1710 W MARINE VIEW DR 2024-01-03

The comments below were generated from this project's City of Everett Stormwater Reviewers. All questions shall be routed through this project's Public Works Reviewer with City of Everett Permit Services. # Document Sht/Pg Reviewer's Comment Designer's Response Initials 1 SSP Backwater Include a labels for the lettered pipes in the downstream Noted - labels are included in Appendix C. CWC Calculations map. 2 SSP MGS What do the structures "outfall" and "Null" represent? "NULL" Is a modeling placeholder for the CWC Calculations These are large structures, but I'm not sure how they pre -developed condition to represent the impact the stormwater design. proposed stormwater treatment vault. In the post -developed condition, "NULL" is replaced with "TREATMENT" 3 SSP Is there any concern that very high tides/storm surge will A tideflex checkmate check valve will be CWC impact trees with salt water? Record high tide is well above added downstream of the treatment vault. the outlet IE of the Filterra device. Include a backwater valve or ensure (with note on plans) that the selected tree species is tolerant of occasional saltwater inundation. (Downstream analysis did not indicate a tidegate at outfall. If there is one this comment can be ignored.) 4 SSP WQ sizing Please connect the dots from design WQ flow rate to facility Noted - Section 7.6 of the stormwater CWC sizing. I was not able to locate a description of the required report has been revised to verify the oil treatment footprint or facility capacity other than a control design sizing rate. statement that the treatment vault flow rate is 0.069 CFS in the text. There is no way to verify that the oil control design rate was used, etc. A sizing letter from the manufacturer is also acceptable as long as it states the design assumptions. 5 Plans C3.01 Existing CB in SE corner of site is noted to be raised to The catch basin and associated pipe will CWC grade and solid lid. Why not remove as this does not be difficult to demolish as there are a appear to be junction or serve any purpose. number of active existing utilities in close proximity on either side of the structure and around the existing pipe. Page 2 of 3