Free Web Tool · DENR / NEDA

WWTP Per-Capita Sizing

Quick wastewater treatment plant sizing from population equivalent — design flow, peak factor, BOD/SS loadings, and a rough activated-sludge tank volume.

Input

0.2-0.4 conventional AS
1.0 = nominal

Results

Avg flow Q_avg (m³/day)
Peak design flow Q_max
BOD load (kg/day)
TSS load (kg/day)
Inlet BOD concentration
Aeration tank volume V
Hydraulic retention HRT (hr)
Method

Q_avg = pop·wwPC. Peak Q = Q_avg · PF (rule of thumb: PF = 4 / pop^0.18 capped). BOD load = pop·BOD_pc. V = (BOD_load · 1000) / (F/M · X) [g·d /(g/g/d ·g/m³) = m³]. HRT = V·24/Q_avg.