Water management in West Midlands

Clay, sandstone and old coalfields

The ground across the West Midlands changes within a few miles. Mercia Mudstone covers much of Warwickshire, Worcestershire and the east side of Birmingham, and it takes water slowly. The Triassic sandstones under parts of Birmingham, west Wolverhampton, Bromsgrove, Kidderminster and Stourbridge often drain far better. The Black Country, Cannock Chase's old coalfield and the Potteries add Coal Measures clays, made ground and old workings on top.

The region also splits between two river systems. Birmingham and the Black Country drain east through the Tame, the Rea and the Cole to the Trent. The Stour, the Avon and the Teme take the south and west to the Severn. Both have flood-prone towns downstream, so new sites are usually held to tight discharge rates whichever way they drain.

The result is that the same housing layout can need a soakaway on sandstone and a lined attenuation tank with a restricted outfall a few miles away on clay. Your engineer decides from the site investigation, and we install either.

What gets built here

A lot of the region's new building goes onto land that has been used before: foundries, works yards, canal-side wharves and former pits. On those plots the ground investigation often ends with a gas risk assessment under BS 8485, and the building needs a gas or hydrocarbon membrane as well as storage for its surface water. We install both, so one team answers for both layers.

The motorways bring the big roofs. Distribution and manufacturing sites along the M6, M42, M54 and A38 need large tanks under service yards, built to a highway loading class. Out in Warwickshire, Worcestershire and Shropshire the work is smaller and more varied: market-town housing, schools, farm reservoirs, slurry lagoons and lined basins.

Home ground from our Tamworth base

Our Tamworth base is in the middle of the patch. The M42, M6, A38 and A5 put most of the conurbation and the surrounding counties within a short drive, so a West Midlands job can often be on our programme the same week you call.

Wherever the site is, the scope stays the same. Your engineer designs and sizes the system, your groundworker digs and backfills, and we install it with welded seams, never taped, and a test weld recorded before the hole is closed.

What we've installed in the region

Recent West Midlands work covers most of what we do:

• A 115m³ attenuation tank at Swanhurst School in Birmingham.
• A 500m³ attenuation tank in welded HDPE on a residential development in Bournville.
• A 3,500m² lined attenuation basin in 1mm HDPE for new homes in Worcester.
• A pond on the HS2 route near Coventry, lined in 1mm HDPE and tested seam by seam.
• A 2,000m² slurry lagoon at Bodymoor Heath, lined in welded LLDPE between two layers of fleece.