From the Members Survey 2021, most members agreed with the suggestion that “the Club should, if environmental regulations permit, keep ponds alongside the third fairway as full of water as possible throughout the year”.
The Club has a strategy to meet this objective, as part of an evolving Lake Management Plan. That Plan recognizes that the Club’s Groundwater Licence will almost certainly be cut by 10% in 2024, and probably more in future years. As a result, we are designing our new irrigation system to be more water efficient and taking other steps to enhance future water supply, not only for the ponds and the main Lake but also for the health of the local course environment.
As a first step, Course Superintendent Fraser Brown is currently trialing an evaporation control product ‘Waterguard’. It was first applied when the water level in the 3rd fairway ponds dropped below the spillway level in December 2021 and appears from visual inspections to have reduced loss from evaporation compared to recent years. A pump has been feeding water from the main lake basin to the ponds during January to bring the pond level back up to the spillway and another Waterguard treatment has been applied and will be monitored for effect before the Winter rains.
The Waterguard product is a harmless, odourless, transparent surface film that has been shown to reduce evaporation by around 50% on small dams and golf course waterbodies here in Australia and overseas. The trial is one result of recent hydrogeological studies and water balance modelling commissioned by the Club, which forecast that unless remedial measures such as evaporation control were implemented, then the larger pond next to the 3rd fairway would dry out most years. We saw this happen in 2020, not from leakage but mainly because of historically high evaporation rates, against a background of lower rainfall and a drop in the local groundwater table over the past 20 years. Recent geo-technical tests showed that the clay liner is fit for purpose but will degrade if it suffers repeated drying out.
These initiatives complement measures already taken by the Club to enhance water flows into Lake Karrinyup. These measures include the clearance every March/April of the Balcatta Branch Drain, which channels water from Careniup Swamp via the weir behind the third green, and which is by far the main source of water for our Lake. Also, the Club facilitated the work by the City of Stirling in early 2021 to enlarge the inlet drains and underground holding sumps that are now feeding greater volumes of stormwater into the pipe that runs under the 2nd fairway cross bunkers and into the lined lake fronting the 8th tee. And as part of the upgraded pipework to be installed for the new reticulation system, an overflow pipe leading from this lake to the lower ponds and/or the main lake basin will be installed to augment water levels before every Summer. In conjunction, the Club is assessing the installation of new water transfer pumps with solar panels.
Medium term, the Club will examine whether raising the height of the bunds which contain the water in the 3rd fairway ponds will help forestall water losses in early Summer. Longer term, the Lake Management Plan will assess the economic and environmental feasibility of constructing a Wastewater Treatment Plant. Potentially, such a Plant would take wastewater from the main Water Corporation pipeline that runs parallel to the 4th fairway and provide a reliable source of high grade treated water for the course and surrounds and for the main Lake and the ponds whenever needed. An assessment back in 2008 deemed it too costly, but technology has moved on and it could be the ultimate risk mitigation strategy for a declining water supply.
Chris Schrape – LKCC Course and Surrounds Sub-Committee
