Rainfall will be nationalised this week when the Water Amendment Bill 2008 returns to the House of Representatives from the Senate.

Labor has adopted the previous Liberal Government’s flawed policy that the right to use rain that falls on a person’s roof is vested in state Governments by state legislation. The Bill refers states’ constitutional powers in relation to water to the federal Government.

Under the policy, “entitlement regimes” will be imposed in order to regulate a person’s use of a rainwater tank. An entitlement regime of 50%, for example, would double the cost of rainwater.

Few Australian households currently use rainwater because of cost. But Australians are most likely to voluntarily install rainwater tanks when the cost per kilolitre of rainwater is less than mains water. Low cost rainwater is achieved by economies of scale in manufacturing and installation. A national rainwater tank program will deliver rainwater at a lower cost than mains water, for the 80% of houses in Australia that currently do not have tanks (90% in capital cities). About 4.5 million houses do not have rainwater tanks.

Nearly $1billion is currently being spent by state and federal Governments on subsidies for rainwater tanks and associated equipment, such as pumps, valves and plumbing. Subsidies that underwrite high cost manufacturing and installation are a waste of taxpayers’ money. Every household can have their own low cost rainwater harvesting system within 10 years provided the investment is made in manufacturing equipment by the private sector, at no cost to Government, and without subsidy.

The federal Government is unwilling to name legislation which allegedly vests the right to use rain that falls on a person’s roof in the relevant state Government. The explanation is simple: no legislation supports the previous federal Government’s claim, as detailed by the former Minister for the Environment and Water Resources, the Hon Malcolm Turnbull, in his reply to Question On Notice No.2971 in the Senate on 9 August 2007.

No state Government claims that the right to use rain is vested in them.

The NSW Government confirms that a person asserts their right to own rainwater by installing a rainwater tank. Under Victorian Government policy, water that falls on a person’s roof is the property of that person.

The law in Queensland is that the right to use water collected from roofs for rainwater tanks is not vested in the state Government. And, the South Australian Government says, “any rain that becomes runoff from roofs is surface water” where “runoff” means water that flows from a catchment area into streams, lakes, rivers or reservoirs. Rainwater tanks, obviously, prevent rain from becoming runoff, or surface water.

Under each state’s legislation, the right to use surface water is vested in the state Government. Water that flows over a person’s land after having fallen as rain is surface water. By definition, surface water is not captured and controlled.

Rainwater supplied to a rainwater tank from the roof of a building is not surface water because the roof of a building is not land; and, rainfall is legally captured and taken under a person’s control by means of that person’s roof.

The Bill is “informed by, and progresses” the National Water Initiative Agreement 2004 (NWI). According to the federal Government, clause 2 of the NWI is a reference to state legislation that vests the right to use rain that falls on a person’s roof in the relevant state Government.

The NSW Government confirms that clause 2 of the NWI is in error, while the Victorian Government points out that clause 2 does not say “all” water in Australia is vested in governments.

The legal interpretation of state water legislation is a matter for the federal parliament by virtue of the Bill. The current federal Government is obliged to prove the claim made by the previous federal Government, or repudiate it.