(A) The following Best Management Practices which address the problem of urban runoff shall apply to all projects undergoing construction in the city. The Best Management Practices list set forth below is required by the city. The requirements set forth below shall apply at the time of demolition of an existing structure or commencement of construction and until receipt of a certificate of occupancy:
(1) Runoff sediment and construction waste from construction sites and parking areas shall not leave the site;
(2) Any sediments or other materials which are tracked off the site shall be removed the same day as they are tracked off the site. Where determined by the Stormwater Manager or his or her designated representative, a temporary sediment barrier shall be installed;
(3) On an emergency basis only, plastic covering may be utilized to prevent erosion of an otherwise unprotected area, along with runoff devices to intercept and safely convey the runoff;
(4) Excavated soil shall be located on the site in a manner that eliminates the possibility of sediments running into the street or adjoining properties. Soil piles shall be covered until the soil is either used or removed. A plastic or micro-mesh fabric should be used;
(5) No washing of construction or other industrial vehicles shall be allowed adjacent to a construction site. No runoff from wash vehicles on a construction site is allowed to leave the site;
(6) Drainage controls shall be utilized as needed, depending on the extent of proposed grading and topography of the site, including but not limited to the following:
(a) Detention ponds, sediment ponds or infiltration pits;
(b) Dikes, filter berms, silt fences or ditches;
(c) Down drains, chutes or flumes.
(B) Observe basic principles such as:
(1) Preserve existing vegetation as much as possible;
(2) Mulch or seed bare soil immediately for the best and cheapest erosion protection;
(3) Use silt fences, brush barriers, or other approaches to pond and filter sediment from runoff;
(4) Install silt check dams made of rock, brush or other products to prevent ditch erosion and remove sediment;
(5) Protect inlets and outlets; and
(6) Settle out soil particles in sediment traps and basins.
(C) The Stormwater Management Plan shall contain, but not be limited to, the following information unless specifically excluded by the Stormwater Manager.
(1) A topographic map of the project site and adjacent areas, of suitable scale and contour interval, which shall define the location of streams, the extent of flood plains and calculated high water elevations, the shoreline of lakes, ponds, swamps and detention basins including their inflow and outflow structures, if any.
(2) The location and flow line elevation of all existing sanitary, storm or combined sewers.
(3) Detailed determination of runoff anticipated for the entire project site following development indicating design volumes and rates of proposed runoff for each portion of the watershed tributary to the storm drainage system, the calculations used to determine said runoff volumes and rates and restatement of the criteria which have been used by the project engineer throughout calculations.
(4) A layout of the proposed stormwater management system including the location and size of all drainage structures, storm sewers, channels and channel sections, detention basins, and analyses regarding the effect said improvements will have upon the receiving channel and its high water elevation.
(5) The slope, type, and size of all existing and proposed storm sewers and other waterways impacting or impacted by the proposed development on the site.
(6) For all detention basins, a plot of tabulation of storage volumes with corresponding water surface elevations and of the basin outflow rates for those water surface elevations
(7) For all detention basins, design hydrographs of inflow and outflow for the 25 year, 24-hour events for the site under existing and developed conditions.
(8) A profile and one or more cross sections of all existing and proposed channels or other open drainage facilities, showing existing conditions and the proposed changes thereto, conditions called for by these regulations and the relationship of structures, streets and other utilities to such channels.
(Ord. 2803, passed 12-10-2012) Penalty, see § 160.99