WebSep 2, 2024 · Project sites that must also meet Minimum Requirement #7 must match flow durations between 8% of the 2‑year flow through the full 50‑year flow. Designers selecting this option cannot use Rain Gardens to achieve the LID Performance Standard. They may choose to use Bioretention to achieve the LID Performance Standard. 4.2.5.3 The List … WebMar 27, 2024 · T5.10A Downspout Full Infiltration Systems 5 5 0 yes no no 0.40 T5.10A Downspout Full Infiltration Systems 4 4 0 no no yes 0.09 T5.10B Downspout Dispersion Systems 9 9 0 yes no no 0.46 T5.12 Sheet Flow Dispersion 9 9 0 yes no no 0.40 T5.13 Post-construction Soil Quality and Depth 13 13 0 yes no no 2.91 T5.14A Rain Gardens 2 …
Stormwater Clark County
Web1. Full dispersion or downspout full infiltration 2. Rain garden or bioretention 3. Downspout dispersion system 4. Perforated stub-out connections 5. On-site detention system or fee-in-lieu of on-site detention authorized by the City Engineer (applicable if options #1-4 are infeasible and drainage from the site will be discharged to a storm WebInfeasible 26 Field testing indicates soils have a measured underlying soil infiltration rate less than 0.3 inches per hour (Note: field infiltration tests are not required for permeable pavement surfaces, but must be used to demonstrate infeasibility). Infeasible Design soil infiltration rate less than 0.15 inch per hour incorporateweb uk
Low Impact Development System Worksheet - Snohomish …
WebWhere pavement is proposed, it must be permeable to the extent feasible unless full dispersion is employed. Roofs: 1. Full Dispersion in accordance with BMP T5.30: Full Dispersion , or Downspout Full Infiltration Systems in accordance with BMP T5.10A: Downspout Full Infiltration . 2. WebWhen the water reaches the base of the downspout it can be directed into an infiltration system. If roof runoff is infiltrated according to the requirements of BMP T5.10A: … Webdry well por BMP L602 — Downspout Infi tration. Downspout full infiltration facilities shall be designed per Vo umc 3, Section 2.3_3_ A soils report per Section I is required to comp eta the determination of infeasibi ity orto design the system if tho minimum infiltration trench length or a m nimum drywell size will fit on the project site. incorporatewear log in