Home Your environment Coasts, Catchments & Creeks

Printer friendly version

Tillegerry Creek

Update 1 - 24/10/2005

In July this year the NSW Food Authority detected human viruses in oysters collected from oyster harvesting Zone 5B of Tilligerry Creek.

This led to the indefinite closure of this part of the creek for oyster harvesting, affecting fourteen oyster farmers.

Water quality monitoring has revealed that septic tanks within the high water table area of Salt Ash and Bobs Farm are the primary source for human faecal pollution entering local drains and Tilligerry Creek. Further research undertaken by the University of Newcastle and the CSIRO supports this view.

How does this affect people living in the area?

The pollution of Tilligerry Creek is not just a problem for oyster farmers. If left unaddressed it could lead to significant public health risks and further restrictions on fishing, boating, swimming and other uses of the creek. This in turn could have negative impacts on local businesses, tourism and the economy.

Unfortunately, it also means that most septic tanks in the Salt Ash and Bobs Farm area will need to be upgraded over the next two years, with visibly failing systems requiring urgent attention.

What’s the urgency?

Recent water quality testing within the top reaches of Tilligerry Creek has indicated the level of pollution is increasing.

If not stopped, pollution could spread to the entire lower reaches of the creek and lead to the closure of other oyster harvesting areas and adjacent swimming areas. The collection of all shellfish from the creek could also be banned.

What’s the solution?

Port Stephens Council has been working closely with the NSW Premiers Department and other government bodies to come up with the most appropriate solution to this problem.

The best solution in the long-term is probably the installation of a conventional sewage system in the Salt Ash and Bobs Farm area. This option is currently being investigated by the State Government, however, installation would take at least 10 to 15 years with the potential cost to owners ranging between $40,000 and $50,000 per property.

There is also no guarantee a conventional sewage system will ever be installed by the State Government in this area.

The only real solution, therefore, is for most existing septic systems within the Salt Ash and Bobs Farm area to be upgraded.

A number of upgrade options were considered including:

• Upgrading existing septic systems to a mini treatment plant with disinfection and mound (the minimum requirement for new properties in areas of high ground water). This would have cost owners between $16,000 - $20,000 per property
• Requiring owners to install a pump out system at a cost of approximately $5,000 for installation, with ongoing costs of around $3,000 per year to pump out the waste
• Upgrading existing septic systems to the ‘Wisconsin Mound System’ at a cost to owners of between $5,000 - $9,000 for installation.

The Australian standard (AS1547:2000) for domestic onsite wastewater systems recommends mound type systems for high ground water table areas. While the mini treatment plant offers the most complete short-term solution to the Tilligerry Creek problem, the Wisconsin Mound System was chosen because it is the most affordable and effective option for property owners and can be installed quickly.

What do people living in the area have to do now?

Council’s Wastewater Management Officers are currently inspecting all of the 470 septic systems in the Salt Ash and Bobs Farm area and issuing upgrade notices as required. This task will be completed by November this year.

If a septic system is identified as a ‘failing system’ it will need to upgraded by the date specified as outlined in Council’s Order. In most cases this will involve the installation of a Wisconsin mound.

If a septic system has not been identified as failing, but is located within the Tilligerry Creek catchment area, it will need to be upgraded to a Wisconsin mound system as per the council notification.

What is Council doing?

Council is installing pollution traps in some of the most affected areas, especially the top end of the Salt Ash drainage system, to minimize the transport of bacteria and viruses into Tilligerry Creek. Council is also conducting further water quality monitoring to determine the full extent of contamination of other local waterways.

Council is also holding information days at Salt Ash Community Hall, 1 Michael Drive Salt Ash, on Friday 4 and Saturday 5 November, between 10am and 2pm. People are encouraged to attend on one of these days to find out more about this issue and ask any questions they might have.

What happens if people who have been advised to upgrade their septic system don’t do anything?

Under the Local Government Act (1993) Port Stephens Council has the power to request property owners to upgrade their septic system. Owners who fail to upgrade their systems within the specified time period may be subject to fine(s) and/or legal action.

Where can people get more information?

You can obtain further information by telephoning the Environmental Services Unit of Port Stephens Council on 4980 0164.

Contact details
Environmental Services Unit
02 49800164 (ph)
environment@portstephens.nsw.gov.au

© 2008 Port Stephens Council
This page: http://portstephens.local-e.nsw.gov.au/environment/1273/44035.html