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<br />placed below the 100-year high-water level for the placement of the northern driveway; therefore, the <br />rule is triggered. To meet MCWD’ Floodplain Alteration rule requirements, please address the following <br />items: <br />• Determine the OHW and 100-year elevations for the tributary driveway crossing. <br />• Existing conditions site plan: <br />o Existing elevation contours of the work area <br />o Ordinary high-water elevation (OHW) <br />o 100-year flood elevation <br />• Proposed site plan: <br />o Proposed elevation contours of the work area <br />o Ordinary high-water elevation (OHW) <br />o 100-year flood elevation <br />• Calculation of cut and fill: <br />o Quantity of proposed cut and fill corresponding to areas of cut and fill on the site plans <br />(no net fill is allowed) <br />o Sum of proposed cut and fill between OHW and 100-year flood elevation <br />o Calculations must be signed by a professional engineer, architect, land surveyor, or <br />landscape architect <br /> <br />Waterbody Crossings and Structures: <br />MCWD’s Waterbody Crossings and Structures Rule is triggered when work is proposed within the bed or <br />bank of a waterbody. This rule requires that the proposed work maintains hydraulic capacity, <br />navigational capacity, and wildlife passage, and has no adverse impacts to water quality. To meet <br />MCWD’s Waterbody Crossings & Structures rule requirements, please address the following items: <br />o Please clarify the existing and proposed conditions for the connection between Wetland <br />1 and Wetland 2. This includes hydraulic capacity (i.e. peak flows) in existing and <br />proposed conditions as well as upstream and downstream high water levels in existing <br />and proposed conditions <br /> Note, high water levels can be determined from the high water levels of <br />Wetland 1 and Wetland 2. <br /> Provide the diameter, material, inverts, and lengths of the connection in the <br />existing and proposed conditions. <br />o Delineate full drainage area of Wetland 1 so that culverts can be sized appropriately. <br />Culverts must retain adequate hydraulic capacity. A project in a watercourse may not <br />increase upstream or downstream flood stage. <br />o Please provide documentation that the wetland/waterbody crossing is the “minimal <br />impact” solution to the specific need. Please provide at least two alternative designs <br />that minimize or avoid the proposed impact to demonstrate that the minimal impact <br />solution is proposed. Additionally, please provide an analysis, by a professional engineer <br />or qualified hydrologist, of the effect of the project on hydraulic capacity and water <br />quality. <br /> <br />Wetland Protection Rule <br />155