Cambridge Wastewater Treatment Plant Inlet Screen Installation

Waipa District Council required the installation of a Principal supplied drum screen into the raw water inlet channel at Cambridge WWTP, along with a new screw press, and all associated wash water, electrical and control services to service these plant items.

The project scope included:

• Managing bypass flows while modifying the screen channel whilst ensuring the work area is kept free of wastewater flows for the duration of the works.

• Construction of new reinforced concrete walls and floor slabs for Suboscreen and for Overflow channel and Bypass chamber.

• Demolition of existing walls, refurbishment of impacted concrete surfaces and reinforcing

• Construct reinforced concrete plinths for new Wash press.

• Construct high level overflow from channel upstream of the Suboscreen, to connect to a new 1650 diameter manhole to be installed over the existing DN 525 concrete bypass pipelines.

• Design and install electrical works necessary to service the Suboscreen, Wash Press and flowmeter.

• Collaboration with Suboscreen and Wash press equipment supplier (Brickhouse).

• Prepare functional description then programming for controls and SCADA update, to operate all the new equipment including supply and installation of all cabling, ducting and fixings as required.

• Installation of Principal supplied Suboscreen, Wash press and launder channel.

• Carried out pre-commission testing, then commission with assistance of Suboscreen and Wash Press supplier (Brickhouse).

• Connect to existing DN 63 PE 100 river water supply main to the existing river water tank at the inlet works.

• Supply and install new DN 80 semi-automatic raw water filter in the raw water line immediately upstream of the river water tank.

• Supply and install wash water supply to the Suboscreen and Wash Press from the river water tank.

• Supply and install new Krohne Tidalflux DN 500 partially filled electromagnetic flowmeter into DN 600 concrete gravity inlet pipeline, including PE 100 pipework transitions upstream and downstream of the new flowmeter, and new penetration into inlet works.