An extensive study of Perth’s groundwater has identified areas suitable for the sinking of additional garden bores.
Water Resources Minister John Kobelke said the Department of Water had drawn up a map of Perth’s groundwater from Two Rocks to Lake Clifton.
“There are about 160,000 existing garden bores in the Perth metropolitan area and the department has compiled extensive hydro-geological information, enabling the boundary between suitable and unsuitable areas for additional garden bores to be plotted,” Mr Kobelke said.
“In line with the areas identified in the groundwater map, waterwise rebates for new garden bores offered as part of the State-wide water efficiency measures will no longer apply in areas designated unsuitable from July 1.”
A number of factors were taken into account before determining which areas were unsuitable, including:
· salinity levels expected to be greater than 3,000ppm;
· proximity to river or ocean and possible ingress of saline groundwater;
· proximity to conservation wetlands;
· potential for unreliable supply due to clay soils or crystalline rock; and
· potential for development of acid sulphate soils.
“The boundary has been drawn to best fit property parameters and roads to ease decision-making about eligibility for the rebate on the cost of installing a garden bore,” the Minister said.
“People wishing to install a new garden bore outside identified suitable areas will still be able to. However, the Government will not help fund what has been identified as a bad investment.”
Since October 1, 2007, garden bores in the Perth metropolitan area have been restricted to watering three days per week between 6pm and 9am, as part of the new efficiency measures.
“The current watering rosters have led to a substantial reduction in the average scheme water usage across the Perth metropolitan area and people do not need to use as much to keep their garden thriving,” Mr Kobelke said.
Due to the varied parameters impacting on suitability, the areas identified as suitable or unsuitable do not follow suburb boundaries. A list of suburbs which are entirely suitable or unsuitable for a garden bore is attached.
For suburbs containing both suitable and unsuitable areas (also attached), the Water Corporation Waterwise Helpline - 131 039 is able to advise whether a property is eligible for a garden bore rebate.
The start of the next financial year was chosen as the rebate cut-off for unsuitable areas, to enable the bore drilling industry to complete existing arrangements with minimal impact.
Minister's Office - 9222 9211