6708 CADY RD 2025-03-31 - Laserfiche WebLink

INTRODUCTION Inspection and maintenance requirements may change in the future, and this manual does not exempt this facility from any future changes in inspection and maintenance requirements. The project includes 8 livable Pallet Shelters along with bathroom and laundry facilities, in the rear of a lot occupied by the existing Faith Lutheran Church. The project will also include gravel surfacing around the Pallet Shelters, and a small area of asphalt for ADA-compliant grade transitioning. No vehicular travel is expected across these new impervious surfaces. Drainage design requirements were made in accordance with 2019 DOE Stormwater Management Manual for Western Washington. Stormwater runoff from the gravel, roof and asphalt impervious surfaces will drain off the gravel pad area and is intended to disperse into the surrounding native vegetation per BMP T5.12 Sheet Flow Dispersion of the DOE Manual. No actual facilities are constructed for this BMP, rather the grading of the impervious surface on the site is intended to allow stormwater to exit the site and disperse into the native vegetation surrounding the facility. Facility maintenance and inspection should occur on a yearly and as-necessary basis to maintain gravel pathway areas such that stormwater can freely flow to the edges of the gravel area and disperse without impediment. This may include, but not be limited to the adjustment of surface grades back to design intent to encourage designed stormwater flow routes, filling in of"potholes"or low spots that might develop as the result of use, and/or the removal or relocation of features that may impede stormwater flow as per design. Additionally, 10 feet of native vegetation beyond the edge of the gravel area will be utilized for dispersion of stormwater runoff from the onsite improvements. This 10 feet will remain in a vegetated state similar to the surrounding grassed area. This grassed area maintained in a manner and scheduling in keeping with the desired maintenance habits of the existing facility. No items other than grass or native plantings shall be located within the 10 foot area in order to facility proper dispersion of stormwater. An example maintenance log is included on page 2. BMP T5.13 Post Construction Soil Quality and Depth is also utilized for disturbed project areas that are not covered with impervious surfaces. The amended soil areas should be planted with appropriate groundcover to match the surrounding vegetation and maintained in a manner and scheduling in keeping with the desired maintenance habits of the existing facility. Inspections to confirm functionality can be performed as necessary, but no schedule is required due to the nature of the BMP as it will exist in the developed state of the project. 1