220 OLYMPIC BLVD VA OUTPATIENT CLINIC 2023-02-09

I fitki r- -- _ PROPOSED BASINS . , , ' \ "'/7 1 105,741 SF (2.42 ACRES) , SOUTH BASIN: w , r ; 1 35,600 SF (0.81 ACRES) ' �, , '.. r .,; NORTH BASIN ' f r; ;1 Q 62,847 SF (1.44 ACRES) ►' _am__ IDISTURBED OLYMPIC BASIN: i m �t __ram-- o 2,928 SF (0.07 ACRES) �- j DISTURBED MUKILTEO AND ELM BASIN: 4,366 SF (0.10 ACRES) •' . r ,i ., , . _____„. _, 1 - MIAULTEE BOULEVARD IFigure 7: Proposed Basins Map South Basin: The south basin is being improved by means of a 2" grind and overlay only, which Iis exempt from flow control per the City of Everett. The new plus replaced hard surface areas being created in this sub-basin are the new MRI building roof, new sidewalk along the western side of building, and new sidewalk, curb, and gutter along the right-of-way, which are non- ' pollution generating. Water quality treatment is, therefore, not required. Runoff from the south basin will be captured by a series of catch basins, conveyed to the north, and routed to an I existing manhole that connects to the existing 24-inch culverted Dogwood Elm Creek. Runoff from the south basin will not be routed through the proposed detention vault, but will instead be treated as bypass area for vault sizing. I Mukilteo/Elm Basin: New sidewalk, curb and gutter, and a new landscape strip are proposed along sections of Mukilteo Boulevard and Elm Street. The proposed areas do not exceed the Ithresholds requiring flow control or water quality treatment. Drainage from these areas will continue to flow to the existing stormwater manhole on the southeast corner of the project site where it converges with the culverted Dogwood Elm Creek flowing under the project site. IRunoff from this basin will not be routed through the proposed detention vault, but will instead be treated as bypass area for vault sizing. I I NAVIX Everett VA Clinic— Everett, WA 19 I