Drinking water under threat, says Norman

Christchurch people need to "wake up" to the threat intensive agriculture poses to their drinking water, Green Party co-leader Russel Norman says.

Yesterday, Norman kayaked Lake Ellesmere, which has a toxic alga concentration, as part of his national "dirty rivers rafting tour".

He also attended a meeting on contaminated water supply in Dunsandel.

"It's Dunsandel today but it's Christchurch tomorrow – it's getting closer," he said. "It seems like it's a local problem for a little town but actually Christchurch needs to sit up and take notice."

A GNS scientist said last year a 200-metre deep well in Avonhead had shown a "statistically significant trend" in increasing nitrate-nitrogen concentrations since 1995.

At the time Environment Canterbury (ECan) said the trend was a concern but the concentrations were low and did not pose health risks.

Yesterday, Norman said central and regional government had a responsibility to introduce regulations that protected water supplies, lakes and rivers.

"We just have to accept that with this kind of intensive agriculture we need regulation," he said. "You can't say any more `farming's all right' – no-one has the right to pollute this water and this lake (Ellesmere) and fundamentally that's what happened."

Recreational fisherman John Rasmussen, of Southbridge, said he knew about the bloom and had no qualms about eating his freshly caught flounder.

"The commercial guys are still out fishing so there can't be anything wrong with it."

Medical officer of health Ramon Pink said gutted and cooked fish from the lake was safe to eat, but fishermen were still risking their health by being in contact with the water.

The Selwyn District Council said yesterday a $7000 ultraviolet radiation treatment system would be used to sterilise the E. coli in Dunsandel's water supply.

Some residents became sick because of unacceptable levels of faecal bacteria in untreated water from the town's well.

- © Fairfax NZ News