A small pinhole in a pressurized water pipe can waste thousands of liters of water in just a few days. This pipe leak rate calculator uses Torricelli's Law to estimate the volume of water escaping through a circular hole based on the internal pressure of the plumbing system.
How the Calculation Works
The rate of flow through a leak is primarily determined by two factors: the size of the orifice (the hole) and the pressure forcing the fluid out. Higher pressure not only pushes water out faster but can also cause small leaks to expand over time.
Hole Diameter: The larger the opening, the exponentially more water is lost. A 3mm hole leaks significantly more than double what a 1.5mm hole leaks because the area increases with the square of the radius.
System Pressure: Standard residential water pressure is usually between 40 and 60 PSI. High pressure increases the velocity of the water escaping the pipe.
Coefficient of Discharge: This calculator assumes a coefficient (Cd) of 0.61, which is standard for sharp-edged orifices like a puncture in a copper or PVC pipe.
Example Leak Impact
Consider a typical scenario: A 2mm pinhole in a pipe with 50 PSI of pressure. In just 24 hours, this tiny hole can leak approximately 1,400 liters (370 gallons) of water. This is equivalent to running nearly 10 full bathtubs of water just to waste.
Why You Should Fix Leaks Immediately
Beyond the obvious increase in your utility bill, pipe leaks cause structural damage, mold growth, and can compromise the integrity of your home's foundation. Using a leak rate calculator helps homeowners and maintenance professionals quantify the severity of the issue to prioritize repairs.
function calculatePipeLeak() {
var diameter = parseFloat(document.getElementById('holeDiameter').value);
var pressurePSI = parseFloat(document.getElementById('waterPressure').value);
var hours = parseFloat(document.getElementById('timeDuration').value);
if (isNaN(diameter) || isNaN(pressurePSI) || isNaN(hours) || diameter <= 0 || pressurePSI <= 0 || hours <= 0) {
alert("Please enter valid positive numbers for all fields.");
return;
}
// 1. Convert Diameter to Meters
var radiusMeters = (diameter / 2) / 1000;
var areaM2 = Math.PI * Math.pow(radiusMeters, 2);
// 2. Convert PSI to Pascals (N/m2)
// 1 PSI = 6894.76 Pa
var pressurePa = pressurePSI * 6894.76;
// 3. Density of water (kg/m3)
var rho = 1000;
// 4. Torricelli's Law: v = sqrt(2 * P / rho)
var velocity = Math.sqrt((2 * pressurePa) / rho);
// 5. Flow Rate calculation (m3/s)
// Cd (Discharge Coefficient) approx 0.61 for sharp orifice
var flowRateM3S = 0.61 * areaM2 * velocity;
// 6. Convert Flow Rate to Liters per Hour
// 1 m3 = 1000 Liters, 1 hour = 3600 seconds
var flowRateLPH = flowRateM3S * 1000 * 3600;
// 7. Calculate Total Volume
var totalLiters = flowRateLPH * hours;
var totalGallons = totalLiters * 0.264172;
// Display results
document.getElementById('flowRateLPH').innerText = flowRateLPH.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('totalLiters').innerText = totalLiters.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('totalGallons').innerText = totalGallons.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('leakResults').style.display = 'block';
}