5001 SOUND AVE 2022-05-13 - Laserfiche WebLink

MR #4: Preservation of Natural Drainage Systems Natural drainage patterns shall be maintained,and discharges from the project site shall occur at the natural location. This Minimum Requirement has two main components to achieve: 1) maintain the natural on-site drainage pattern and concentrated discharge location at the downstream property boundary, and 2) prevent erosion at and downstream of the discharge locations. This requirement includes maintaining or replacing systems which convey runoff accross the site from upstream areas. All outfalls require energy dissipation. G u Task 1: Document existing and proposed drainage patterns and discharges Check the boxes that apply below: e This site has existing drainage systems or outfalls.These items are shown on the Stormwater Site Plan provided in MR#1 and are to include:type,slope,dimensions, channel lining,direction of flow and buffer. e This project will not alter the existing drainage system in any way. If the existing outfall(s) show sign of erosion and scour,energy disipation measures will be installed or improved upon. Construction activity of any kind will not occur within at least 10 ft of the edge of the channelized flow,BMP C102: Buffer Zones will be implemented during the life of the project to include visible flagging or other demarcation technique. If this requirement is not met a Hydraulic Project Approval (HPA) may be required from the Washington Department of Fish and Wildlife. ❑ The site does not have any existing drainage systems or outfalls. Describe how stormwater will be discharged from the site without causing erosion and flooding downstream: ❑ The existing concentrated drainage system traversing the property will be impacted as part of this project and is shown on the stormwater site plan. Describe how your project impacts or changes the existing drainage systems as a result of your project and how you will address it: City of Everett Public Works Small Project Stormwater Site Plan Report-Dec 2019 15