https://youtu.be/AIWFR9tnVuc I've been working hard :)
Multi-Year Water Availability Analysis: Your Crystal Ball for Water Security
Finally! A rainwater harvesting simulator that shows you exactly what you need to see, using real data for your location from every day of the last 5 years.
Most calculators give you a single number based on "average rainfall" and call it done. But here's the truth: you don't live in an average year. Some years it pours. Some years bring drought. Your water system needs to handle all of them—and "average" won't tell you when you'll run dry.
That's where this changes everything.
Real Weather Data, Real Answers
This tool pulls 5 years of actual historical rainfall data for your location—not estimates, not averages, but real day-by-day rainfall from 2020-2024. Then it runs a complete simulation of your proposed system through each of those years, tracking every liter collected, every liter used, and most importantly: every day your tank runs dry.
Here's What You'll Discover:
The Big Picture
See how your system performs across multiple years. Maybe 4 out of 5 years work perfectly, but 2021 was a disaster. Now you know exactly what conditions cause problems—and how to fix them before you build.
Worst-Case Planning
The tool automatically identifies your worst-performing year and uses that for design recommendations. Why? Because if your system survives the worst year, it'll handle most years. That's conservative, reliable design.
Climate Variability Exposed
Watch rainfall swing from 1,200mm in a dry year to 1,800mm in a wet year. See how this affects your water security. Understand why "average annual rainfall" is basically useless.
When Things Go Wrong
The year-by-year performance table shows you exactly which months had water shortages, how many days you went without water, and why. This isn't abstract—it's "You'll run out of water for 8 days in February" level of specific.
Drill Down to Daily Details
Click "View Daily Details" on any month and see the full day-by-day breakdown: rainfall amounts, water collected, tank levels rising and falling, and the exact days your system failed. It's like watching your water system operate in fast-forward, letting you spot problems before spending a penny.
Interactive Year Comparison
Jump between different years with the dropdown—compare how your system handles a monsoon year versus a drought year. Watch charts and tables update instantly. See how that 30% rainfall drop in 2021 caused 3 weeks of dry taps, or how the 2023 deluge kept your tank overflowing for months.
Visual Insights That Actually Make Sense
Beautiful, intuitive charts that tell the story:
- Annual Rainfall Bars show real year-to-year variation
- Reliability Trend Line tracks your percentage of days with water across all years
- Detailed Performance Table breaks down every year with monthly rainfall, days without water, and system status
All color-coded so you instantly spot problems (red = water shortage, orange = tight but OK, green = plenty of water).
Statistical Insights That Matter
The numbers that actually help:
- "Your worst year had 15% below average rainfall"
- "Year-to-year reliability variance: ±8% (moderately variable)"
- "Perfect track record: Zero days without water across all 5 years!" (if you're lucky)
Smart Optimization Tips: We Don't Just Show Problems, We Solve Them
After revealing the weak spots, the tool gives you personalized, actionable advice:
Location-Specific Wisdom
If you're in Koh Phangan or another location with unique climate patterns, you'll get specialized guidance about dry seasons, monsoon prep, tank selection for tropical climates, and even local supplier recommendations. Generic calculators can't touch this.
Storage Strategy
"Your 2-month storage buffer is risky with a 7-month dry season. Increase to 5-6 months (32,000L) for real security during extended droughts."
Multi-Year Reliability Insights
"In 2021, your system only achieved 78% reliability and ran dry for 80 days. Consider increasing storage by 15,000L or expanding roof collection area."
Water Usage Optimization
Get specific: "Your shower usage is 65L/person/day. Low-flow showerheads and 5-minute showers could drop this to 35L/day, saving 43,800L/year!"
System Design Recommendations
Downspout sizing, gutter selection, first flush volumes, pump requirements, filter specs—all tailored to YOUR roof size and rainfall patterns.
Seasonal Strategies
Learn when to clean gutters, how to prep for monsoon season, when your tank must be 100% full, and how to manage overflow during wet months.
Maintenance Schedules
Monthly, quarterly, and annual tasks to keep your system running perfectly.
Water Treatment Advice
UV sterilization, settling chambers, filtration options—especially crucial if you're drinking this water.
The Bottom Line
This isn't just a calculator—it's a risk assessment tool, design validator, and teacher all in one. It removes the guesswork from rainwater system design by showing you exactly how your proposed setup would have performed during actual recent years.
Want to know if that 10,000L tank is big enough? Run the simulation. Wondering if you can skip the expensive second tank? Check the worst-case year. Curious whether your family's water usage is sustainable? The data doesn't lie.
In 5 minutes, you'll know more about your water system's reliability than most people learn after years of trial and error.
That's the power of real data, smart simulation, and design tools that actually give a damn about whether your system works in the real world.