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Page: 3 <br /> <br /> <br /> <br />STORMWATER MANAGEMENT <br />1. The proposed subdivision is subject to a Stormwater Management Plan (SWMP) meeting State, <br />South Washington Watershed District (SWWD) and City rules. A SWWD permit is required. <br />2. The Preliminary Plat/Plans propose improvements that reside within the larger Inwood <br />subdivision in which stormwater management provisions have been previously designed, <br />permitted and constructed. <br />3. The allowable maximum impervious surface for each Lot has been documented on the Preliminary <br />Stormwater Management Plan and is consistent with the approved Inwood Stormwater <br />Management Plan. As final construction plans are prepared for the Subdivision, and future lot <br />build-outs, the impervious surfaces must remain below the maximum allowable, and the <br />stormwater drainage systems must be designed to direct runoff to the allocated stormwater <br />management basin. <br />4. The site design will create a maximum of 5.561 acres of new impervious surface once all public <br />improvements and all 5 lots have developed. A maximum of 3.184 acres of new impervious <br />surface will be conveyed and managed through Pond 200 (located east of the site) while a <br />maximum of 2.377 acres of new impervious surface will be conveyed and managed through Pond <br />100 (located on the south side of 5th Street). <br /> The SWMP must be revised to add an exhibit that clearly presents the impervious surface <br />limits for each lot, including impervious surface allowed for each lot within the shoreland <br />district boundary and the impervious surface allowed for each lot outside of the shoreland <br />district boundary. The exhibit must also label and call-out the required storm sewer <br />connection location for each lot together with a delineated drainage shed that is allowed <br />to drain to each connection location. Lot labeling must be consistent with the proposed <br />preliminary and final plat. <br /> The SWMP must be revised to account for and address the new impervious surfaces <br />created within the County right-of-way and bituminous trails. <br /> The Grading Plans and SWMP must be revised to account for the bituminous trail <br />construction along Inwood Avenue and 10th Street and the drainage limits must be clearly <br />identified for the areas allowed to drain to County right-of-way. <br />2. Approval of the Preliminary Plat/Plans for the development is contingent upon all SWMP revisions, <br />as required by the SWWD or other applicable permitting agency, being submitted to the City for <br />review and approval. <br />3. Approval of the preliminary grading and storm sewer plans for the development is contingent upon <br />all grading plans being reviewed and approved by the City Engineer prior to the start of any grading <br />or construction. <br /> The grading plans must include lot corner and lot line spot elevations to clearly define <br />limits of the public right-of-way improvements and tie-in elevations for future lot grading <br />activities. <br /> Overland emergency overflow (EOF) elevations are required throughout the site at all <br />localized low points. Low openings for adjacent structures must maintain 1-foot above <br />any adjacent EOF in the as-built condition. <br /> The grading plans must include minimum low floor and/or low opening elevations for <br />each lot based on the SWMP and emergency overflow elevations. <br /> The storm sewer plans must be revised to eliminate the 21-inch storm sewer stub being <br />extended to Lot 2, Block 2 as runoff from this area to Pond 200 is inconsistent with the <br />proposed SWMP. Connections to existing storm sewer stubs along 5th Street must be <br />called out for use by this Lot and the downstream storm sewer system capacity must be <br />modeled and verified. <br />4. Plan revisions may be required to meet City design standards and to mitigate encroachments.