Derwent Estuary Program testing reveals river’s poor water quality

Blackmans Bay beach has reopened after retesting showed a significant improvement in the River Derwent’s water quality following faecal contamination. SEE WHICH BEACHES FAILED THE TESTING

The Kingborough Council is now warning against swimming at any part of Blackmans Bay beach after the latest water testing. Picture: SAM ROSEWARNE

UPDATED: Blackmans Bay beach has reopened after retesting showed a significant improvement in the River Derwent’s water quality.

Kingborough Mayor Dean Winter said the northern end of the beach had returned to good water quality following faecal contamination and was now safe for swimming.

“We are removing the advisory signs against swimming and are delighted that the water quality has returned good results,” he said.

“But the fact remains, there has been a major environmental incident here.

“These results show the contamination must be from an external source and we need to ascertain where it came from and where it has gone.

“Tasmanians only have a small window of warm weather to enjoy swimming in our waterways and they should feel safe and confident to do so.”

Cr Winter said the State Government needed to investigate the incident urgently.

He said the Council would extend its intensive testing regime for the rest of the summer and publish the results as soon as possible.

“I understand that some people in the community will have lost confidence in the water quality at Blackmans Bay Beach,” he said.

“We will do everything we can to restore confidence, but to do that we need to urgently find the cause of this week’s incident.”

EARLIER: Blackmans Bay beach has closed and other Hobart beaches face possible closure after water tests found elevated faecal contamination in the River Derwent.

Water tests conducted by the State Government-partnered Derwent Estuary Program on Thursday revealed beaches across the river were unsafe for swimming or needed retesting due to extremely high results.

As part of the program’s weekly testing, Hobart beach waters must return an entercocci reading less than 140 MPN (most probable number) per 100ml.

If a retest measures over 280 MPN the beach must be closed and the public notified. It can only be reopened following agreement between the Director of Public Health and a council officer.

Cousins Arabella Johns, 14, and Olivia Atchison, 7, of Blackmans Bay, went to swim at Blackmans Bay but ended up at Kingston Beach. Picture: NIKKI DAVIS-JONES

Seven of the 18 sites tested failed to receive a pass rating and Blackmans Bay recorded a staggering 9804, which Derwent Estuary Program chief executive Ursula Taylor said was the highest reading for Derwent waters she had seen.

“It’s certainly concerning to see such high results, no one wants to see that,” Ms Taylor said.

“We’re keen to work with councils and managers of TasWater to assist where we can.”

A TasWater spokesman confirmed the state utility was investigating to find the cause of the problem.

“TasWater is investigating possible sources which may have contributed to unfavourable water quality tests from Blackmans Bay Beach,” he said.

“So far no pipe breaks or blockages have been located or reported nor any abnormal discharges from treatment or pumping facilities in the Blackmans Bay area.”

In a Facebook post last month, TasWater advised of overflowing foaming treated wastewater from the Blackmans Bay Sewage Treatment Plant.

It comes after 10 million litres of treated but unchlorinated sewage poured for 24 hours into the Derwent off Macquarie Point on New Year’s Eve.

No swimming advice signs have been installed at Blackmans Bay Beach following unusually high water quality results. Retesting results are expected tomorrow. The Mayor is calling for urgent action on water quality across Derwent beaches https://t.co/Au2vOpSNPJ #BeachWatch

— Kingborough Council (@KingboroughTas) January 10, 2019

Kingborough Mayor Dean Winter denied the contamination was caused by the council’s stormwater outflow and said the problem rested with the State Government to fix.

“The readings at Blackmans Bay beach are astronomical and totally unacceptable,” he said.

“Kingborough Council tested its stormwater outflow at the same location, on the same day and found an extremely low reading.

“This points to external factors and these need to be investigated immediately.”

Cr Winter said Blackmans Bay beach would remain closed until further notice.

Hobart Lord Mayor Anna Reynolds said she was aware of the high readings at Sandy Bay’s Nutgrove Beach East (373 MPN) but directed the Mercury to Hobart City Council’s manager for environmental health Felicity Edwards.

“The protocol we’re following under public health guidelines is to re-sample — which we did on Thursday morning, and we will await the results before making any decision about Sandy Bay beach closures,” Mrs Edwards said.

Ariana Rivera, 11, and her cousin, Victoria Aburto, 11, both visiting from Sydney, at Sandy Bay’s Long Beach. Picture: NIKKI DAVIS-JONES

Clarence Mayor Doug Chipman also confirmed retests took place at Bellerive and Howrah beaches after poor test results were returned. Ald Chipman said any possible Eastern Shore beach closures would be made following the return of secondary results, and on the advice from the department of public health.

The six beaches that failed the water quality test and that will be retested are Nutgrove Beach (east), Hinsby Beach, Kingston Beach (north), Blackmans Bay (south), Bellerive Beach, Howrah (middle).

Beaches that received pass results are: New Norfolk (Fitzgerald Park), Windermere Bay Beach, Little Sandy Bay (south), Little Sandy Bay (north), Taroona Beach, Kingston Beach (mid), Kingston Beach (south), Howrah Beach (east), Howrah Beach (west) and Little Howrah Beach.