10632 7TH AVE SE 2025-07-28 - Laserfiche WebLink

I Iimpacted by our development. Vehicle and pedestrian traffic will be maintained during the construction period. IThere is a large existing rock wall that encompasses most of the onsite frontage. This wall and fence will remain along 7th Ave. SE. This wall varies in height from 4-10' and acts as a retention wall between the property and 7th Ave. Directly west of the wall is a hill with some large trees and light undergrowth that encompasses the majority of the front yard for the existing house. I From the hill near the northeast corner of the property, the topography drops steadily at 6-10%to the western lot boundary line. The back yard of the house is mostly grass and covers the majority of the central portion of the property. The western most third of the property is composed of I large cedar and Douglas fir trees with light underbrush and flatter slopes ranging between 0-4%. There is an existing onsite wetland located on the western portion of the property. A wetlands report has been completed by Wetland Resources, Inc. and the delineation and associated buffer 111 are on the completed plan set. I The existing site is divided into two separate drainage basins. The majority of the site drains west to the existing wetland. However a small portion of the east side of the property drains to the existing storm drainage system located within 7th Ave. SE. The proposed development of the site will also have a split basin to maintain the onsite drainage patterns. (See the Existing Basin Map 111 located in the Section II) A Geotechnical Engineer was hired from Liu & Associates, Inc. to study subsurface conditions 111 and provide the resulting data. In their Geotechnical Report (see attached copy in the appendix) they state that there are two types of soils located on the site. The eastern portion of the site is Icomposed of Alderwood gravelly sandy loam, these soils are very dense and do not drain well. The western portion of the site is composed of Vashon Till soils that infiltrate at a long term rate I of approximately 1.0 inches/hour. (The complete Geo-tech technical Report and a map approximating the location of the separating boundary line between the soil types are included in the Appendix.) I 1 EXISTING BASIN DESCRIPTIONS Under existing conditions there are 2 drainage basins (Refer to Existing Basin Map). Basin 1 is Iadjacent to 7th Ave SE to the City of Everett drainage system. The soil is Alderwood Gravelly Sandy Loam, which is a Type C soil. This basin has a total area of 10,366 SF (0.24 acres). The I existing surface includes 4,700 SF (0.11acres) of impervious and 5,666 SF (0.13 acres) of pervious. For the purpose of calculations the existing total surface will use a Type C forest condition. I I 2 I