A new waste water treatment plant is required to continue to effectively drain and treat the waste water, sludge and liquid imports arising from the Cambridge catchment in a similar integrated process that meets the required regulatory and environmental standards.

Early design assumptions have been made to identify land area requirements. These assumptions are based upon the connected population equivalent (PE) that needs to be served, together with an element of growth, full flow to treatment, storm storage and the integrated sludge treatment process. The early design assumptions are also based upon a process capable of meeting the current Environment Agency’s Permit Standards.

The capacity to deal with the waste water from the Cambridge catchment (together with an element of growth) and the capacity for the integrated STC, equates to a PE of 548,000. The requirement is, therefore, for a waste water treatment plant with a total overall PE in excess of 500,000. The land requirement for a new waste water treatment plant to treat in excess of 500,000 PE would be in the region of 22 hectares, not including road access to the site or any necessary landscaping or other mitigating requirements.

The new site area also needs to accommodate the necessary connecting infrastructure which includes, but is not limited to, the following.

  • A new drive shaft to enable a connecting tunnel back to the WWTP. On completion, the shaft would be retrofitted as the new terminal pumping station.
  • A new final effluent tunnel/pipeline from the new site to an outfall into the River Cam.
  • Connecting infrastructure for Waterbeach.
  • The potential to divert and connect any existing assets which would aid to the operational efficiency of the scheme.