The NSW Government has scrapped the body tasked with protecting the environment and heritage.

The state’s Office of Environment and Heritage (OEH) will cease to be a stand-alone independent body, with the environment portion to be absorbed into a new planning and industry department, while heritage will be moved into the department of premier and cabinet.

The OEH provided scientific evidence and advice on major developments and national park and reserves, while also running a range of conservation efforts.

Critics say the moves are designed to directly benefit developers, while public servants have told reporters that it could mean more projects with potential negative environmental impacts are approved.

Premier Gladys Berejiklian defended the changes, saying “the Environment Protection Authority is still there”.

“When you've got a new government it's the time to make sure you make those changes that provide a better outcome for the people of this great state,” she told reporters in Sydney.

The Nature Conservation Council says NSW has lost the ability to stand up to miners and developers.

“The decision to downgrade the environment portfolio and subsume it into a super-ministry with industry and development is par for the course from a government that has been at war with nature and environmental protection since it came to power in 2011,” chief executive Kate Smolski said in a statement.

The NSW Government has also announced the appointment of Nationals MP Melinda Pavey to the water portfolio.

Ms Pavey replaces Niall Blair, who left the regional water portfolio after massive fish kills in the Murray-Darling river system.

Ms Blair was also the state’s agriculture minister and will be replaced in that role by Nationals MP Adam Marshall.

NSW deputy premier John Barilaro said separating water and agriculture “allows us to focus on each of them particularly with a greater focus on the drought but more importantly on water”.