Hey Everyone! Long Time :)

I'm sharing this free tool — something that I made — that helps you simulate and understand Rainwater Harvesting in your location and climate.

This is no ordinary calculator...

SO... IF you happen to be looking to set up a rainwater harvesting system, this is well worth a look!
Might save you a lot of problems down the line!

Most rainwater calculators give you a single number based on average rainfall and call it a day.

But here's the problem:

You don't live in an "average" year.

Some years it pours. Some years there's drought.
Your water system needs to handle all of them.

That's where this simulator comes in.

🌧️ Real Weather Data, Real Answers

This tool pulls 5 years of actual historical rainfall data for your location — not estimates, not averages, but the real day-by-day rainfall from 2020–2024 (or your location’s available data).

Then it runs a complete simulation of your proposed system through each of those years, tracking:

• Every liter collected
• Every liter used
• 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 year 3 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 works in the worst year, it'll work in 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" doesn't tell the whole story.

⚠️ When Things Go Wrong

The year-by-year performance table shows you:

• Which months had water shortages
• How many days you went without water
• Why (low rainfall? tank too small? both?)

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:

• Full day-by-day breakdown
• Rainfall amounts
• Water collected
• Tank levels rising and falling
• Exact days your system failed

It's like watching your water system operate in fast-forward — spot problems before spending a penny.

⚡ Interactive Year Comparison

Use the year selector dropdown to jump between years:

• Compare monsoon year vs. drought year
• Watch charts and tables update instantly
• See how 30% less rain in 2021 = 3 weeks without water
• Or how 2023’s deluge kept your tank overflowing for months

📈 Visual Insights That Make Sense

Beautiful, intuitive charts:

Chart	What It Shows
Annual Rainfall Bars	Year-to-year variation
Reliability Trend Line	% of days with water across all years
Detailed Performance Table	Monthly rainfall, days dry, system status

Color-coded:

• 🟢 Green = Plenty of water
• 🟠 Orange = Tight but OK
• 🔴 Red = Water shortage

---

🧮 Statistical Insights That Matter

The tool crunches the numbers:

• "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!)

🛠️ But Wait, There's More: Optimization Tips

After showing you the problems, the tool doesn't leave you hanging.

Scroll down to Smart Optimization Tips — personalized advice based on your situation:

Tip Type	Example
Location-Specific Wisdom	Koh Phangan’s 7–8 month dry season, monsoon prep, tropical tank selection, local suppliers
Storage Strategy	"Your 2-month buffer is risky. Increase to 5–6 months (32,000L) for drought security."
Multi-Year Reliability	"In 2021, only 78% reliability — ran dry for 80 days. Add 15,000L or expand roof area."
Water Usage Optimization	"Shower: 65L → 35L/day with low-flow heads = 43,800L saved/year!"
System Design	Downspouts, gutters, first flush, pumps, filters — tailored to your roof & rainfall
Seasonal Strategies	When to clean gutters, fill tank 100%, manage overflow
Maintenance Schedules	Monthly, quarterly, annual tasks
Water Treatment	UV, settling chambers, filtration — especially for drinking

---

The Bottom Line

This isn't just a calculator — it's a:

• Risk assessment tool
• Design validator
• Teacher

It takes the guesswork out of rainwater system design by showing you exactly how your setup would have performed during recent years.

Want to know if that 10,000L tank is big enough?
→ Run the simulation.

Wondering if you can skip the second tank?
→ Check the worst-case year.

Curious if your family’s 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 care about whether your system works in the real world.

Ready to see how your system really performs?

Check it out here

https://watersecurity.netlify.app/