Midland MLA Michelle Roberts said she would lobby Planning Minister John Day after meeting demonstrators on Sunday in front of the lake.
“Clearly the lake is a haven for wildlife, it’s a beautiful environment, and I was disturbed to hear about excessive development,” Ms Roberts said.
“I can’t see the need to fill in the lake, any development needs to be compatible, and I understand the area would have to be rezoned from rural to residential.”
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READ NOWMs Roberts said final decisions on rezoning are made by the West Australian Planning Commission, effectively the State Government.
Campaign organiser Sue McCann said Ms Roberts received a copy of the petition to table in Parliament.
The petition was signed by more than 880 residents.
The original petition was delivered to the Shire of Mundaring last Friday, the deadline for public submissions on the Helena Valley Road proposal.
Following consideration of the submissions is likely to be assessed in January.