Developers say this week’s 20 per cent rise in metropolitan open space contribution to $5500, which traditionally flags a similar rise in land taxes, is an impediment to affordable housing.

“In these times there is no need to have open space contribution to purchase land, especially when we could be reducing the cost of land by $5500,” surveyor Richard Abbott said.

The open space contribution scheme was originally conceived to guard against over-development. It is paid by developers in lieu of leaving open space in housing estates.

The money is then distributed by government to local councils so councils can buy open-space land like parks.

SA Urban Development Institute spokesperson Terry Walsh questions the scheme’s validity.

“There is doubt in many people’s minds whether the money is actually spent on open-space contributions,” Mr Walsh said.

Mr Abbott said open space was one example of government regulations pushing up housing costs because it made land more expensive.

He said land tax, slow approval processes and government failure to release publicly owned land for subdivisions were also factors.

“It is expensive to acquire land. There is so much land owned by government and they trickle it out when they want to and change the zoning, and that increases the price.

“I believe the cost of land development and affordable housing has become an extremely complex dilemma for government to resolve.”

The increase in open-space contribution comes while the Government continues affordable housing policies such as a stipulation which reserves 15 per cent of all major developments for affordable housing.