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watercourse that have been or hereafter may be covered by the regional flood.
<br />High water level is the expected elevation the water in a stormwater pond will rise to a 100 year rain event as
<br />calculated by the pond design.
<br />Hydric soils are soils that are saturated, flooded, or ponded long enough during the growing season to develop
<br />anaerobic conditions in the upper soil horizon.
<br />Hydrologic Soil Group (HSG) means a Natural Resource Conservation Service classification system in which
<br />soils are categorized into four runoff potential groups. The groups range from A soils, with high permeability
<br />and little runoff production, to D soils, which have low permeability rates and produce much more runoff.
<br />Impaired Waters are water bodies that do not meet water quality standards and designated uses because of
<br />pollutant(s), pollution, or unknown causes of impairment.
<br />Impervious surface is a constructed hard surface that either prevents or retards the entry of water into the soil
<br />and causes water to run off the surface in greater quantities and at an increased rate of flow than existed prior to
<br />development. Examples include rooftops, sidewalks, patios, driveways, parking lots, storage areas, and
<br />concrete, asphalt, or gravel roads. Class 5 gravel surfaces are considered to be impervious surfaces.
<br />Land disturbance activity is any land change that may result in soil erosion from water or wind and the
<br />movement of sediments into or upon waters or lands within this governmentÓs jurisdiction, including but not
<br />limited to construction, clearing and grubbing, grading, excavating, transporting and filling of land. Within the
<br />context of this ordinance, land disturbance activity does not mean:
<br />(A)minor land disturbance activities including, but not limited to, underground utility repairs, home
<br />gardens, home landscaping, minor repairs and maintenance work which do not disturb more than two thousand
<br />(2,000) square feet of land or exceed one hundred (100) cubic yards of earthwork provided work does not
<br />obstruct or modify a watercourse or storm sewer system and is not located in a floodplain;
<br />(B)installation and maintenance of fences, signs, posts, poles, electric, telephone, cable television, utility
<br />lines or individual service connections to these utilities; or
<br />(C)general farming practices, or
<br />(D)emergency work to protect life, limb, or property and emergency repairs, unless the land disturbing
<br />activity would have otherwise required an approved erosion and sediment control plan, except for the
<br />emergency. If such a plan would have been required, then the disturbed land area shall be shaped and stabilized
<br />in accordance with the cityÓs requirements as soon as possible.
<br />Native vegetation is the pre-settlement (already existing in Minnesota at the time of statehood in 1858) group of
<br />plant species native to the local region, that were not introduced as a result of European settlement or
<br />subsequent human introduction.
<br />Normal water level refers to the permanent pool of water retained in a stormwater
<br />pond. By design, this is the water level below the invert elevation of the pond outlet with a depth not to exceed
<br />eight (8) feet.
<br />Ordinary high water level "Ordinary high water level" means the boundary of water basins, watercourses,
<br />public waters, and public waters wetlands, and:
<br />(A)the ordinary high water level is an elevation delineating the highest water level that has been
<br />maintained for a sufficient period of time to leave evidence upon the landscape, commonly the point where the
<br />natural vegetation changes from predominantly aquatic to predominantly terrestrial;
<br />(B)for watercourses, the ordinary high water level is the elevation of the top of the bank of the channel;
<br />and
<br />(C)for reservoirs and flowages, the ordinary high water level is the operating elevation of the normal
<br />summer pool.
<br />Outfall is the point of discharge to any watercourse from a public or private stormwater drainage system.
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