Storm overflows: automating the audit

Storm overflows occur when the sewerage network is at risk of being overwhelmed, such as during heavy rainfall when a lot of water drains into the system in a short space of time. Southern Water, like other water companies, must assess the impact of these overflows. We’ve developed an audit tool to automate the verification of the hydraulic models that underpin this process.

To evaluate the impact of a storm overflow, Southern Water follows the process defined by the Storm Overflow Assessment Framework (SOAF). This involves building a hydraulic model of the process which is verified using flow survey data.

Appling technology to hydraulic model reviews

As independent experts, we provide Southern Water with critical audits of their updated hydraulic models. To streamline model development and verification we have developed an innovative tool to deliver these audits more efficiently, providing automation, clarity and collaboration throughout the process.

Our tool allows for the hydraulic models in the current phase of 25 SOAF investigations to be consistently reviewed to ensure that they are fit for purpose and accurately represent the impacts of the overflows.

The impact of our audit tool has been far reaching. In addition to underpinning the SOAF process, it’s use has been expanded to inform Southern Water’s strategic growth studies, demonstrating the value it adds to their operations in the long term.