Understanding and addressing reservoir safety and leakage risks

Overview

These presentations highlight key projects addressing reservoir safety risks, regulatory changes, and leakage remediation. They explore the assessment of non-statutory reservoirs, emergency responses at a historic site, and engineering solutions for embankment stability. Together, they provide valuable insights into proactive risk management and effective remediation strategies.

Understanding the Reservoir Safety Risks of Non-Statutory Reservoirs

In 2022, Severn Trent Water (STW) engaged Arup to assess reservoir safety risks for 71 sites with capacities between 10,000 and 25,000m³.

Due to amendments in the Reservoirs Act, these reservoirs may soon be regulated, increasing STW’s statutory responsibilities.

The project evaluated financial risks associated with regulatory changes by analyzing each reservoir’s safety. Both operational and capital requirements were considered to manage risks proactively.

This presentation covers the assessment methodology, key findings on safety risks, mitigation measures, and insights into the challenges and opportunities encountered.

Leakage Remediation at a Small Heritage Reservoir

Abbeydale Industrial Hamlet in Sheffield is a historic steelworking site with a reservoir that powered machinery. The site, including the reservoir, is a Scheduled Monument with multiple listed structures, dating back to the 17th and 18th centuries.

Despite its small capacity, the reservoir has a history of leakage. A 2022 investigation aimed to identify suitable repairs.

In May 2023, severe leakage into a Listed building prompted emergency action.

This presentation discusses past issues, previous and recent investigations, and the development of long-term remedial measures.

Leakage Remediation at the Hampton Distributing Reservoir

Built in the 1900s, Hampton Distributing Reservoir in southwest London has a clay core embankment, an 800m perimeter, and a 32,000m³ capacity.

Since 2011, crest leveling surveys detected settlement, later confirmed by a 2020 geophysical survey, revealing a leakage path at the foundation level.

To mitigate instability risks, remedial measures, including permeation grouting using Tube-a-Manchette (TaM), were proposed to reduce seepage.

Challenges included restricted working space and access. The project involved investigative works, feasibility studies, and the design and execution of grouting.

This presentation outlines the project’s key aspects, challenges, and lessons learned.