Laserfiche WebLink
SAGE HOMES NORTHWEST, LLC <br />HARBORS EDGE DRAINAGE REPORT <br />AUGUST 2022 <br />4.5 CONVEYANCE <br />This project has evaluated the conveyance system of this project using the rational method (100-year <br />24-hr design storm) to ensure that a 100year storm even can be contained within the proposed <br />drainage network without surcharging the proposed structures. Since this is a small site the minimum <br />time of concentration of 5 minutes has been used. The storm system layout was imported into <br />Hydraflow Storm Sewers software, an Autodesk extension that models backwater analysis. The <br />known flows (from the rational method) were entered into each catch basin, and the flows <br />accumulate down the system. Results are shown in Appendix F. The results show that the grade line <br />is calculated to be at or below the rim in each structure; therefore, the system has capacity for the <br />100-year flow. <br />PACE PAGE 18 IOU <br />