CC PACKET 11101998 - Laserfiche WebLink

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• Subd. 5. Drain inlet protection. All storm drain inlets shall be protected during construction until control measures are in place with a straw bale, silt fence or equivalent barrier meeting accepted design criteria, standards and specifications contained in the MPCA publication "Protecting Water Quality in Urban Areas". Subd. 6. Site erosion control.- The requirements of this subdivision apply only to construction activities that result in runoff leaving the site. (a) Channelized runoff from adjacent areas passing through the site shall be diverted around disturbed areas, if practical. Otherwise,the channel shall be protected as described below. Sheetflow runoff from adjacent areas greater than 10,000 square feet in area shall also be diverted around disturbed areas, unless shown to have resultant runoff velocity of less than 0.5 ft./sec. across the disturbed area for the one year storm. Diverted runoff shall be conveyed in a manner that will not erode . the conveyance and receiving channels. (b) All activities on the site shall be conducted in a logical sequence to minimize the area of bare soil exposed at any one time. (c) Runoff from the entire disturbed area on the site shall be controlled by meeting either subsections 1 and 2 or 1 and 3. • (1) All disturbed ground left inactive for 14 or.more days shall be stabilized by seeding or sodding (only available prior to September 15) or by mulching or covering or other equivalent control measure. (2) For sites with more than 10 acres disturbed at one time, or if a channel originates in the disturbed area, one or more temporary or permanent sedimentation basins shall be constructed. Each sedimentation basin shall have a surface area of at least I% of the area draining to the basin and at least three feet of depth and constructed in accordance with accepted design specifications. Sediment shall be removed to maintain a depth of three feet. The basin discharge rate shall also be sufficiently low as to not cause erosion along the discharge channel or the receiving water. (3) For sites with less than 10 acres disturbed at one time, silt fences, straw bales; or equivalent control measure shall be placed along all side slope and downslope sides of the site. If a channel or area of concentrated runoff passes through the site, silt fences shall be placed along the channel edges to reduce sediment reaching the channel. The use of silt fences, straw bales, or equivalent control measure must include a maintenance and inspection schedule.