Councillors commented it would be difficult planning 10 years ahead when the government's environmental policies were still not finalised.
West Coast-Tasman MP Damien O'Connor as Agriculture Minister assured farmers that any impractical freshwater regulations would be 'tweaked', councillor Brett Cummings said.
"Have we heard anything since the election about whether that's likely to change?"
Smith told councillors it was too early to know who would be in which ministerial position, but even with a more "centrist" government, major changes to the freshwater rules were not expected.
"It's likely to be tweaks rather than anything substantive. So we do have a clear steer on what we need to consider and how we're going to implement it."
The regional council had significant challenges coming its way with work to put the policy into practice, let alone the rules to protect indigenous biodiversity expected next year, Smith said.
Councillor Laura Coll McLaughlin said staff were worried about the resources that would be needed to carry out the wetland mapping required by the new regulations.
"We've already done some mapping but I don't know how we're going to do this in a cost-effective way."
A lot of work was being done by the regional sector on those issues, with councils acting collectively, Smith said.
Cummings suggested the regional council should come up with a list of the "tweaks" needed to make the freshwater regulations workable on the coast.
That was a priority, Mallinson said.
"But I think we must be prudent in the ones we suggest. To make sure we get the best bang for our buck.
"We have to be able to couch it in a way that shows those tweaks won't compromise the outcomes (the government is seeking). We have to make a robust case."
Farmers have said the rules for stand-off areas, measuring pugging depths, percentages and land slope, and an October deadline for resowing pasture are impractical in a region that can get cold spring weather and 4m of rain a year.
They argue that the existing rules and monitoring by the Regional Council have resulted in the best freshwater quality in New Zealand and need little if any change.