Design Flow from Population (Average, Peak, Minimum)

Average, peak, and minimum design flow from a service population - the flow the rest of the water and wastewater bench takes as an input. Average daily flow = population x per-capita flow (gpcd); peak = average x the Harmon factor PF = 1 + 14/(4 + sqrt(P)); minimum = average x the Gifft ratio 0.2 x P^(1/6), P in thousands. 50,000 people at 100 gpcd -> 5.0 MGD average, 11.3 MGD peak (PF 2.26), 1.9 MGD minimum. The peak factor falls as the system grows (1.39 at 1,000,000). Domestic sanitary flow only; add infiltration/inflow and industrial load separately. Ten States Standards and the state design criteria govern.

avg_gpd = population x gpcd; avg_mgd = avg_gpd/1e6; PF = 1 + 14/(4 + sqrt(P)); peak = avg x PF; min = avg x 0.2 x P^(1/6) (P = population/1000).

Sanitary design flow from population with the Harmon peaking factor and the Gifft minimum-flow ratio, standard sanitary-engineering practice (Metcalf & Eddy, Wastewater Engineering; Ten States Standards), by name.

The Harmon and Gifft empirical factors and the average-flow-from-population relation are standard published sanitary-engineering results; the per-capita flow is the user's own design basis.

Estimate. Operator of record and primacy agency govern.

Field names used by the API: population, per_capita_gpcd, avg_flow_mgd, harmon_pf, peak_flow_mgd, min_flow_mgd

• Average daily flow population x per-capita flow (gpcd)sanitary engineering
• Harmon peaking factor PF = 1 + 14/(4 + sqrt(P)), P in thousands (peak = avg x PF)Harmon / Metcalf & Eddy
• Gifft minimum ratio min/avg = 0.2 x P^(1/6), P in thousandsGifft (1945)
• Scope domestic sanitary flow only; I&I and industrial load added separatelyscope of this tile