Proceedings

Ampleforth Village STW: AMP 7 Storm Overflow Programme

Q1 2023 Stantec supported YWS in SOAF Stage 1 root cause assessments at 173 STW which had met the investigation trigger based on EDM data for 2020 to 2022 inclusive.

The primary cause at 125 STW was hydraulic capacity during rainfall and 16 Asset Configuration.

Selection Criteria for Inclusion in AMP 7 Storm Overflows Programme.

• Solution needed to be able to be delivered within a maximum of 2 years, from concept to commissioning.
• CSOs which are exceeding the SOAF trigger spill counts will be targeted.
• Overflow count reduction benefits could be calculated with reasonable accuracy. A minimum reduction of 20% of discharge was required, but the aim was to reduce significantly beyond 20%.
• Primary cause was NOT an operational issue.
• Systems thinking was applied:
• The solution should be future-proofed, to consider any draft PR24 drivers.
• Benefits of potentially removing need for complex UMON4 drivers
• Consider the network and STW as a catchment – to avoid unanticipated upstream or downstream risks.