Environment officials closing in on culprits of river diesel spill

The net appears to be closing on those responsible for a diesel spill that polluted a 20km stretch of the Heathcote River in Christchurch, prompting a major clean-up and animal rescue operation.

More than 300 distressed ducks soaked in oily residue had been caught by last night and rescuers expected more.

At least 20 ducks had died in the 48 hours since the spill as the effects of hydrocarbon toxicity set in. All survivors were taken to the washing centre for treatment by expert marine oil spill specialists.

Environment Canterbury (ECan) regional council expects to be able to confirm the source of the spill today after inspectors spent most of Saturday tracing the leak to an industrial area in Wigram.

Interviews with industries in the area were expected to find who was responsible.

Between 5000 and 10,000 litres of diesel washed into the Heathcote River during the spill, although authorities doubted there would be long-term damage to the river's ecosystem.

ECan director of regulation Mike Freeman said yesterday the clean-up was "95 per cent complete". The final mopping-up was expected to be done by mid-week.

Eight oil booms were set across the river and teams of workers used wool absorbents to soak up the diesel.

Dr Freeman said about 10,000 litres of diesel was found by ECan staff in a sump near the Southern Motorway yesterday afternoon.

It was thought the fuel was washed from the sump into the river by rain on Friday.

If ECan prosecuted, those who spilled the diesel could face a fine of up to $200,000.

Christchurch-based Green MP Rod Donald, who lives close to the Heathcote River, encouraged ECan to prosecute.

"Whether this was deliberate or through carelessness they should prosecute ... they need to send a clear message to stop this type of catastrophe happening," he said.

Dr Freeman said a decision on whether to prosecute would be made after further investigation.

The response to the spill has been criticised by residents on the Heathcote River.

Kevin Fitzgibbon, whose property is next to the river, said he noticed the spill around 7pm on Friday night.

He said he tried to alert the authorities, but struggled to get hold of somebody.

Once he did, an ECan member came to his house promptly and placed two booms across the river there, but Mr Fitzgibbon said he did not see anyone again until Saturday evening.

Mr Fitzgibbon said had ECan been quicker to act it could have blocked the flow of the diesel much closer to the source.

He said with no cleaning centre set up until Saturday, he and others had to use their kitchen sinks to clean up to 40 ducks.

- NZPA