Free Rainwater Assessment
See how supply and demand compare annually and through the year, and identify practical next steps.
Potential inflow / year51,206 gal
Selected demand / year20,413 gal
Example results · Your project will differ
Design Smarter Rainwater Systems.
See what your roof can collect, how it compares with the water you use, and what a practical rainwater system could do for your property.
Choose the Level of Planning You Need.
Start with a free rainwater assessment. When you are ready to explore tank size and daily performance, continue to Rainwater Tank Sizing.
Next level
Rainwater Tank Sizing
Go beyond annual potential and compare practical tank sizes using historical daily weather and the timing of project water uses.
Usable storage22,000 gal
Modeled demand served90%
Example results · Your project will differ
Compare the Planning Tools
Free Rainwater Assessment
- Use location-based historical rainfall and climate data
- Trace or enter rainwater collection areas
- Add seepage, condensate, and other supported sources
- Trace landscape zones and water features on the map to automatically estimate water demand
- Use irrigation schedules, water bills, meter readings, or known amounts
- Estimate toilet flushing and laundry demand based on fixtures and use
- Add additional water uses as needed
- Compare rainwater supply with selected water uses
- See seasonal supply-and-demand patterns
- Identify practical next steps
Rainwater Tank Sizing
Everything in the Free Rainwater Assessment, plus:
- Choose a planning goal to model tank performance
- Keep the tank smaller
- Balance size and savings
- Increase water savings efficiently
- Maximize water savings
- Avoid backup water
- Reduce runoff
- Include protected fire-reserve storage when needed
- Receive a recommended storage capacity based on your goal and decades of local daily weather data
- Understand why the recommendation was selected for your chosen goal
- Compare practical tank sizes by demand served, backup water, overflow, and year-to-year performance
- Explore tank configurations that meet the recommended storage capacity
Built for real site-water planning
Site-specific geometry
Trace roofs, landscape zones, and water features directly on the map so their actual areas feed the analysis.
Flexible ways to estimate water use
Estimate demand from landscape conditions, irrigation schedules, water bills, meter readings, known amounts, and fixture-based use.
Daily historical modeling
Model supply and demand using decades of local daily rainfall and evapotranspiration—not just annual averages.
Choose a water-storage goal
Model storage around priorities such as keeping the tank smaller, balancing size and savings, maximizing water savings, reducing backup water, or capturing more runoff.
Storage performance and tank sizing
Simulate the tank day by day to see when it fills, overflows, runs short, or carries water through dry periods—and compare storage sizes for different project goals.
The whole site-water balance
Bring rainwater, seepage, condensate, indoor uses, irrigation, and water-feature demand together to understand how multiple supplies and demands interact through time.
How It Works
Define Water Sources
- Trace or enter rainwater collection areas
- Add seepage, condensate, and other supported sources
- Load historical rainfall and climate data based on project location
- Upload custom weather data when needed
Estimate Water Uses
- Trace landscape zones to estimate irrigation demand
- Trace pools, ponds, and fountains to estimate water-feature refill
- Use irrigation schedules, water bills, meter readings, or known amounts
- Estimate toilet flushing and laundry demand based on fixtures and use
- Add additional water uses as needed
Review the Rainwater Opportunity
- Compare annual rainwater supply with selected water uses
- See seasonal differences in supply and demand
- Identify practical ways to improve the opportunity
Explore the Next Level of Storage Planning
- Choose a planning goal to model tank performance
- Include protected fire-reserve storage when needed
- Receive a recommended storage capacity based on your goal and decades of local daily weather data
- Understand why the recommendation was selected for your chosen goal
- Compare practical tank sizes by demand served, backup water, overflow, and year-to-year performance
- Explore tank configurations that meet the recommended storage capacity