Bournemouth Coastal Interceptor Sewer Structural Repairs
The Bournemouth Costal Interceptor Sewer tunnel (CIS) runs between central Bournemouth and Holdenhurst Sewage Treatment Works and is the main trunk sewer serving a population of up 180,000. The CIS was constructed in the late 1960’s with the purpose to divert all flows away from historic sea outfalls to Bournemouth Bay to the newly constructed Holdenhurst STW on the town outskirts. Minimum flows are in the region of 300l/s in dry weather and in storm conditions the CIS provides attenuation and regularly surcharges significantly above crown levels. Flows into Holdenhurst STW from the CIS can exceed 2500l/s in storm conditions.