6400 MERRILL CREEK PKY 2018-01-01 MF Import

i � � r�ar� aavz�r coria.E a �etuon� , City standards require a length to width ratio of 3: 1 for � watponds. Solid baffles can be usad to create an effective i lenqth to width ratio equal to or greater than 3:1. City � standards also call for at least one baffle across the width � of the pond. Baffles used to create an effective le�qth to width ratio of 3 :1 are required to extend vertically from the bottom of the pond to the elevation correlating to storage of the wetpond design volume, the required baffle oss the width of the pond is requirad to extend to the acr s ma dead storage elevation. Earthen berms or concrete wall y � be used as baffles. 1f A planting schedule for the treatment area of the wetpond is i required for approval by the City. The plans should call out the type of vegetation to be planted, the density of the plantings, and the total number of plants needed. wetland emergent plants suited to the depth of water in the treatment areas should be used. Hardstem bulrush, yellow iris, and/or cattails are appropriate in areas of the pond ;I with 1-2 feet of water, with small fruited bulrush, spike ' rush and/or soft rush planted around the wetland treat►uent i cell perimeter. Required density of plantings is a minimum of one per 2.25 square feet (1.5' o.C. ) . � The pond detail needs to clearly show the area of the pond l to be planted and a note should reference the planting schedule. The note should also indicate plantir�g of the � required vegetation in groups, rather than in a completely j random pattPrn. The actual contours for the pond and how they relate to the surrounding topoqraphy should be shown. Wetpond side slopes may not be steeper than 3:1 (H:V) unlesa retaining walls are provided. Rockeries are generally not allowed in conjunction with wetponds, unless the rockeries are set well back from the high water level in the pond. Unless a wetvault is provided instead of the open water cell, City standards require a 72 inch diameter catch basin/manhole, with a 48 inch deep sump, to be provided upstream of the wetpond to provide for grit removal. Access to the open water cell of the wetpond, if a wetvault is not provided, is required as detailed in �ection 4-6.3 of the City�� Design and Construction Standards and Specifications. Rip-rap 12" deep and 2' wide should be placed from the inlet to the pond to the bottom of the pond.