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Ms. Rachel Juba September 1, 2022 Page 2 Stormwater Management 7. The stormwater water quality and rate control requirements are proposed to be met through the use of onsite permeable pavement. The storage below the permeable pavement is sized to meet the City's water quality and RCWD's rate control requirements. 8. The applicant is not able to meet the 0.1 cfs/ac rate control rule due to site constraints. The City's rule allows for this 0.1 cfs/ac rate control requirement to be waived if the site discharges to a water body with a large storage capacity, the volume discharged from the project site does not contribute to downstream flood peak and there are no downstream locations susceptible to flooding. This site has demonstrated compliance with those three criteria and is showing a decrease in rates for all storm events this is not anticipated to have a negative impact on Egg Lake or any downstream properties. Additionally, the discharge volume to Egg Lake is decreased in all storm events so Egg Lake's HWL will not increase due to this project. 9. The proposed stormwater management meets all RCWD requirements. 10. There is not a regulated floodplain elevation set by FEMA or RCWD for Egg Lake. 11. An operations and maintenance plan for the permeable pavement has been included in the stormwater management plan. A stormwater maintenance agreement will be required for the permeable pavement on the site. Wetlands 12. A Notice of Decision was issued on March 3, 2022, approving a no-loss for the project based on plan sets submitted on November 11, 2021. The decision approved the installation of pilings within the portion of wetland above the OHW that falls under the jurisdiction of the wetland conservation act(WCA). No filling, draining, or excavation within the wetland is approved. 13. A series of eight(8) conditions were applied to the WCA approval for a no-loss. 14. The plans show clearing and grubbing of trees, but this was not included in the plan set that accompanied the application on 11/15/21. A narrative describing how this work can be done within the context of the previously issued No-loss is required. 15. Bioroll is still shown in the wetland which would constitute fill if left in place. 16. A separate US Army Corps permit has been issued for this project. Conditions of that permit must be followed. 17. One of the conditions of the WCA issued no-loss was to provide an existing (pre- construction)vegetation survey. The 2022 growing season is almost over and this still needs to be submitted. Thank you for the opportunity to provide comments on this project. Additional comments may be necessary following the review of the responses to these. If you have any questions, please do not hesitate to contact me at 651-286-8463. Sincerely, W�SB_ f yam' Mark Erichson, PE City Engineer cc: Scott Anderson, Public Works Director(email only) Liz Finnegan, Senior Engineering Technician (email only)