New approach to timing Wilson Inlet bar opening
Released 13 Oct 2009
The review of Wilson Inlet drainage practices addresses the issue of when to artificially breach the Wilson Inlet sandbar - a natural feature that separates the inlet from the Southern Ocean.
Department of Water Program Manager Chris Gunby said the review was required because the Environmental Protection Authority (EPA) decided in 2007 that the opening could have significant environmental impacts.
At that time, there were public concerns about the sandbar being artificially opened when inlet levels were lower than normal and the EPA recommended management agencies review opening practices.
The review, which involved considerable public participation, has broadened the range of factors to be considered in breaching the Inlet.
Water Corporation Great Southern Regional Business Manager David Hughes-Owen said that in the past the sandbar had been breached when the inlet reached a height of about one metre or when landowners advised that they are inconvenienced.
"Under the new management framework, the key factor will be protection of the inlet - particularly its aquatic flora and fringing vegetation," Mr Hughes-Owen said. "After that, a range of other considerations will be taken into account."
Mr Gunby said a key outcome of the review was consideration of opening the sandbar earlier in the season, rather than wait for a maximum inlet height to be reached.
"Leaving sandbar openings until later and later in the year can affect landowners greatly and result in very short opening durations," Mr Gunby said.
"The review has shown many of the benefits of an opening can be improved if an earlier, rather than simply higher, opening is used."
As well as considering environmental, economic and social matters, the review also considered site-specific factors such as ocean levels and tidal and weather patterns.
Mr Gunby said a decision-making tool had been developed to help planners decide the optimum time to open the sandbar.
"The decision-making tool is the first of its type in Western Australia," Mr Gunby said. "Its success will now depend on how it is implemented and we anticipate fine tuning as we learn from experience."
Copies of the review and new decision-making tool can be obtained from the Water Corporation or Department of Water.
For more information on the review contact Daniel Endacott on 9841 0102 and for more information on the decision-making tool contact Leith Phillips on 9842 4252.
Contact: Dianne Dixon
Phone: (08) 6364 6983 / 0419 910 847