CANNING RIVER — ECOSYSTEM HEALTH

Extract from uncorrected Hansard
[COUNCIL — Tuesday, 11 June 2013]
p17c-18a
Hon Lynn MacLaren; Hon Helen Morton


CANNING RIVER — ECOSYSTEM HEALTH
137. Hon LYNN MacLAREN to the minister representing the Minister for Environment:
(1) Given that the report “Ecosystem Health in the Canning River”, released by the Department of Water,
concludes that values of the river system are exposed to stresses from the developed catchment, does
the government have a strategy to reduce the pressures from sediment, nutrients and other
contaminants?
(2) If no to (1), why not?
(3) What measures has the government put in place to respond to the continuing or worsening stresses on
the system expected by reductions in rainfall predicted under even conservative climate change
scenarios?


Hon HELEN MORTON replied:
(1)–(3) The ecology of the Kent Street weir pool is important and I am advised that more than 30 species of
fish, crustaceans and tortoises were identified in the report to which the member refers. The fish
community as a whole has improved over the past five years. The report indicates that there appears to
be little risk to ecosystem or human health. However the environment directly around the weir is under
pressure due to a range of factors including periodic factors, including periodic salinity, declining
stream flow, nutrients and contaminants.

This government is committed to improving the rivers and a great deal is being done to improve this
section of the Canning River under the “Healthy Rivers Action Plan”. A number of large-scale artificial
wetlands to trap sediments and contaminants have been constructed along drains and waterways that
flow into this section of the Canning River, such as at Liege Street and Wharf Street in Cannington and
Anvil Way in Welshpool.
The importance of continuing in-river interventions such as oxygenation and the application of
Phoslock in the Kent Street Weir pool have also been confirmed through this study. The government is
investing $2.4 million in the upgrade of the two existing and ageing oxygenation plants at Bacon Street,
Wilson, and Camsell Way, Ferndale, and the construction of a new, third plant at Nicholson Road
Bridge in Ferndale.
Low rainfall and stream flow in recent years is placing additional stress on our rivers, including this
section of the Canning River. This is somewhat offset by augmenting stream flows in the Canning River
with additional scheme water during the drier months in accordance with the Canning River surface
water allocation plan. This latest report will help inform the management of Kent Street Weir during
years of low flow to ensure the freshwater environment upstream of the weir is protected and improved.