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Watched informational video on rebate program and process. A site assessment of my property was completed by city staff. Soil infiltration test certification was completed, turned in and signed off on. Read and understood the 10‐year rain garden maintenance agreement. Completed a rain garden layout and planting plan that includes: placement of garden in relationship to yard ponding depth and size of garden clear delineation of inflow and overflow full planting plan, distinguishable by planting zones Name: Site Address: Phone: Zip Code: Email: Turn this checklist in with a signed copy of your soil infiltration results and your rain garden design and planting plan. Application Checklist Let it Rain program rain garden rebate ---PAGE BREAK--- You MUST perform this test before considering a rain garden. Dial 811 before you dig! Perform this test after your site has been assessed by the city. Results should be emailed to the city. [EMAIL REDACTED] or [EMAIL REDACTED] How water flows through soil plays a significant role in the decision to build and size a rain garden. The characteristics of subsoil (the layer under topsoil) play a role in water movement. Subsoil that is made up of glacial till or clay prevents infiltration. If there is enough rain with this type of subsoil, the topsoil becomes saturated, leaving no place for the water to go regardless of the characteristics of the topsoil. To properly size your rain garden perform the following infiltration test: 1. Dig a hole that is 24 inches deep and at least 6 inches across. 2. Add a wooden stake to the bottom of a yardstick. Duct tape works to attach the stake. Place the yard stick in the hole with end of yard stick flush with the bottom of the hole. 3. Fill the hole with water to a minimum depth of 12 inches and let the water drain completely. 4. SKIP THIS STEP if doing test during the wet season (December through April). Repeat filling hole with water to 12‐inch depth and drain a second time. ONLY do second filling with water if test is done in summer. 5. Start in the morning for the next fill, making sure it is within 24 hours of the initial fill of water. Fill the hole with water to a minimum 12‐inch depth and a. Measure the water height every hour. Note your results in the table included with this form or create your own logbook. b. Continue to note your results until the rate of infiltration stabilizes (the water is no longer draining and the water depth has stayed steady for 2‐3 hours). c. Use results to calculate the infiltration or drainage rate (inches/hour) of the soil. 6. Multiple test holes are recommended especially if the first test hole fails (i.e. does not drain). It is best to dig test holes at least 3‐5 feet apart and be sure to follow Steps 1‐ 5 for each test hole. During the site assessment, city staff will identify the best locations for soil test holes. Soil infiltration test certification WARNING: If you find any of the following conditions during your test You hit hard pan (dense clay) Your test hole does not drain at least ¼ inch per hour Your test hole fills with water after or during your digging attempt your site may not be suitable for a rain garden or other stormwater infiltration. ! ---PAGE BREAK--- Results table (example) Date of test Hole # (multiple holes recommended) Water fill # Elapsed time Water depth Infiltration rate Notes 1/24 #1 1st fill n/a 12” Initial fill, no data 1/25 #1 2nd fill 12 hrs. 12” 1” per hr. Will test 2 more holes Your results – You can use a separate piece of paper to keep results. This is just a guide. You must sign below and return this document with your application to be eligible for the City of Everett rain garden rebate. I certify that I followed the procedures outlined in this document to determine my rain garden sizing. I have chosen to size my rain garden in accordance with these results. I understand that rain gardens are sized for moderate rain events and that regardless of the infiltration ability of my soil that my rain garden must have a clear and safe overflow path according to Let it Rain program details. Test performed by: Homeowner Other Print Name Signature Date Date of test Hole # Water fill # Elapsed time Water depth Infiltration rate Notes Soil infiltration rate calculation Soil infiltration rate is calculated by dividing inches of water infiltrated by hours you observed. For the example above, the infiltration or drainage rate is: 12 inches divided by 12 hrs. =1 inch per hour. Therefore, the example drainage or infiltration rate is: 1 inch/hour