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A. Definitions: The definitions set out in subsection 9-13-4P1 of this Code are hereby incorporated in this subsection by reference.
B. Erosion And Silt Control Plan: No person shall engage in any land disturbing activity, without first providing and then implementing and following an erosion and silt control plan compliant with this section. This plan is required before a construction permit shall be issued. The erosion and silt control plan shall comply with the following directives:
1. Nature Of Work: The plan must describe the nature and extent of the work.
2. Silt Screen Fence: A silt screen fence shall be installed below the direction of runoff in a manner so as to be most effective in preventing siltation of soil onto downstream adjacent properties, streets or into a public lake or storm sewer.
The silt screen fence shall be installed to run a sufficient length of the land disturbing activity and be blocked on each end to prevent runoff around the ends of the fence in order to protect the adjacent properties, streets, public waters or storm sewer from siltation from the entire land disturbing activity area. Silt fence should normally be spaced so that not more than one-fourth (1/4) acre of land drains into one hundred feet (100') of silt fence run. The bottom edge of a silt fence should equal the top elevation of the next fence downstream, especially when the slope is steep or the flows are concentrated. The spacing of silt fence on a slope should never be more than one hundred feet (100') to keep drainage areas to one-fourth (1/4) acre per one hundred foot (100') of run.
The silt screen shall have a minimum width of twenty four inches (24") and be installed in such a manner so that the bottom of the screen is tucked into the surface of the lot a minimum of six inches (6") by digging a narrow slit and simultaneously tucking the fabric into the ground and compacting the silt, thus reducing the chance of piping under the fence.
The silt screen fence support posts shall be spaced along the entire length of the fence with a maximum distance of eight feet (8') between the posts. Said posts shall extend above the silt screen and be placed into the ground at a depth consistent with their design and to provide adequate support of the silt screen.
Silt screening shall also be constructed around any storm sewer or drain intakes that could receive dirt or silt from the land disturbing activity.
3. Alternative Methods Of Erosion Control: An alternative solution to erosion control and siltation management may be proposed to the zoning officer such as the use of compost blankets. Approved erosion control methods as defined in the Iowa DNR erosion control manuals (including "Construction Site Erosion Control Manual" and "How To Control Streambank Erosion") or the "Iowa Stormwater Management Manual" may be used if erosion is kept to acceptable levels and sediment is contained on site. In addition, section 402 of the U.S. Clean Water Act, which contains the national pollutant discharge elimination system (NPDES) regulations, should be considered.
4. Duration: The silt screen fence or alternative method of erosion control shall be installed before any land disturbing activity begins, and shall remain in place and be maintained until all land disturbing activity is completed and sufficient landscaping or vegetation stabilization exists to prevent runoff. National pollutant discharge elimination system (NPDES) considers the site stabilized when seventy percent (70%) of the soil surface is vegetated.
Before the silt screen fence or alternate method of erosion control is permanently removed, all collected silt at the base of the fencing must be removed and distributed on the site or disposed of at a site that poses no continued threat of siltation.
5. NPDES Permit Required: With a development of one (1) acre or more, the City shall be provided a copy of the NPDES permit before approval of a plat can be made.
6. Construction Of Vehicle Exit: Removal of soil, silt and debris from construction sites shall also be limited by the construction and maintenance during the duration of the project of a rock or gravel vehicle exit to the site which shall be of sufficient length and area to significantly limit the amount of soil, silt and debris carried from the site on the tires of vehicles exiting the site.
C. Violation: Violations of this section constitute a simple misdemeanor. Each day such violation continues shall be deemed a separate offense. (Ord. 733, 11-21-2011)