External Water and Sewer Networks

The external network is buried, so nobody looks at it and nobody complains about it until it fails. And then the repair is an excavation in a paved street under an occupied building, at several times what it cost to build. This guide gathers its calculations in one place: the demand, the diameter, the gradient, the depth, the station and the test. The system boundary and the four networks, estimating water demand and storage, water main diameter by Hazen-Williams and the residual pressure, sewer flow and its design by Manning at partial flow with the self-cleansing velocity, manholes and their depths, storm drainage by the rational method, lift stations and rising mains, materials and testing, then crossings and handover. 10 fully worked examples, every number checked. To BS EN 805 · AWWA M31 · M32, BS EN 752 · BS EN 1671 · Sewers for Adoption, Manning · Harmon · Hazen-Williams. 31 pages · Level EL 200 · Revision A. Whoever owns revision A receives every later revision free.