Tasmanian community environmental groups say the state’s new planning scheme will destroy their ability to influence planning decisions.

The State Government tabled a bill last week that seeks to enable the introduction of statewide planning rules.

A Planning Reform Taskforce has been set up to develop a single set of planning provisions that would replace dozens of separate existing planning schemes across Tasmania.

North East Bioregional Network (NEBN) president Todd Dudley says special local rules must be allowed.

“We're concerned that local provisions will become lowest common denominator standard, so any standard that's not widespread across Tasmania will be deleted,” he told ABC reporters.

It is part of the Liberal Government’s 2013 state election promise to create a single statewide planning system that is “fairer, faster, cheaper and simpler”.

The Local Government Association of Tasmania says it will rally against the proposed reduction in building assessment periods from 28 to 21 days, claiming its concerns have been ignored.

LGAT acting president Daryl Quilliam said the scheme appears to provide more streamlining potential, but it includes no changes to process requirements, so there is no guarantee of a faster or simpler outcome.

The chair of the Planning Reform Taskforce Mary Massina says streamlined planning would help all residents.

“It means a huge amount of benefit for mums and dads across Tasmania, because they will know how they can build their house, or deck or carport,” she said.

“This will actually fundamentally bring Tasmania's planning system from the worst, to the first.”

The Liberal Government is also seeking new laws that would allow the Planning Minister to use “call-in powers” over projects and “crack down” on third party appeals and “unreasonable” objections.

Jess Feehely, the state’s Environmental Defenders Office principal lawyer, said the proposals may face legal action.

“The devil will be in the detail and we'll need to see the scheme before we can say whether we're opposed to the scheme itself, but in principle there's no real problem with statewide consistency,” she told reporters.

“In relation to planning decisions ... having that decision making function rest with an independent body like the planning commission is the preference of the Environmental Defenders Office.”