(A) All excavations, grading, or filling shall have a finished grade not to exceed a 3:1 slope (33%). Steeper grades may be approved if the excavation is through rock or the excavation or the fill is adequately protected (a designed head wall or toe wall may be required). Retaining walls that exceed a height of four feet shall require the construction of safety guards as identified in the appropriate section(s) of the adopted BOCA Codes and must be approved by the City Building Department. Permanent safety guards will be constructed in accordance with the appropriate section(s) of the adopted BOCA Codes.
(B) Sediment and erosion control plans for sites that exceed one acre of grading shall provide for sediment or debris basins, silt traps or filters, staked straw bales or other approved measures to remove sediment from run-off waters. Temporary siltation control measures shall be maintained until vegetative cover is established at a sufficient density to provide erosion control on the site.
(1) All lots less than one acre that are currently being constructed upon as commercial or residential may be required to take action to control silt run off to public right-of-way or private adjacent property as determined by the building and zoning inspectors. Failure to install appropriate siltation barriers to ease silt run off may result in stop work orders until corrective action is taken.
(2) In addition, excessive siltation run off from construction sites onto public streets will be cleaned by those responsible. If not cleaned at the end of any work day, the city may have the street cleaned and the owner will bear the costs associated with this work.
(C) (1) Where natural vegetation is removed during grading, vegetation shall be re-established in such a density as to prevent erosion. Permanent type grasses shall be established as soon as possible or during the next seeding period after grading has been completed. When grading operations are completed or suspended for more than 30 days, temporary grass must be established at sufficient density to provide erosion control on the site. Between permanent grass seeding periods, temporary cover shall be provided according to the designated officials’ recommendation.
(2) All finished grades (areas not to be disturbed by future improvement) in excess of 20% slopes (5:1) shall be mulched and tacked at the rate of 100 pounds per 1,000 square feet when seeded.
(D) (1) Provisions shall be made to accommodate the increased runoff caused by changed soil and surface conditions during and after grading. Unvegetated open channels shall be designed so that gradients result in velocities of two fps (feet per second) or less.
(2) Open channels with velocities more than two fps and less than five fps shall be established in permanent vegetation by use of commercial erosion control blankets or lined with rock rip rap or concrete or other suitable materials as approved. Detention basins, diversions, or other appropriate structures shall be constructed to prevent velocities above five fps.
(E) The adjoining ground to development sites (lots) shall be provided with protection from accelerated and increased surface water, silt from erosion, and any other consequences of erosion. Run-off water from developed areas (parking lots, paved sites, and buildings) above the area to be developed shall be directed to diversions, detention basins, concrete gutters, and/or underground outlet systems. Sufficiently anchored straw bales may be accepted as a temporary substitute.
(F) Development along natural watercourses shall have residential, commercial or industrial improvements, parking areas or driveways setback a minimum of 25 feet from the top of the existing stream bank. The watercourse shall be maintained and made the responsibility of the subdivision trustees or in the case of a site plan by the property owner. Permanent vegetation should be left intact. Variances will include designed streambank erosion control measures and must be approved.
(G) FEMA and U.S. Army Corps of Engineers guidelines shall be followed where applicable regarding site development areas designated as flood plains and wetlands.
(H) All lots shall be seeded and mulched at the rate of 200 pounds/acre or sodded before an occupancy permit shall be issued except that a temporary occupancy permit may be issued by the Building and Zoning Department in cases of undue hardship because of unfavorable ground conditions.
(Prior Code, § 156.03) (Ord. 99-13, passed 9-7-1999)