A new groundwater plan aimed at reducing the effects of climate change on Perth's water resources has sparked the ire of some experts.
WA's Water Minister Dave Kelly announced the new Gnangara groundwater plan and a garden bore sprinkler roster to reduce water usage on Friday.
Households with a garden bore in the Perth and Peel regions have until September 1 to prepare for a new sprinkler schedule that limits the use of bores to twice a week.
The plan also gives large, licensed water users north of the Swan River, including industry, irrigators and local governments, six years to reduce their groundwater usage by 10 per cent.
The Water Corporation vowed in a statement to reduce groundwater abstraction by 27 per cent by the 2028 deadline.
Some industries, including schools, hospitals and commercial nurseries, are exempt from the reduction.
'Time is not on our side': Water Minister
In a statement, Mr Kelly said the plan would minimise the impact of climate change.
"By everyone making small changes to how they use groundwater, we can deliver environmental benefits, provide industry with clarity and certainty and protect this precious resource for future generations," he said.
Mr Kelly said there was no option but to act quickly.
"Time is not on our side. We need to make changes and that is why this plan does make some significant changes. But if we implement them, we can still have a green, liveable city."
'I think there's an imbalance': Hydrogeologist
Perth-based hydrogeologist Ian Hunt said the beginning of Spring was too soon to expect households to prepare for the change.
"If you look at the other bigger users, that's almost six years into the future.
"I think there's an imbalance. Stopping the garden bore users is easy and quick, but I don't think it addresses the problem."
Mr Hunt claimed the state government was tiptoeing around some of the glaring issues with water supply.
If you think it won't affect you, 'it bloody well is': Gardening expert
Horticulturalist Sabrina Hahn told ABC Radio Perth that the move would see a huge increase in hand watering and would also have a massive effect on urban heating.
"Can Water Corp, who of course stands to gain enormous amounts of revenue from people switching over to hand watering, can it cope with this big increase?"
Ms Hahn said the move would reduce the number of gardens across Perth.
"People are going to go, 'oh we can't water the garden, let's not have one, or we'll put succulents or cacti in.'
"That's going to have a massive effect on urban heating."
Ms Hahn said in five years, 50 per cent of the existing garden would be built over, and the knock-on effect of urban heating would impact people living in the city.
Ms Hahn said WA's peak amenity horticulture body proposed a voluntary bore registration plan, allowing registered properties to run their sprinklers three times a week.
She said the industry received feedback the plan was too difficult.
Wetlands must be protected
Michael Hammond from the Department of Water and Environmental Regulation said the plan was vital to protect Perth's groundwater.
"Our groundwater-dependent ecosystems are some of the most biologically diverse and ecologically significant parts of our landscape and they also support most of our wildlife," he said.
Mr Hammond said Perth had lost around 80 per cent of its wetlands over the last 200 years due to development.
"Those remaining wetlands we have are really worth protecting, and that's a big part of this plan."
