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E 5. duration with return frequencies of I, 10 and 100 years in the subwatershed in which the site is located. (b) Natural existing low areas will be used, where feasible, for detention of runoff to comply with rate control criteria. Reservoir routing procedures and critical duration runoff events shall be used for design of detention areas and outlets. (»)-Wat erborne sedimentG sholl be provontad fironventering existing drainog eways to provent sediment transport off the site during and aft er oonotruotion. (c f) The proposed project shall not adversely affect water levels off the site during or after construction. fig) Runoff droining onto the site tributary to the project must be accommodated in the analyses and design of new stormwater management facilities. (e b) The volume of s4te runoff may not increase due to the project when the receiving area of said runoff is landlocked, and not capable of handling the increased volume of runoff. In addition, the applicant shall either own or have proper rights over the landlocked property to handle water from the development. Back-to-back 100-vear runoff events will be used to analyze holding capacity and freeboard for landlocked areas. (f ♦) All stormwater rate control facilities sholl be located above the projected 100-year flood elevation for the site and within drainage, utility and/or flowage easements to provide access and to prevent future alteration or encroachment. fg tl Water quantity control methods and facilities used or constructed pursuant to Stormwat er Nkmage ment-Plans under this rul? shall be in conformance with approved Municipal Stormwater .Vlanagement Plans. (n k) The outfall structures within wetlands and public wat ers and wetlands shal l inoerporat e a saili ng bas in, surge basin, energy disoipat er, plac ement of ungrouted-noturol-fook-fip rop-or other devices to minimize distufbonoe and erosion of natural shof»iin»ttn<t bed resuking from-peok discharg es shall incorporate designs to minimize erosion and scouring. (i 1) AH-new residential, commercial, industria l and institutional buildings and structures shall be constructed such that all have door and window openings are a minimum of two feet above the 100 year high water elevation of neorby surface wat erbodies, wetlands end stormwate r bas ins. WATER QUALITY REQUIREMENTS. (a c) Wet detention ba sins pond shall be required on site and designed for at least 50% phosphorus removal efTiciency in a ccordanc e with the Minnesota Pollution ControE Agency (MPCAl design recommendat ions published in sections i. 1- -1 through 4.15 (“Protecting Woter Quality in Urbon Areas 1991”), and its future revisions. These design criterio were developed bas ed upon the results of the Nat ionwide Urban Runoff Program (NURPK^^SEPAt 198^)r The applicant shall use the PondNet (or approved equivalent) model to determine removal efficiency of the pond, using a 2.5” rainfall. Total site ar ea and anycontributing off site tributary drainage area shall be used to calculate permanent pool volume. Structura l Pond outlets shall remove floatables from ponded Draft-April 29, 1998 12 J