Investigations into poor water quality at Howrah Beach have progressed well over the second half of 2022. Previous analysis of bacteria levels in the beach sand, and groundwater at the old Wentworth Park tip site, reaffirmed the notion that stormwater is the primary contributor of contamination to the beach environment.
Between May and December 2022, 21 sewer leaks were found and fixed in Howrah. These were a mix of blockages and leaks caused by aging infrastructure.
Since stormwater investigations began in August 2021, 56 sewer leaks have been resolved in Howrah. TasWater have rectified 49 of these, with homeowners completing the rest. The result has been a notable decrease in bacteria levels being detected at the stormwater beach outfalls during dry weather. When a high bacteria level is detected, it now can be attributed to a specific event (i.e., sewer blockage), which makes finding and fixing it a quick process.
The successful approach to Howrah Beach investigations, and downgrading of the Bellerive West beach site from ‘Good’ to ‘Fair’, prompted similar investigations in Bellerive.
Between May and December 2022, 9 sewer leaks were found and fixed in Bellerive. Greater rainfall and stormwater flow in the past few months has resulted in contaminant dilution, making it difficult to detect and track. Bellerive will remain a focus area over the summer months.
Going into summer, the bottom of the stormwater catchments in Howrah and Bellerive are being monitored multiple times a week in order to detect changes in stormwater quality and ensure a swift response to any sewage contamination. All results to date highlight the importance of monitoring stormwater quality and the impact aging infrastructure has on public and environmental health.
In preparation of the 2022-23 recreational water quality (RWQ) season, council’s Environmental Health team commenced monitoring of both the beaches and stormwater outfalls early to ascertain the current state.
Results from November and the beginning of December have shown the waters at the beaches to be of good quality, except in the instances of heavy rainfall.
As outlined by the Department of Health and the Derwent Estuary Program (DEP), it is recommended that you do not swim at any beach in the estuary for at least 48 hours after a heavy rainfall event (>10 mm rain over a 24-hour period). Rainfall events such as these may result in a poor water quality reading, which affects the long-term grading of the beach.
We recommend keeping up to date with the DEP Beach Watch for weekly results here: Beach Watch | Derwent Estuary Program