Laserfiche WebLink
• <br />John Powell Page 2 May 1, 2001 <br />Spirit Hills <br />Drainage <br />1. In the HydroCAD model, all Times of Concentration were "Direct Entry ". Time of <br />Concentration computations still need to be submitted. <br />2. The 2- and 100 -year storm events were submitted. The City requires rate control for the <br />1 -, 10 -, and 100 -year storm events. Please submit the 1- and 10 -year events. <br />3. The City Surface Water Plan does not allow for dry basins. All basins must be designed <br />to wet NURP basin standards: <br />2.5" dead storage volume <br />4:1 side slopes max. <br />15 feet of 10:1 bench at normal water level <br />4 feet minimum depth on dead storage <br />3:1 length to width ratio <br />4. Storm sewer pipe sizes and slopes are needed on the plan sheets. <br />5. The storm sewer computations do not always match the plans. Please review and correct <br />• any discrepancies. <br />6. The minimum cover for catch basins and catch basin manholes is 4.0 feet from the rim to <br />the top of pipe, or 2.5 feet if draintile is installed. The location of the draintile as well as <br />the draintile detail must be included in the plans. <br />Miscellaneous <br />1. Copies of the final approvals from the Rice Creek Watershed District and the Anoka <br />County Highway Department will be needed for this project. <br />If you have any questions or comments regarding this review, please contact me. <br />