P lab run-off hurting sewage treatment plants

BY ANDREA O'NEIL
Last updated 11:18 05/02/2013

Relevant offers

Kapi-Mana News

Residents warned of dust and noise as work on Transmission Gully link begins Hundreds gather to help kindy, suffer the pain of a thousand knives in bodies at Plimmerton midwinter swim It takes a community to build a canoe: Porirua helps keep a promise Fire brigade battle scrub fire near Porirua Station Porirua residential rates increase set at an average 4.5 per cent Wellington police looking for Taylor Ellen Newbery Porirua car thieves often want a ride - and not much else Funding coming in as Porirua City Council backs free school bus for another year Porirua railway station set to get much-needed car park expansion NZ Community Trust boosts local club to the tune of $15,000

Illegal drugs cause harm in many ways, including killing Porirua's sewage treatment plant two years ago.

In 2011 chemicals from a Tawa P lab were dumped into the sewage system about the time of a police raid, says Peter Bailey, Porirua City Council's general manager of asset management and operations.

The chemicals ended up in the council's Titahi Bay sewage treatment plant, where they killed much of the beneficial bacteria that breaks sewage down.

"It's like using Roundup on your vege garden, in a way."

As a result, both the harmful chemical and untreated sewage flowed into the sea, Mr Bailey says.

There was no way to contain the untreated sewage. "The volume is so great there's nothing we can do. It would be a massive job to store it in holding tanks."

The plant treats all of Porirua's sewage and much of north Wellington's, servicing 70,000 people in all.

Its size works in its favour when illegal chemicals are dumped - the huge volume of water flowing through the plant dilutes the chemicals, making them less harmful both to the ocean and to waste plant staff, Mr Bailey says.

Smaller cities are not so lucky and unwanted chemical buildup in small plants can cause explosions.

The P lab incident was the third chemical kill-off in a decade, but usually the culprit is a business illegally dumping industrial chemicals into the system.

Firms can legally dump chemicals in Seaview, Lower Hutt, but there is a steep fee to do so, Mr Bailey says.

Ad Feedback

- Kapi-Mana News

Comments

Special offers

Featured Promotions

Sponsored Content