2021 LEXINGTON AVE 2018-03-07 - Laserfiche WebLink

, 2. EXISTING CONDITIONS SUMMARY The site covers approximately 0.22 acres. As previously mentioned the site is developed and contains an existing SFR (to be replaced with the new duplex), driveway (to be removed) and a couple sheds. Oaks Ave right-of-way runs along the east side of the property and Lexington Ave right-of-way runs along the south side of the property. Since the existing site contains an SFR and driveway, which will be replaced by a new duplex and driveways, the net new impervious after final construction of the project totals less than 2,000 sf. The site previously contained approximately 2,084 sf and the site after final construction will contain approximately 3,917 sf. Access to the site will be from the alley to the west which takes access from Lexington Ave to the south. Approximately 3,917 sf (0.09 acres) of the site will be impacted by new plus replaced impervious surfaces with the entire site, approximately 9,576 sf (0.22 acres) being disturbed as needed for the clearing/grubbing and restoration of the existing site. The proposed area of disturbance drains to the east. This project will not affect any off- site flows from passing through the site as in the existing condition. All of the proposed impervious surfaces for this project will be dispersed on-site over existing lawn or amended soils. By not grading or compacting the majority of the pervious surfaces to remain after construction in the area of disturbance a maximWm amount of site runoff from the developed project will be absorbed into the existing on-site soils. The USDA Web-Soil Survey was used to determine the existing soil conditions for the parcel. Refer to Figure 4. The soils are mapped as Alderwood-urban land complex. The general site slopes, in the area of disturbance, are flat to moderate and average approximately 7 percent down to the east. Based on the existing soil information and the setbacks of the proposed improvements from any of the property lines or critical areas there is little potential for erosion or sedimentation during construction, assuming the basic BMPs included in the SWPPP are installed and maintained properly. Refer to Figure 2 for an existing basin map. Haack—Lexington Duplex 16-1112 January 2017 Page 4