Memorandum <br />Page 1 <br />800 Willamette Street, Suite 400, Eugene, OR 97401 541.684.4902 FAX 541.684.4909 <br />Eugene, OR Portland, OR <br />DATE:March 5, 2024 <br />PROJECT:2100216-Braewood Hills PUD SUBJECT:Storm Drainage <br />TO:Carol Schirmer FROM:Anna Backus, PE <br />Schirmer Consulting, LLC KPFF Consulting Engineers <br />PHONE:541.234.5108 PHONE:541.684.4902 <br />EMAIL:schirmer@schirmerconsulting.com EMAIL:anna.backus@kpff.com <br />This memo has been prepared to show that the proposed Braewood Hills PUD meets the requirements of <br />the City of Eugene Stormwater Management Manual and Eugene City Code, including stormwater quality, <br />flood control, flow control, oil control and source control.Due to wetlands on the site,it must meet NOAA’s <br />Standard Local Operating Procedures for Endangered Species V (SLOPES V), which has stricter requirements <br />for stormwater. <br />Existing Conditions <br />The site is located east of Hawkins Lane, north of Randy Lane and west of Suncrest Drive. The existing <br />conditions include a partially cleared hillside with a combination of trees, ground cover and low brush. The <br />soil on site includes several types of silty clay loams all rated as Hydrologic Soil Group D. This means that the <br />soil has a very slow infiltration rate when wet. <br />There are no storm facilities on site, but there is a 12-inch main in Randy Lane at the southwest corner of the <br />proposed development area.There is another 12-inch main that crosses Hawkins Lane at the northwest <br />corner. Both of these mains outfall on the west side of Hawkins Lane into Videra Creek.Videra Creek is part <br />of the Amazon Creek drainage basin, as defined in the 2002 City of Eugene Stormwater Basin Master Plan. <br />Proposed Conditions <br />The proposed conditions include two private drives, utilities to serve the PUD and vegetated stormwater <br />facilities. Additionally, the neighborhood on the uphill side of the development to the east has a storm outfall <br />that drains into the proposed PUD. The existing pipe outfall feeds a wetland that will be protected. The runoff <br />will be collected where the water becomes channelized at the low end of the wetland.The water inflow to <br />protected wetlands will not be impacted. The water flow through the site will be managed so that the overall <br />runoff from the site is not increased due to the development. Because the downstream system will not be <br />impacted by the development, a downstream analysis has not been included. See the Flood Control section. <br />Stormwater quality (vegetated treatment)for each lot will be addressed by the individual home builder at <br />the time of construction. <br />2025 <br />2024.07.02 <br />14:35:59-07'00'