Feasibility Study of laying Trunk & Gravity main, design and costing

Wessex Water is to supply the new development of 2000 houses in Poundbury with drinking water. It has been determined that a pumping station (PS) at Burton will supply water from the regional main to a service reservoir (SR) at Lambert’s Hill, which in turn will allow water to flow by gravity to the urban development. There are therefore two pipes that need to be designed, the pumped trunk main from Burton PS to Lambert’s Hill SR, and the gravity distribution main from Lambert’s Hill SR to Poundbury. You are tasked with examining the alternatives and proposing the most cost effective solutions; your designs will encompass the route, pipe material, pipe diameter and, for the trunk main, the outline pump arrangement. You will also advise on the need for pressure surge protection.

The pipeline’s route will be governed by a number of factors, amongst them system hydraulics (ground elevation and slope), land use (landowners, road / rail and river crossings), sensitive areas (AONB, CWS, SSSI, SAM) and access (construction and maintenance). The pipeline’s diameter will be governed by system hydraulics (pressure, flow, friction, length) and the material will be governed by ground conditions and costs. The pertinent requirements from the Wessex Water Design Standards are given below (for more information please refer to the full document on the module website):