Richard Allitt Associates continues to support Severn Trent Water with wastewater resilience

Severn Trent Water’s catchment planning and commitment to managing the resilience of its wastewater network and reduction of flooding and pollution will be underpinned by project work from two RSK Group companies, Richard Allitt Associates (RAA) supported by Binnies UK.

Severn Trent will invest in the framework over the next four years to model a variety of scenarios that will inform the design of future investment to improve the wastewater network and assets around the region.

The Water and Wastewater Modelling Framework will look at high-level and long-term plans across the Severn Trent and Hafren Dyfrdwy regions, covered by 14 strategic planning areas based on river basin management districts.

These are further broken down into more than 1,000 ‘tactical planning units’ based on wastewater treatment works catchments.

RAA was successful in both the regional and water industry national environment programme (WINEP) parts of Lot 2 – wastewater hydraulic modelling and catchment planning.

Work will include model maintenance and enhancements, long-term catchment planning, supporting the development of the drainage and wastewater management plan’s (DWMP) requirements, DWMP delivery and developing catchment strategies and modelling (maintenance, enhancement and upgrade of the existing modelling stock).

AMP7 Water Framework Directive investigations and storm overflow assessment framework investigations will also be carried out.

Martin Allitt, RAA managing director, said the firm has worked with Severn Trent Water on wastewater modelling since 2001 and described the ongoing work as "a great testament to the relationship we have developed over that time and our understanding of its priorities and commitments".

“Understanding the hydraulic, operational, structural and environmental needs of our wastewater catchments is crucial for Severn Trent’s long-term strategies for wastewater collection and treatment and sustainability," he said.

"The company has an ongoing ambition to ensure investment decisions are based on accurate and current information about sewerage and pluvial and fluvial drainage (rainwater and flood water).

"The DWMPs are a key part of this, and meeting the future needs of customers will require root cause analysis investigations at a local level.”

Martin said the project enabled RAA to continue to support Severn Trent Water in all aspects of wastewater management.

During the initial three years of the framework, the emphasis will be on planning and modelling activities to help the company meet its obligations with regard to combined sewer overflows (CSO) and reduce its impact on the environment.

“We will also be involved in planning activities as part of cycle two of the DWMPs, building on work we undertook during cycle one,"  Our work will be focused across the Severn Trent Water operational region covering Gloucestershire and Worcestershire – 329,300 hectares (3293 km²). Within this area, there are 27 sewerage management plan areas covering 121 wastewater treatment catchments. These catchments serve a population of approximately 1.2 million customers (12% of all Severn Trent wastewater customers). In addition to this work, this framework allows us to continue to support Severn Trent Water by investigating and developing solutions to mitigate 50 of the most problematic CSOs across its region.”

Rob Murrell, Asset Management Modelling Team Lead, said: “Part of our environmental commitments are that Severn Trent operations will cause no harm to any stretch of water in our region by 2030. While this is an ambitious target, it is one that we are absolutely committed to achieve and the services supplied through this framework will play a key role in helping us to get there.

Binnies Director of Water Utilities Rachel Pether said: “Understanding the capacity of existing networks and supporting our clients to provide solutions to problems such as CSO activation has always been important to us.

“Supporting RAA in this exciting new framework with Severn Trent Water enables us to collectively build on the great work already undertaken in our tried and proven delivery to enhance the service levels to Severn Trent’s customers and the environment. We are particularly pleased to be extending our demonstrable capability in supporting the important WINEP programme.

“Our wide experience through the full life cycle of projects from feasibility to construction and asset management enables us to bring unique perspectives at the planning stages, which will be a key part of this framework. This strategically important win aligns with Binnies’ sense of purpose of enhancing lives and the community. We look forward to working together in the years ahead.”