2201 EVERETT AVE SEPA 018 - 008 Drainage Report 2025-04-15

8. The downstream storm system will be protected by providing downspouts at roof locations and piped to the catch basins and pipe conveyance system. During construction CB protection will be provided at the existing downstream Catch Basins and new Catch Basins. 9. Standard construction notes will be added to the plans; there does not appear to be a problem with controlling pollutants; On-site pollutant management from construction activities will take place. 10. No dewatering issues are anticipated;however dewatering measures will take place as needed and directed by the Geotechnical Engineer. 11. Standard construction plans and erosion control notes will be added to the plan. These notes require maintaining the BMPs. 12. The project might be phased; seasonal work limitations or clearing/grading restrictions might be deemed necessary pending weather conditions. 13. Protect all Bioretention and Rain Garden BMPs from sedimentation through installation and maintenance of erosion and sediment control BMPs on portions of the site that drain into the Bioretention and/or Rain Garden BMPs. Restore the BMPs to their fully functioning condition if they accumulate sediment during construction. Restoring the BMP must include removal of sediment and any sediment-laden Bioretention/rain garden soils, and replacing the removed soils with soils meeting 2014 Stormwater Management Manual for Western Washington Volume II-Chapter 3 - Page 253 the design specification. Prevent compacting Bioretention and rain garden BMPs by excluding construction equipment and foot traffic. Protect completed lawn and landscaped areas from compaction due to construction equipment. Control erosion and avoid introducing sediment from surrounding land uses onto permeable pavements. Do not allow muddy construction equipment on the base material or pavement. Do not allow sediment-laden runoff onto permeable pavements. Pavements fouled with sediments or no longer passing an initial infiltration test must be cleaned using procedures from the local stormwater manual or the manufacturer's procedures. Keep all heavy equipment off existing soils under LID facilities that have been excavated to final grade to retain the infiltration rate of the soils. Note:Fo-Additional information See the Attached City of Everett Construction Erosion and Sedimentation Control Plan BMP items. Requirement#3-Source Control of Pollution This project is simple, straight forward and short in duration. Some phasing of the site may be required for scheduling of construction material availability. There are no pollutants on-site that water must not come in contact with,except for sedimentation due to soil erosion. The main source of stormwater will come into contact with the native soil. The protections are noted above.