"These proposals would significantly shift the balance of power between national and local government ... allowing central government much more latitude to delve into local affairs," the association says in a submission on the reform. A Government discussion paper says it should have power to direct plan changes in some circumstances, including specifying the outcomes to be achieved.
The EMA is also worried about proposals to rewrite the act's core principles which guide decision-making by the courts and councils.
The Government plans new clauses on infrastructure and land availability and wants all principles to have equal footing, so none receives greater weight.
EMA executive officer Peter Atkinson says ending the current hierarchy of principles "could open the whole thing up again to litigation".
Environmental groups have expressed similar fears. Forest and Bird advocacy manager Kevin Hackwell says the changes will make it harder to stop developments such as water storage or coal mining in areas with high ecological values, while ministerial intervention could see environmentally sound decisions overturned.
Other proposals would limit opportunities for objections and narrow the scope for appeals.
One key matter proposed for deletion is amenity values - a term which, in urban areas, helps ensure higher density development comes with good design and open space and relates to surrounding neighbourhoods. Experienced planners say removing amenity values from the core principles could lead to less sympathetic development.
"The fact that it's there gives the council a basis to have strong policies around things like sunlight, site density, access to recreation and traffic volumes," planning consultant Hugh Jarvis told the Weekend Herald.
Removing amenity values may be linked to the push for affordable housing, Mr Jarvis said. The Government is rushing through legislation to declare special housing areas in Auckland with fast-tracked consenting and limited appeal rights. Housing Minister Nick Smith has warned that Aucklanders may need to sacrifice quality for affordability.
"It's as if they see housing as simply a roof over people's heads whereas amenity provides for people's mental and social wellbeing," Mr Jarvis said.
Environment Minister Amy Adams says amenity values can be provided for with more explicit district plan rules. She says the act's core principles tilt the balance too much in favour of environmental protection and reforms are needed to end 22 years of delays and increased costs.