332 SW EVERETT MALL WAY 2018-01-01 MF Import

�• • � � • — Frontier Bank proposes to relocate their facilides to a new site in the southeast quadrant of the intersection of 4th Avenue West and Everett Mall Way. During the predesign meeting with the City of Everett, City staff expressed their desires for drainage _ improvements from the proposed site to the existing wetland southeasterly of the site. All practical routes to the wedand aze across property offsite of the bank development. PROJECT OVERVIEW AND EXISTING CONDITIONS The proposed development of the Everett Mall Way branch of Fronder Bank site is -- located on a pazcel of approximately 1.78 acres in south Everett. It lies east of 4th Avenue West and just south of Everett Mall Way. (See Exhibit "A".) It is part of a 4.08 acre development previously proposed ro the Ciry of Everett. That development �, never was completed, however, the pazcels have been linked with a common access and traffic circulation along their eastern boundary. The existing site is heavily vegetated and lies with an approximate 3% easterly slope. �-� It appears that offsite drainage upstream of the project has been intercepted by the ,, wllecdon system of 4th Avenue West and diverted southerly azound the project site. There is litUe sign of well defined drainage courses within the project boundazy. The ,,., majority of existing runoff exits the site as sheet flow. '' The adjacent easterly property has a gradient of approximately 6%. A poorly developed channel lies just south of the existing trailer park and has a 12" culvert to '' allow access to the southern portion of the property. Towazd the easterly boundary of ,., the adjacent property the exisdng channel diverges and becomes even less defined. �-� During construction of the P.U.D. substation an attempt was made to intercept the � sheet flow and convey it away from the site. A series of catch basins and piping along '"� with an interceptor ditch was constructed at the west boundary of the substation, which ,_, convey the runoff to the existing wetland to the south. — Sketches of the exisdng channels are shown on Exhibits "B" and "C". Although development for the bank facility is only for the northerly 1.78 acres, the entire 4.08 acre parcel has already been proposed to the City of Everett for combined " development by a previous owner. Construcung drainage facilides for the new bank , site may be of a benefit to the enGre site if they could be acwmplished in such a manner as to allow access for all the runoff. This design proposes to construct a single -- biofiltration swale and above ground detendon pond to service the en6re 4.08 acres at anticipated build-out development. (See Exhibit "D".) �� Drainage Report FronderBank Page 1