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Water Demand Forecasting

Project future water demand year-by-year based on population growth, per capita demand, and peak factors.

Current population served by the water system.
Annual population growth rate. US avg ~0.5-1%.
%/yr
Average daily water use per person. US avg 80-100 GPCD residential.
GPCD
Ratio of max day to avg day demand. Typical: 1.5-2.5.
Planning horizon in years. Common: 5, 10, 20, 25.
years
Current treatment/supply capacity. Enter 0 to skip.
MGD

Summary

Current Avg Day Demand-MGD
End-of-Period Population-
End-of-Period Avg Demand-MGD
End-of-Period Peak Demand-MGD
Year Capacity Exceeded-
YearPopulationAvg (MGD)Peak (MGD)% Cap
Reference: AWWA M50 Water Resources Planning. Geometric growth: P(t)=P0*(1+r)^t.