Sewerage is once more flowing out of the system through the manholes at Black Beach.

"As far as I know, Sydney Water hasn't got in touch with Council since the last time it happened," says Councillor Andrew Sloan, a water engineer.

"The situation has clearly become urgent, and we need Sydney Water to undertake an Overflow Abatement Strategy for this catchment.

"We need them to take Kiama just as seriously as they are Lake Illawarra, where such a Strategy is being undertaken."

Sydney Water has been approached for comment.

The water continues to bubble up from the sewerage system

An eyewitness said at 9am he saw the manhole bubbling up, and then spectacularly cascading over the wall into the harbour in a big brown waterfall.

Our photos, taken at 11am, show Council has zoned off the area, but Sydney Water has yet to arrive. Last time it happened, in late March, the cleanup took over a week.

Kiama Council has advised residents and visitors to avoid swimming at our beaches and rock pools during and immediately after heavy rainfall due to the risk of stormwater pollution.