Sustainability

Protecting the natural environment

Working for Anglian Water in the @one Alliance, we’re building storm water capacity helping to manage climate related challenges.

Protecting the natural environment

Anglian Water is investing £47m over the coming year to build 35 new storm tanks in the East of England region, which is known for its flat terrain and susceptibility to climate-related challenges such as flooding and heavy rainfall.

The tanks will significantly increase stormwater storage capacity, meaning sites can store excess flows during heavy rainfall for treatment later on. The new tanks will prevent untreated water from entering rivers and coastal areas, protecting the East of England’s natural environment.

The programme builds on the success of similar work during the AMP7 (Asset Management Programme) period when, over the course of five years, 112 storm water tanks were constructed.

The Storm Tank Programme was split into a series of individual projects, each designed to meet the unique demands of its location while adhering to a consistent programme approach to maximise efficiency and resource management. We led on the design, development and construction of many of these schemes as Principal Contractor.

Across the programme, works covered the following improvements.

Storm tank construction and upgrades: construction of new storm tanks and the enhancement of existing ones. The majority of the new tanks were above ground glass coated steel tanks, designed to provide additional storage capacity during peak flows, preventing untreated water from entering natural watercourses. Hydraulic profiles and modelling were used to determine optimal tank sizes and configurations for each site. Above-ground tanks were all constructed from ground level upwards to avoid the teams working at height.

New infrastructure features: each site required varying enhancements to the current infrastructure. These included new side weir storm overflows, installed from the feed channel upstream of the existing flow-to-full treatment flow meters, to help manage the incoming flow into some of the storm tanks. New storm pumps, storm return pumps and return pipework was also installed.

Upgraded infrastructure: many of the projects required critical installations, including transformers, motor control centres (MCCs) and advanced pumping stations. These ensure effective stormwater transfer and flow management during peak conditions while minimising the environmental impact.

Cleaning & maintenance systems: as part of the commitment to Anglian Water’s operational teams, many cleaning and maintenance systems were provided. These included new manual washing systems, wash-water feed pumps, new tank cleaning system with externally mounted nozzle rings, as well as modifications to the existing tanks for cleaning.

Benefits
The storm tank solution is providing much greater resilience to the risks of flooding, with stormwater storage capacity significantly increased. This reduces the risk of sewer overflows, helping to protect local communities, ecosystems and infrastructure from the damaging effects of stormwater.

It’s also improving compliance with rigorous environmental regulations and adherence to strict discharge standards. This not only protects ecosystems but also contributes to cleaner waterways, benefiting wildlife and communities alike.

Learning from the AMP7 programme is now being carried forward into AMP8 and the next phase of work. The programme’s success underlines the importance of collaboration, innovation and a long-term vision in overcoming complex challenges.