A sewer line is to be designed to accommodate minimum and maximum flows of 30 m³/d and 1730 m³/d, respectively, with a self-cleansing shear stress of 1 Pa. The minimum allowable sewer diameter is 200 mm, and the ASCE design aids give Manning's n values of 0.0093, 0.0107, and 0.0121 for Extra Care, Typical, and Substandard conditions, respectively; and a minimum-self-cleansing slope formula of 0.00711Q-0.5724, where Qmin is in liters per second. (a) Verify the adequacy of the minimum-self-cleansing slope formula and assess the adequacy of using the minimum allowable pipe diameter and the minimum-self-cleansing slope to meet the minimum and maximum-flow conditions. (b) What is the maximum flow that the sewer segment can safely accommodat

An existing rectangular clarifier at a drinking water treatment plant is 18 ft wide and 72 ftlong. It was originally designed for an overflow rate of 600 gpd/ft2 and it is currentlyoperating at its design capacity. Inclined-tube settling bundles are to be added and willoccupy 80 percent of the plan area, inlet flow distribution systems for the retrofitted tubebundles excludes flow through the remaining 20 percent of the surface area. Tubebundles will have a design overflow rate of 5,000 gpd/ft2. Complete an analysis todetermine the present capacity in gal/day, and the increased capacity in gal/day after thetube bundles are installed.

b.) Estimate the peak runoff flow rate observed in the combined sewer system in cfs generated only from storm water.

ENVIRONMENTAL ENGINEERING

A 16-in. sewer pipe flowing full is designed to carry a flow rate of 200 L/s (n = 0.011). Theminimum flow is 1/12 of the maximum. Find the depth and velocity at the minimum flow.