FACTS ABOUT THE IMPACT OF SEPTIC TANKS ON THE WATERWAYS OF THE PEEL REGION
- Rivers are a scarce commodity in WA, particularly on the Swan Coastal plain. The Murray still provides glimpses of the river environment it once was, but its condition is poor and worsening. The optimum potential of the Murray cannot be realised until it has been restored to ecological health. Affirmative action must be taken to address the environment problems of water quality, bank erosion and loss of landscape values. Ref.Draft Econ Dev & Rec Man Plan for Peel Waterways August 2002. Page 62.
- The major finding of this report is that the Peel waterways will not be able to sustain the increased recreational demands of expected population growth. Under such stress, the environment will decline further unless resources are found for action in the catchment to improve water quality throughout the system, and affirmative action to restore the environment and habitats of the rivers, particularly the Murray. Ref Draft Econ Dev & Rec Man Plan for Peel Waterways August 2002 Exec Summary Page 5
- The Murray River and its tributaries are listed on an international register of important wetland areas.Ref Media statement 14 th Nov 2004
- Evidence provided by the Health Department and WAWA proves that septic tanks are a cause of groundwater pollution of sufficient significance to warrant compulsory connection to the sewerage system. Ref Standing Committee On Constitutional Affairs and Statutes Revision In relation To A Petition Concerning Compulsory Connection To The Sewerage System 13 June 1996.This evidence is in conflict with an answer to a question on notice by Minister Griffiths 14 th of May 2003
- The concerns of the Shire of Murray re Bacteria levels of Enterococci and Presumptive Thermo tolerant Coli forms in the Murray River are such that the Shire as placed signs at strategic points along the river warning the public of the potential health risk involved when swimming in the river at any time of the year. Ref Shire of Murray Planning and Development Services Committee 21 Sept 2004.
- We have to get rid of septic tanks. Now we know a lot more about the effect septic tanks have on the environment. For instance, in the process of breaking down household wastewater, a septic tank and its leach drains allow a high volume nutrient rich liquid to return to the soil. Ref Water Corp Web Site 12/03/04.
- There are 238 houses on the banks of or within 500 metres of the Murray and serpentine Rivers that have access to reticulated sewerage and are not connected. Some of these properties have had access to the system since 1995 and the most recent being 2002. Based on Water Corp figures each of these properties leach an estimated 10.9 kgs of Nitrogen and 2.7 kgs of Phosphorous into the ground water and local waterways each year. This equates to 2594.2 or 2.5 tonnes of nitrogen and 642.6 kgs of Phosphorous. Most of these properties are in areas where the winter water table is 1 metre or less from the surface rendering the septic tank a health hazard (The depth to highest seasonal or permanent water table from the underside of a wastewater disposal system prescribed under regulation 49 of the Treatment of sewerage and Disposal of Effluent and Liquid Waste Regulations, shall be a minimum of 1.2 metres.Ref Water Corp Document, Parliamentary Committee Report 13 June 1996.News article West Australian 20 April 2005.
- Water Corp has the capacity to make these property owners connect to the sewerage system but have chosen not to do so.Ref Clause 58 of the Sewerage and Drainage act.
- In 2002 Water Corp used its powers to force a ratepayer to connect to the system but left the other 237 householders alone. Why? Ref letter to customer dated July 2002
- EPA 1990 Bulletin No 449 recommends that phosphorous should be spread at less than 15kg to the hectare in the Peel Harvey Catchment Area. Based on water corps figures septic tanks are leaching 21.6 kg of phosphorous and 87.2 kg of Nitrogen per hectare per year.Ref Department of Environment Presentation Peel Harvey Catchment Community Forum March 2005 .
- The area from Pinjarra to the mouth of the Murray and Serpentine Rivers has been identified as a nutrient hotspot by Department of Environment .Their computer modelling suggests the main culprit is seepage from septic tanks.Ref Dr Christian ZammitPeel Harvey Catchment Community Forum March 2005
- Conclusion -The Carpenter Government has committed $610,000.00 to protect the health of the rivers, esturies and waterways in the Peel- Harvey Region; however the patient is still connected to the poison being generated by septic tanks. Whilst the enforced connection and future provision of reticulated sewerage to areas around the Peel waterways will not be the final solution the challenges facing these waterways it will certainly make a major contribution towards the end result. In the initial stage there is no cost to the Govt as the sewerage system is already in place. All it requires is a whole-of –government approach and a will by the politicians to say that the Peel waterways are too important to let deteriorate any further. If the documents that support this summary are reliable then Water Corp has good reason to enforce clause 58 of the Act as a matter of urgency.