Three hundred jobs are expected to be removed at the Department of the Environment over the next four years.
Spending pressures could force the relocation of staff and offering of early retirement and voluntary redundancies, a consultation document from the department said. Some of the reductions have already been announced.
Road safety grants are among programmes facing reduced spending.
The department has to save £15.4 million next year. A shortfall in planning income has also affected finances.
Some expenditure on environmental programmes like the repatriation of illegally dumped waste to the Irish Republic and wider anti-flytipping measures will be postponed because £4 million a year has been removed from the department's budget instead of expected plastic bag tax receipts.
All government offices are under pressure to make savings over the 2011-2015 budgetary period following last autumn's Comprehensive Spending Review which cut the Northern Ireland grant from Westminster.
Today's consultation said: "We anticipate that the further reductions in expenditure anticipated in the Executive's Draft Budget will create a need to further reduce the number of posts within the department by some 150 jobs.
"When combined with the 150 posts still to be removed from the department, the overall requirement for workforce reductions within the department over the budget period will be some 300 posts, with most of these reductions happening over the next 12 to 18 months."
Planning Service, the Northern Ireland Environment Agency and grants for road safety are all to face cuts.
There will be a cessation of grants towards funding for the acquisition of listed buildings at risk and a suspension of a systematic second survey of buildings of historic and architectural interest.
There will be a reduction in proactive pollution prevention and there will also be a decrease in the value of local road safety grants as well as the amount available for road safety advertising.
The document said: "Although some recruitment of additional enforcement staff will still be possible, the proposed restriction on recruitment will constrain the Driver and Vehicle Agency's ability to reduce the high level of non-compliance within the goods vehicle, taxi and bus industries."
On Monday the Department for Employment and Learning outlined £67 million of cuts.
The department plans to freeze the cost of living increases for staff with salaries over £21,000. It also aims to save £4 million through staff efficiencies.
The Minister for Employment and Learning, Danny Kennedy, described his budget as "extremely challenging".
In the budget announced by Finance Minister Sammy Wilson it was decided that education would lose £67 million, compared to losses of £63 million for regional development and £48 million for the Department of Justice.