Step 1: Verify RainWise rebate eligibility
- Homes in targeted combined sewer overflow (CSO) basin areas as defined by Seattle Public Utilities at https://rainwise.seattle.gov/city/seattle/overview.
Step 2: Verify at least 400 square feet of roof run-off will be captured
- This is minimum RainWise rain fall catchment area required by the Rainwise program.
- Gutters and downspouts may need to be rerouted or configured to maximize water capture – the Rainwise rebate covers this element of the installation but substantial gutter work may decrease your cost/rebate ratio.
Step 3: Verify an appropriate location for a rain garden exists on your property
- The required set-back from a house with a basement is 10’
- The required setback from a house with no basement is 5’
- Your rain garden must be 2H away from any retaining walls (i.e. rain garden must be 6’ away from a 3’ retaining wall). Additional considerations apply if your retaining wall is more than 4’ tall.
- Your rain garden must be installed with an overflow outlet to accommodate very heavy storm surges. The overflow must be adjacent to a sidewalk, driveway or street or be piped back into your functioning side sewer stand pipe.
Step 4: Measure soil drainage rate
- The drainage rate of your soil is a key factor in determining the size of your rain garden. Sandy soil drains faster, clay soil drains slower.
- This easy test requires observation of the soil drainage rate over 5-6 hours of time. This test is not necessary for cistern-only installations.
- This formneeds to be filled out by you in order to move forward with a rain garden design.
- This will be homework for youunless you want to pay us to do it for you.
Step 5: Understand rebate coverage and expense obligations
- Seattle Public Utilities pays $3.50 per square foot of roof runoff being captured by a rain garden.
- An average rebate from Seattle Public Utilities is $3000-4000, which covers 50-100% of the project costs.
- Factors impacting overall project cost include: access on your site, style, slope, topography, roof-lines, gutter work, size of garden, types of plants, etc
- You need funding available to cover the costs of the project
- You will need to have the project cost (approximately $3000-$6000) available to cover costs for our time and rain garden materials upon completion but prior to receiving the rebate.
- We require a 50% deposit and the balance upon successful completion of the final inspection with SPU.
- SPU will generally reimburse you within 30 days of receiving your rebate package
Step 6: Consultation and Design
- The first 20-30 minute site visit is complimentary to check on RainWise viability (rain garden and/or cistern) and rough specifications.
- Assuming your site is suitable for installation and you want to move forward, a detailed design is required by Seattle Public Utilities.
- Design time is $85/hr, and usually takes an additional 3-12 hours(depending on the complexity of your site), and is provided to you for:
- RainWise’s requirements, and
- Your broader landscape purposes (if you’d like a design beyond Rainwise-specifics)
- You and Contemporary Homestead will co-sign a design contract before proceeding so expectations are clear.
- We’ll take detailed roof catchment, rain garden footprint, slope, and topography measurements.
- We will also discuss your goals and objectives, plant preferences, etc
- Your completion of the comprehensive questionnaire serves as a great jumping off point for design vision and goals.
- Design time is $85/hr, and usually takes an additional 3-12 hours(depending on the complexity of your site), and is provided to you for:
- We design various styles of rain garden and try to incorporate multi-purpose plants. Plantings typically include:
- Sedges, Rushes, Sweet Grass, berries, and flowers.
- No annual veggies or root crops because of heavy metals from the roof, but berries work great (elderberry, serviceberry, huckleberry, etc.)
- Designs include a project cost estimate, plant list, and planting plan. Additional features may result in additional design time.
- Design time will include 2 hours specifically for SPU pre- and post-inspection meetings.
Step 7: Installation and Inspection
- First Seattle Public Utilities (SPU) meeting
- We meet with SPU at your house to review the design and implementation plan for your rain garden/cistern
- Installation
- We build your beautiful rain garden cisterns
- Second SPU Meeting
- Follow up meeting with SPU to review installation
- Project Invoice
- We send you the final invoice and several pieces of related documentation required by Rainwise for the rebate.
- Rebate Application
- You, the homeowner, complete a rebate application formand submit it to the city, using the instructions on the form.
- Note that SPU requires the completion of a W9 form to obtain the rebate. You will be asked to provide your social security number and your rebate will be taxed as income via SPU.
- Project funding
- We invoice you for the work performed and receive payment upon completion
- SPU sends rebate check for $3.50/ square foot of roof area redirected, generally within 30 days.
Factors in the rebate cost-benefit equation
- The cost vs rebate depends on the square footage of roof we can redirect to a cistern or rain garden (400 sf min). The more roof square footage captured, the more rebate money you will receive to apply to project costs.
- If you have the option to choose between a rain garden or a cistern, a Rain Garden gets more rebate value. When you combine a cistern and a rain garden together the larger rain garden rebate applies.
- Generally, the cistern rebate covers the installation and pays for itself. A larger cistern gets a larger rebate, but also costs more.
- Our initial planning time is spent determining logistics and scenarios so you can choose the best one. Whether you go with a rain garden, a cistern, or both, there are design + admin costs (including meeting with SPU, for example)
- For rain garden design, we typically need at least 2-3 hours to get an accurate base plan (foot print of the house and relationships of house to other features on your property), and 3-5 hours to cover the bare minimum of our design/planning/meeting/administration time. We cannot afford to give this time away.
Sound good? Then please contact us! We look forward to helping you become Rainwise!