Case Study

Witton Park, Blackburn

Donegan recently completed this project direct for United Utilities as part of the larger Blackburn UIDs scheme. The purpose of this project was to resolve the unsatisfactory intermittent discharge (UID) from the combined sewer network to the River Blakewater.

The solution will ensure that spill flows up to and including a 1 in 5 year return period are screened to a 6mm standard in two dimensions and will contribute to the River Quality Objective (RQO) for the River Blakewater.

Details

Client: United Utilities

Services Provided

Segmental Shaft Sinking

Tunnelling and Pipejacking

Scope of Works at Witton Park, Blackburn

The Civils scope works included the design and construction of a 20m internal diameter detention tank (stored volume in tank 4,500m3) complete with vac-flush central column to be self cleansing, RC Discharge chamber, RC Static screen chamber, 300mm diameter Outfall Sewer, modifications to an existing CSO chamber in Preston Old Road, 110m of 700mm diameter auger-bore, 4.00m diameter drive shaft for the installation of the auger-bore, 750mm diameter pipework from detention tank to River Blakewater (via new CSO chamber) and a reinforced concrete outfall structure.
The M&E scope of works included the design and installation of 1 No Isolation Penstock, 1 No 750mm diameter Flap Valve, 2 No Submersible Storm Return Pumps, 1 No submersible Scavenger Pump and 1 No tank flushing system; complete with vacuum pump, actuated valves, pressure and vacuum pipe, flushing column diaphragm valve assembly.