A township of 25,000 inhabitants is to discharge treated domestic sewage to the neighboring stream which has a least flow of 0.25 m3/s and a 5-day BOD of 3 mg/L. Water consumption in the town is 175 L/capita.day, and the BOD contribution is 0.06 kg/person.day. If the BOD in the stream below the sewage outfall is not to exceed 4 mg/L, verify the maximum effluent BOD permissible