GPM to MGD Converter
Convert US gallons per minute (GPM) to million gallons per day (MGD). Divide by 694.444, or multiply by 0.00144. MGD is the standard capacity unit for municipal water and wastewater treatment plants in the United States.
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GPM to MGD conversion resultFree download
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How It Works
Pumps and process lines are rated in GPM, but plant capacity, permit limits and regulatory reporting are expressed in MGD. Converting between them is routine in water and wastewater engineering. Because MGD is a daily figure and GPM is per minute, the factor carries the 1440 minutes in a day as well as the million-gallon scaling.
GPM to MGD Formula
MGD = GPM × 0.00144
One US gallons per minute equals 0.00144 million gallons per day. Going the other way, one million gallons per day equals 694.444 US gallons per minute.
Worked Example
Converting 100 GPM:
100 × 0.00144 = 0.144 MGD
GPM to MGD Conversion Table
| GPM | MGD |
|---|---|
| 1 GPM | 0.00144 MGD |
| 5 GPM | 0.0072 MGD |
| 10 GPM | 0.0144 MGD |
| 25 GPM | 0.036 MGD |
| 50 GPM | 0.072 MGD |
| 100 GPM | 0.144 MGD |
| 250 GPM | 0.36 MGD |
| 500 GPM | 0.72 MGD |
| 1000 GPM | 1.44 MGD |
Going the other way? Use the MGD to GPM converter. For any other unit pair, the full flow rate converter handles all ten supported units.
FAQ
Common questions about converting US gallons per minute to million gallons per day.
Frequently Asked Questions
How do I convert GPM to MGD?
Divide the GPM value by 694.444, or multiply by 0.00144. For example, 1000 GPM / 694.444 = 1.44 MGD.
How many GPM is 1 MGD?
One million gallons per day equals 694.444 US gallons per minute. This is 1,000,000 gallons divided by the 1440 minutes in a day.
Why do treatment plants use MGD?
MGD matches the scale at which plants are designed and permitted. A plant rated at 10 MGD would be 6944 GPM, and daily figures align naturally with discharge permits, flow reporting and demand projections, which are all tracked per day.
What is 500 GPM in MGD?
500 GPM equals 0.72 MGD. A quick check is that 700 GPM is very close to 1 MGD.
Is MGD based on US or Imperial gallons?
MGD as used in US water and wastewater practice means million US gallons per day. One US gallon is 3.78541 litres, so 1 MGD equals about 3785 cubic metres per day.
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