Bachy Soletanche offers the complete package of geotechnical solutions to design and deliver all types of in-land water and wastewater projects, including dams and reservoirs, stormwater storage facilities, wastewater treatment plants and flood alleviation schemes.

There is roughly a 1-in-4 chance over the next 30 years that large numbers of households will have their water supply cut off for an extended period because of a severe drought, which would likely cost tens of billions of pounds.

Water Sector

Climate change, aging infrastructure, a growing population and ever-increasing scrutiny from the government, regulatory bodies and the consumer, mean the industry is facing extraordinary pressure to safeguard the UK’s water and prevent the detrimental impacts of flooding, droughts and pollution.

Since the 1960s, personal water consumption in the UK has risen by approximately 60% (which equates to around 5,000 more million litres a day) and there are around 13 million more people living here.

There is roughly a 1-in-4 chance over the next 30 years that large numbers of households will have their water supply cut off for an extended period because of a severe drought, which would likely cost tens of billions of pounds. In addition to this, one in six properties in England (around 5.2 million properties) are currently at risk of flooding, with annual flood damage costs in the region of £1.1 billion across England.

This is creating an unprecedented strain on UK water supply and wastewater infrastructure, as well as an urgent need for adequate flood protection.

Bachy Soletanche provides the ground engineering expertise needed to create resilient water and wastewater infrastructure that is built with these challenges in mind. We work with our clients at early stages to develop value-engineered and future-proofed solutions that improve quality of life whilst preserving the environment and minimising risk.

We understand the importance of protecting the surrounding ecosystem and provides solutions to reduce the environmental impact of each project, be that implementing contamination management procedures or minimising disturbance to local residents. We maximise the potential of water assets so they can continue serving communities for decades to come, ensuring they are climate resilient and can accommodate our rapidly evolving world.

Our multi-disciplinary team has a comprehensive package of solutions at its disposal to suit the nuances of water infrastructure projects, including those for restricted-access sites, unpredictable strata and environmentally sensitive areas.

Some of the techniques we have applied to previous projects include grouting, sectional flight auger piling, retaining walls (secant walls and diaphragm walls), anchors and low-permeability cut-off walls such as Trenchmix. We also offer thorough ground investigation, structural monitoring and validation testing.

Case Studies

Water Aled Isaf

Aled Isaf Reservoir, Llansannan

North Wales’ Aled Isaf Reservoir was built in 1939 to regulate the flow of the adjoining River Aled. However, after 2019 geophysical surveys identified two potential leakage paths through the earth embankments at the crest of the dam. Bachy Soletanche were approached to develop a scheme to repair the paths and prevent any further damage to the dam embankments.

Environmental Solution - Lower Carno Dam Stabilisation - Slurry Cut Off Wall (4)

Lower Carno Dam Stabilisation

Built in 1911, the dam suffered with a number of leakages and complications eventually leading to the adjacent reservoir being emptied in 2005. Bachy Soletanche installed a slurry wall and comprehensive rock injection grouting to reinforce the dam in this two-phase project.

Retaining Wall Solution - Lee Tunnel - Diaphragm Wall Shaft (2)

Lee Tunnel, London

The Thames Tideway Tunnels programme is a key component of the upgrade of London’s combined sewer system. The first section to be constructed is the Lee Tunnel between the Beckton Sewage Treatment Works and the Abbey Mills Pumping Station. In the joint venture collaboration, Bachy Soletanche works included Diaphragm wall shafts, deep excavations and curtain grouting.

Retaining Wall Solution - Shieldhall Tunnel Glasgow Project - Secant and Contiguous Wall site photo (7)

Shieldhall Tunnel, Glasgow

Scotland’s largest wastewater tunnel resolves water quality and reduces flooding issues at key locations in the area served by the Shieldhall Waste Water Treatment Works. The scheme was the width of the road and therefore the sequencing and logistical planning became critical. Works included LDA piling, CFA piling, Secant retaining wall and a Contiguous retaining wall.

Foundations Solution - Restricted Access Piling - Elgin Flood Relief Scheme (1)

Elgin Flood Relief Scheme, Moray

Elgin, one of Scotland’s oldest towns, has experienced multiple flooding incidents over the last two decades. The foundation package with restricted access piling  provided support for a flood defence wall adjacent to the river. The contract was awarded based on technical excellence, programme and capabilities offered.

Foundations Solution - Cased Secant Piling CSP - Foxton Road (7)

Foxton Road, Birmingham

Piling was safely carried out very close to residential housing and the access road. Bachy Soletanche installed a 12.5 metre diameter, 14 metre deep cased secant piled (CSP) shaft and design and construct a temporary jet grout plug in the base of the shaft in Foxton Road, Birmingham. It was critical that the grout columns would overlap with no gaps left between them to ensure that the plug would be watertight.