Thames Water has appointed Barhale to deliver three sewer and drainage schemes intended to support housing growth and wider development in Brent Cross (London), Benson (Oxfordshire) and South Basingstoke (Hampshire).

The contracts were awarded under Thames Water’s AMP8 Major Projects framework for Developer Services and Infrastructure Programmes, a multi‑hundred‑million pound programme aimed at providing infrastructure to meet developer needs. The framework covers larger and more complex works such as diversions, requisitions and lateral drains.

In north London, adjacent to the Peel Centre at Rushgrove Park in the London Borough of Barnet, Barhale will design and build an offline foul storage attenuation system. The work includes a diversion from an existing foul sewer, construction of a 560m3 shaft tank to provide additional storage and to intercept flows from a combined sewer overflow (CSO) discharging to a watercourse and a pumped return to an existing manhole.

The scheme is linked to Barnet council’s proposed upgrades to Rushgrove Park, which also include improvements to the park’s tennis courts. Thames Water says the storage and interception measures are intended to reduce spills to the local watercourse and increase network resilience as nearby development proceeds.

In Benson, Oxfordshire, Barhale will build and commission a new 500m foul gravity sewer and 15 new manholes to serve planned housing and to increase capacity for current residents. The new route will shorten parts of the existing network and is intended to improve resilience and reduce future risk of sewer issues as the area grows.

Works in South Basingstoke cover two locations. On Winchester Road Barhale will construct a new 590m sewer and associated manholes. At Kempshott Lane the contractor will increase capacity on an existing 484m sewer and upgrade the existing manholes. These interventions are designed to accommodate connections from forthcoming housing developments.

Design work for the schemes will be carried out by Barhale’s specialist design unit, ESL.

Thames Water’s AMP8 business plan – the current five‑year investment period set by the industry regulator Ofwat – places greater emphasis on delivering capacity and resilience for new developments while reducing environmental impacts. Local sewer upgrades and offline storage tanks are among the typical measures water companies use to manage increasing demand from housing and to limit discharges from combined sewer overflows, which have attracted regulatory and public scrutiny in recent years.

Barhale contract manager Florin Edu said: “These are important schemes which are either meeting or anticipating growth at each location.

“They are also providing a substantial benefit to existing residents and businesses by increasing network resilience and increasing the network’s ability to cope with increasingly extreme weather conditions.”

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