The Waikato River has had a cleanup through the city to remove big logs and other water hazards which had built up over time.
One of the biggest blockages was a log over 30 metres long wedged against the Fairfield Bridge, trapping other debris such as plastic bottles and other discarded rubbish.
Environment Waikato Navigation Safety Officer Bill Cameron said some of the logs and stumps which had fallen into the river had been there for a very long time.
They were pulled out by a barge operated by Warren Arnet over several days, and taken to river beaches to be cut up and disposed of.
“We were surprised at the number of logs – and at the plume of trapped pollution which was freed as they were taken away. Many small objects had been trapped on the branches and they just washed away as the logs came out.”
The largest log had been identified with buoys on Christmas Eve so it could be navigated by boats until it could be removed safely. It was blocking a third of one river channel and a quarter of another, and a kayaker had snagged on it recently.
At least 10 large logs were removed, along with loops of thick industrial wire, which had been under water for years.
New navigation safety signs had also been placed along the river – but one of the expensive signs had already been vandalised, he said. This type of vandalism meant people using the river might not be able to identify sunken objects or structures.
Mr Cameron said logs and other debris were a problem throughout the river, but became hazardous through the city where the river narrowed.