTES §103D.341

Adopted April 11, 2024
Effective April 29, 2024

Key definitions

• Agricultural activity means the use of land to produce agronomic, horticultural or silvicultural crops, including nursery stock, sod, fruits, vegetables, flowers, forages, cover crops, grains, and Christmas trees, or for grazing.
• Alteration or alter means to change or diminish the course, current, or cross-section of a public water or wetland.
• BMP (best management practice) is an action, or a structural or non-structural method, to prevent or limit adverse impact to water resources that is recognized by those proficient in the field as reflecting best present means and methods.
• Bed of a waterbody means that part of a waterbody located below the ordinary high-water level.
• Bioengineering Practice means the strategic installation of natural, vegetative, biologically active materials in conjunction with toe stabilization, riprap or other hard-armoring materials to stabilize a shoreline or streambank area and associated slopes and prevent erosion.
• Biological Practice means the strategic placement of natural, vegetative, biologically active materials – such as but not limited to brush mattresses, live stakes/plantings, brush layering, fiber rolls, root wads and willow wattles – to stabilize a shoreline or streambank area and prevent erosion.
• Common plan of development means one proposed plan for a contiguous area where multiple separate and distinct land-disturbing activities may be taking place at different times, on different schedules, but under one proposed plan. One plan is broadly defined to include design, permit application, advertisement or physical demarcation indicating that land-disturbing activities may occur.
• Design Storm means a storm magnitude with a return period (T) that has the probability (1/T) of being equaled or exceeded in a given year. For example, a “100-year” event at a given location has a chance of 1/100 or 0.01 or 1% of being equaled or exceeded in any given year. For MCWD regulatory purposes, the rainfall depths to be used are as specified in the current NOAA guidance, “NOAA Atlas 14 Precipitation Frequency Estimates.” All rainfall depths are to use the NRCS MSE-3 rainfall distribution.
• Development means a land-disturbing activity, other than a Linear Transportation Project, that creates or reconstructs impervious surface.
• Dredge means to remove sediment or other material from the bed, bank or shore of a waterbody by means of hydraulic suction, mechanical excavation or any other means.
• Excavation means to displace or remove sediment or other material.
• Fast Track Permit means a permit for activity that typically presents low risk to water resources and is issued by staff without public notice and on the basis of more limited application submittals. 
• Fill means a solid material, other than stockpiled temporarily for active use, that alters the cross-section of a waterbody bed or bank, floodplain, or buffer area. For the purpose of the Wetland Protection Rule, “fill” also includes a material as defined at Minnesota Rules 8420.0111, subpart 26.
• Floodplain means the area adjoining a watercourse or water basin that is covered by the Regional Flood.
• General Permit means a permit that is deemed issued to an applicant on the applicant’s notice to the District and submittal of an abbreviated set of application materials.
• Impervious means compacted or covered with a layer of material so as to be highly resistant to infiltration of runoff, including but not limited to gravel, rock, asphalt, pavers, and concrete. Surface materials (asphalt, concrete, pavers) designed to infiltrate stormwater, artificial turf, and playground surfacing are considered to be impervious.
• Land-disturbing activity or land disturbance means a disturbance of the ground surface that exposes soil and, through the action of wind or water, may result in soil erosion or the movement of sediment into waters, wetlands or storm sewers or onto adjacent property. Land-disturbing activity includes but is not limited to the demolition of a structure that exposes the surface, soil stripping, clearing, grubbing, grading, excavating, filling, but does not include agricultural activity.  
• Linear Transportation Project means construction of a new road, trail, or sidewalk or reconstruction of an existing road, trail, or sidewalk.
• Management Class meansa wetland designation set forth in the MCWD’s Functional Assessment of Wetlands based on the ecological function and vulnerability of the wetland. In order of highest function and vulnerability, management classes are Preserve, Manage 1, Manage 2 and Manage 3.
• Meadow Condition is a modeled event that uses concentration of 0.04 mg/L of Total Phosphorus in runoff in accordance with the Minnesota Pollution Control Agency’s Minnesota Stormwater Manual and the MCWD Hydrologic, Hydraulic, and Pollutant Loading Study (HHPLS). For runoff rates, meadow condition uses curve numbers corresponding to soil and cover types “meadow,” “brush,” or “woods,” as appropriate, provided in Table 2-2c of the Natural Resources Conservation Service’s (NRCS) Technical Release 55 (TR-55).
• Native Vegetation means plant species that are indigenous to Minnesota or that expand the range into Minnesota without being intentionally or unintentionally introduced by human activity, and that are classified as native in the Minnesota Plant Encyclopedia, Minnesota Department of Natural Resources, St. Paul, 2002.
• New Principal Residential Structure means a single-family residence constructed on an undeveloped lot of record zoned for residential use, or on a lot of record zoned for residential use from which the principal building has been removed to construct a new single-family residence. The term does not apply to a lot of record created by subdivision subject to the vegetated buffer requirement of the Wetland Protection Rule.
• No-Rise Standard means demonstration that the increase in 100-year high water level is no more than 0.00 ft from existing to proposed condition.
• No-Rise Certificate means the “No Rise” certification provided by the Minnesota Department of Natural Resources
• NPDES means the “National Pollutant Discharge Elimination System” program under the federal Clean Water Act.
• NURP means Nationwide Urban Runoff Program, as developed by the U.S. Environmental Protection Agency (EPA) to study stormwater runoff from urban development.
• 100-year high water elevation means the water elevation reached by the Regional Flood, as determined by, in the order of preference, the most recent municipal, District or FEMA modeling, or by the applicant, in each case subject to the District’s concurrence as to modeling adequacy.
• Ordinary high water level (OHW) is the elevation of a waterbody that is the highest water level that has existed for a sufficient time to leave evidence on the landscape. It is commonly the elevation where the natural vegetation changes from predominantly aquatic to predominantly terrestrial. For a watercourse, the OHW is the elevation of the channel top of bank. For a reservoir or flowage, the OHW is the operating elevation of the normal summer pool.
• Person means a natural person, partnership, unincorporated association, corporation, municipal corporation or political subdivision of the State of Minnesota.
• Pervious means readily penetrated or permeated by rainfall or runoff resulting in infiltration and reduced runoff.
• Point source means a discrete point of discharge to water, such as a pipe or ditch.
• Public water means a water as defined under Minn. Stat.103G.005, subd. 15.
• Public waters wetland means a wetland defined under Minn. Stat. 103G.005, subd. 18.
• Reconstructed meansthat impervious surface has been removed to underlying soil. Activities such as structure renovation, mill and overlay, and other pavement rehabilitation that do not expose underlying soil beneath the structure, pavement, or activity are not considered as reconstructed. Limited impervious surface replacement associated with maintenance activity such as catch basin repair/replacement, utility repair/replacement, pipe repair/replacement, lighting installation, or pedestrian ramp improvement is not considered to be reconstructed surface.
• Regional flood means the precipitation event, associated with the location, expected to occur with an average frequency of once each 100 years, and the volume and intensity of precipitation associated with that event, as set forth in the regional precipitation data set adopted and maintained by the District.
• Residential appurtenance means (a) a driveway, or (b) a structure or surface that throughout the watershed customarily is associated with residential use of a property, and that does not exceed 5,000 square feet of impervious surface.
• Site means a parcel or contiguous parcels of record on which activity subject to a District rule is proposed to occur, as well as any tract contiguous thereto under common ownership. For a Linear Transportation Project within right-of-way that is not of record, the Site is bounded by the longitudinal termini of the proposed activity but includes area outside of the right-of-way designated by the applicant for project purposes.
• Stabilization Zone means an area of land parallel to a shoreline or streambank and extending 20 feet inland from the ordinary high-water level.
• Stabilize means to establish a surface condition that, without maintenance, will not be subject to soil erosion or sediment movement.
• Structural Practice is the use of an engineered system – such as riprap, retaining wall, headwall, groin, revetment or gabion – to stabilize a shoreline or streambank area and associated slope.
• Subwatershed means one of the fifteen major subwatershed planning units within the District, as identified in the District’s watershed management plan.
• Top of bank means the ordinary high water level for a water basin or wetland, and the break in slope for a watercourse.
• Volume reduction means permanent retention of runoff on a site through structures and practices such as infiltration, evapotranspiration and capture and reuse. See also the Volume Reduction Credit Schedule in Appendix A of the Stormwater Management Rule.
• Waterbasin means an enclosed natural depression with definable banks, capable of containing water, that may be partly filled with water.
• Waterbody means a waterbasin, watercourse or wetland as defined in these rules.
• Watercourse means a channel with definable beds and banks capable of conducting generally confined runoff from adjacent lands. A watercourse may be perennial or intermittent. The term does not include a roadside ditch created by excavation or other human construction activity.
• Wetland means a feature identified as a wetland under Minn. Stat. 103G.005, subd 19. The term does not include “public waters wetlands” as defined under Minn. Stat. 103G.005, subd. 15a.