A proposed ballot measure that would dedicate $100 billion to bolster California’s water supply is drawing a sharp rebuke, not only for the amount of spending but also for the dramatic sidesteps it would allow in the environmental review process.

For example, the proposal would make the controversial plan for a Huntington Beach desalination plant eligible for a huge taxpayer subsidy — even though the private, for-profit Poseidon Water company currently intends to pay for the $1.4 billion in construction costs.