If the water's brown don't go in
If the water is brown don’t go in. That’s the advice from Gisborne District Council.
It's more than 5 days since the emergency sewage discharge that happened during last week’s heavy rain event but people are not necessarily being advised to surf at city beaches or to paddle on city rivers.
Gisborne city rivers may be dirty for up to 5 days after heavy rain says regulatory services manager Sarwan Kumar. “From data collected we can see that people should stay out of the water at rivers and beaches for up to 5 days after heavy rain whether or not wastewater has been discharged.”
“It is not 5 days since it rained, and the rivers are still looking dirty. People are advised to make their own judgement call as to whether it is safe to swim or collect shellfish based on the look of the colour of the water."
“After previous storms we tested the water daily, and those tests showed the bacteria or faecal coliform levels gradually dropped away over a 5 day period. That is why we are satisfied, based on previous experience, that the health risks diminish over 5 days to the point the water in the rivers and city beaches is safe to use again."
Our rivers are dirty after heavy rain because our soils contain a large amount of sediment. The rain flushes sediment from the high country into our rivers along with agricultural and forestry waste.
Gisborne District Council was forced to make several emergency discharges of diluted wastewater, mixed with large amounts of stormwater into the rivers during the Tuesday-Thursday storm. The discharges are required because stormwater is getting into and overloading, the city’s wastewater pipe system. The extra stormwater in the system causes wastewater to back up onto people’s properties. When this happens, council has 2 options; open the valves and discharge into city rivers or allow the wastewater to back up through people’s toilets and overflow onto private properties and manholes on the roads.
Council immediately advises the public about the wastewater discharges, and issues warnings about using the rivers and beaches for recreation.
Warning signs were placed at more than a dozen locations along the rivers and the beaches pointing to the health risks.
Mr Kumar says there are no plans to test the water quality as this stage. Council will continue its regular cycle of water testing city rivers and beaches. The results can be viewed on our website
The warning signs put out after the storm will be removed when the water clears.