Clyde public toilets empty into stormwater for 18 months

The Otago Regional Council is investigating after it was discovered late last week sewage from a block of public toilets in Clyde had been discharging into stormwater infrastructure since early last year.

Instead of hooking up to a wastewater main, sewer pipes from the Lodge Lane toilets had been incorrectly directed to a stormwater soak pit.

The plumbing error was revealed by chance last week during the course of construction works underway as part of a wider streetscape upgrade in the area.

Although details of exactly how things went wrong are still being worked through, Central Otago District Council, the owner of the assets, is confident human waste would not have been able to enter the nearby Clutha/Mata-Au River.

In a statement, CODC planning and infrastructure manager Louise van der Voort says the mistake was made early in 2023 when an existing septic tank was disestablished.

"This was when the connection (from the toilets) to the reticulated wastewater system was supposed to have happened but went to stormwater in error."

The stormwater soak pit is located underground at the Sunderland Street end of Lodge Lane.

Ms van der Voort describes it as a hole in the ground filled with free draining gravel, and designed to collect water, allowing it to gradually seep into the surrounding ground, reducing surface water and preventing ponding.

"The stormwater soak pit is not connected to the system that enters the river and as far as we are aware there has been no discharge to the river.

"This could only occur in the event there was an overflow of the soak pit causing water to travel down the kerb on Sunderland Street to a mud tank connected to the stormwater network.

"The soak pit manhole was initially sucked out to remove the contents, and a biological agent will be added to address any residual contamination."

Ms van der Voort says the council has followed procedure in notifying the Otago Regional Council of the incident.

The regional council has confirmed its staff are now investigating.

"While that investigation is underway we are unable to comment further," acting manager for compliance Simon Wilson says.

The toilets were closed for repairs on Thursday and reopened on Monday.

Main image (CODC): Human waste from the Lodge Lane public toilets has been piped into a stormwater soak pit since early 2023 and the mistake was discovered by chance on Thursday, August 29, 2024.