High pollution levels at three swimming locations have marred an otherwise good report card for water quality at beaches and baths in St George and Sutherland Shire.
The 2017-18 State of the Beaches report rated all ocean and estuarine locations in the region the same as in 2016-17 with one exception.
Horderns Beach at Bundeena improved from Poor to Good.
Pollution levels at Oatley Bay baths, Carss Point baths and Gymea Bay baths showed no improvement on the previous year’s rating of Poor.
All ocean beaches and baths between Greenhills and Oak Park received a Very Good rating, while Boat Harbour was rated Good.
In Botany Bay and the lower Georges River, a Good rating was awarded to Silver Beach, Como baths, Jewfish Bay baths, and all baths between Sandringham and Kyeemagh.
In Port Hacking, Jibbon Beach, Horderns Beach, Lilli Pilli baths and Gunnamatta Bay baths were rated Good.
“Rainfall is the major driver of pollution to recreational waters, generating stormwater runoff and triggering discharges from the wastewater treatment and transport systems,” the report said.
“Changes in rainfall patterns are reflected in beach water quality over time due to variation in the frequency and extent of stormwater and wastewater inputs.
“The Beach Suitability Grades for 2017–2018 are based on water quality data collected over the last two to four years.
“Rainfall over this period has been diverse, beginning in 2014 with a very wet year for the coast, followed by mostly variable rainfall with some significant storm events, some extended dry periods and significant wet weather events.
The situation for each year was:
- 2014–2015: wet summer with above average rainfall, particularly on the coast.
- 2015–2016: wet summer, with well above average rainfall during January, including heavy rain and flooding in coastal areas
- 2016–2017: the wettest March on record for many coastal areas and intense storm activity over summer.
- 2017–2018: prolonged dry periods broken by heavy rain at times, including widespread rainfall along the NSW coast in the last week of summer.
- Very heavy rainfall impacted much of the NSW coastline between 8 and 14 June 2017. This was followed by a period of average to below-average rainfall, with dry conditions continuing through to April 2018.