I swim regular and note significant increasing of smelly foam trail stretching around Curl Curl to Dee Why beach. Before it happened only during heavy rain. Since Xmas it appears every morning around 7-8am and stays all day. I have had ear infection and heard there is increase of visits do doctors for similar reasons in area.
Looking for explanation interesting facts are found.
During periods of rain, water seeps into the mains through sewerage joints (the pipes are only butted together). Full of diluted water, sewage cannot carry the volume. To avoid the sewage «backing up» in the pipes, overflow outlets have been designed and built into the system and the diluted sewage overflows into creeks, gutters storm water canals, lagoons, beaches and surf. This is the reason why the public are advised not to surf for 3 days after heavy rain — to give the overflows time to flow away, degrade and their content of bacteria, viruses etc. to decompose.
Sydney Water’s says :In wet weather, stormwater flows into the sewerage system and may exceed the system’s capacity and result in overflows from our pipe network and/or the diversion (bypassing) of one or more process units at the treatment plant. These events are recognised within the Environment Protection Licences set by Department of Environment and Conservation (NSW).
At the same time: In dry weather, overflows of sewage can occur for many reasons. For instance, when there is a blockage in a sewerage pipe caused by tree roots or other material, or if a pump fails at a pumping station. At treatment plants, bypasses may result from a power failure. Sydney Water provides notification of overflows or bypasses
1.According Sydney Water there were no overflows since last year. It is not corresponding to a look and smell of the water around Curl Curl — Dee Why.
2. It is not clear whether they measure water quality in this area at all. Possibly, they measure water directly near sewer plant when is operating. Possibly, the is no water quality control near overflow outlets and especially during emergency outflows lasting over a moth now!
Would be nice to know opinion of other residents. Sewerage is difficult problem to solve but at least we should see a map of sewerage overflows in an area, they capacity and time of activity.
How many sewage storage tunnels would be needed to keep sewage overflows out of Manly, Curl Curl, Dee Why and Narrabeen lagoons and out of gutters and storm water pipes which discharge directly to beach and surf?