Building an Ocean Outfall

Around 2007 the Christchurch City Council is going to build a pipeline out to sea, called an Ocean Outfall, to discharge the city’s treated wastewater. It is
expected to be completed around 2009, depending on how long the planning and consents process takes.

Water quality and beach standards The City Council has recently received results from ocean current modelling, which are confirming its expectations of the standard of water that will be reached once the Ocean Outfall is operating.

“The public needs to know that taking the city’s treated wastewater discharge out of the estuary and piping it out to the ocean will help improve Christchurch beaches,” says City Council city water and waste manager Mike Stockwell. “Moving the outfall to sea will make a significant improvement in the estuary. In addition, all beaches from New
Brighton to Scarborough and those inside the estuary are expected to be rated “Good” once the major sewer upgrades are finished and the Ocean Outfall is operating,” he says.

At the moment, using the national grading system, all the beaches in the Avon-Heathcote Estuary and those from the estuary mouth to Scarborough are rated “Poor” at best.

• A public consultation process on water quality and beach standards closed on 31 March, 2004.
• The City Council is expected to make a decision in August about the length of the pipeline, which will be at least 2km long, and whether to include a UV disinfection plant.
• For information see www.ccc.govt.nz/oceanoutfall