The water quality in Pottsville’s Mooball Creek is being monitored daily at multiple sites for dissolved oxygen, salinity and pH, and near the bridge, three times per week for bacteria and algae, owing to the creek mouth at Pottsville being completely closed by sand.
With the vast amount of sand on beaches at the moment, the beach has grown wider than the entrance walls and the whole lower estuary is full of sand.
Council continues to monitor sand movement and conditions in the creek, and water quality tests show water is still safe for swimming and health of aquatic life.
These daily tests have shown water in the lower estuary is consistently meeting water quality objectives for the protection of aquatic ecosystems and swimmer health.
Acting Director Community and Natural Resources, Jane Lofthouse, said the latest bacteria monitoring result is from Tuesday and is well within guidelines for safe swimming. ‘The creek is greener than usual, which is due to the growth of free floating single cell algae (phyto-plankton),’ said Ms Lofthouse. ‘The algae has also been assessed and is not a health risk. Dissolved oxygen and pH levels are well within guidelines for protection of aquatic ecosystems.’
Council is progressing relevant State Government permits to open the creek mouth so work can be undertaken if water quality monitoring confirms there is a problem, or suggests there are likely to be problems.
‘We are focused on ensuring any removal of the bar is effective in restoring tidal flushing, not just draining the creek, she said.
Ms Lofthouse says that community members considering digging a channel to attempt to open up the creek, are advised that NSW Department of Primary Industries Fisheries supports minimal interference with creek mouth sand barriers and advocates natural processes being allowed to operate to the greatest extent possible. ‘If not done properly and under the right conditions, there is a real possibility opening up the creek with machinery or by hand digging could make the problem worse.
This is because good quality water drained out of the lower estuary would be replaced by lower quality water presently sitting in the upper estuary and cane drains of Wooyung. This water is lower in dissolved oxygen and has a lower pH, and potentially higher bacteria levels.’
The maximum penalty for unauthorised works to open a closed estuary is $220,000 for Councils and $110,000 for individuals.
Water levels within the creek have now risen and continue to rise slightly due to overnight rain.
The need to put machinery onto the beach to undertake an artificial opening will be reassessed on Monday 15 October.
Avoid swimming in Mooball Creek at Pottsville
Bacteria levels elevated by rain and worsened by blocked creek
Council is recommending against swimming in Mooball Creek at Pottsville for the time being following recent and expected rain.
Council has been taking water samples from the creek in recent days to monitor bacteria levels while the creek mouth is blocked by sand.
Test results from one sample received today have revealed an elevated level of bacteria. Samples taken throughout the week had shown good to fair levels of bacteria.
Council’s Acting Director Community and Natural Resources, Jane Lofthouse, said while elevated bacteria levels didn’t necessarily indicate poor ecosystem health, swimming and other activities where water could enter the ears, eyes, nose, mouth and broken skin were best avoided.
‘Bacteria always increases in our coastal creeks after heavy rain due to urban and rural runoff, so it’s never advisable to swim at these times,’ said Ms Lofthouse. ‘But certainly given the lack of tidal flow in Mooball Creek, there’s no doubt the blockage has exacerbated the situation.
‘What’s happened today is that one water sample from one location has shown a result which is trending towards poor.
‘We need confirmation from a second sample to confirm the result but we won’t get that until tomorrow or Sunday, as the sample needs time to incubate. In the meantime, it’s safest not to swim in the creek, which is generally the case after rain.’
Council will continue to monitor water quality in Mooball Creek over the weekend and throughout next week and will advise when bacteria counts have returned to safe levels
At the same time, Council is progressing relevant State Government permits to open the creek mouth so work can be undertaken if required.
The need to put machinery onto the beach to undertake an artificial opening of the creek mouth will be reassessed on Monday 15 October.