Rainwater Storage Simulator
Simulate a tank over ordered rainfall periods, showing captured water, overflow, demand coverage and backup-water needs.
- 1Enter rain and use
- 2Read the answer as you type
- 3Download or print it
Loading the worked example…
Assumptions
Results update as you type. Example figures are illustrative.
Your working data
Edit cells directly or import a CSV. Download “Input CSV” for the required column names. Up to 200 rows; scroll the table sideways for additional fields.
Detailed analysis
Exports include all results, regardless of the search filter. The HTML report includes assumptions and source data; use your browser’s Print command for PDF.
Chart shows the first 20 rows; negative values use a warm color. Click table headers to sort.
Compare up to four scenarios
Capture the current inputs, change assumptions and capture again. Scenarios are included in downloaded projects.
What this model includes
Rows are processed in their entered order. Each period’s rainfall arrives before demand; this coarse model cannot reproduce storms or daily shortages inside a period. Non-potable water budgeting only.
Import and save safely
CSV imports use your current assumptions. Project files restore assumptions, rows and saved scenarios. No automatic saving: download a project before closing this page. Imports are limited to 10 MiB and 200 rows. Calculations run in your browser; the site’s advertising and analytics follow its privacy policy.
Using Rainwater Storage Simulator
Simulate a tank over ordered rainfall periods, showing captured water, overflow, demand coverage and backup-water needs.
- Set collection area, efficiency, tank size and starting water.
- Enter rainfall and water demand for each period.
- See the tank level and short periods at the top, then download the results.
Example
The worked example includes January, February, March, April. Change the first collection area (m²) setting and compare the result with a saved baseline.
Questions & answers
What does Rainwater Storage Simulator calculate?
Simulate a tank over ordered rainfall periods, showing captured water, overflow, demand coverage and backup-water needs.
What are the important limitations?
Rows are processed in their entered order. Each period’s rainfall arrives before demand; this coarse model cannot reproduce storms or daily shortages inside a period. Non-potable water budgeting only.
Can I continue my work later?
Yes. Save a project JSON file and reopen it with Import CSV / project. It contains the working data, assumptions and up to four scenarios. Nothing is saved automatically.
What CSV columns do I need?
period, rain, demand. Download Input CSV for a compatible example. CSV imports keep your current assumptions.
Are these example figures current industry benchmarks?
No. They are illustrative values to demonstrate the model. Replace them with figures appropriate to your situation.
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