At Thursday's Otago Peninsula Community Board meeting, chairwoman Irene Scurr said the board was concerned funding to replenish sand at small beaches at Broad Bay and Macandrew Bay was not available.
The board first asked the Dunedin City Council to investigate options for replacing sand at the beaches about four years ago.
Dunedin City Council Parks and Reserves team leader Martin Thompson told the board funding to replace sand at the artificial beaches was not available in council's 2008-09 annual plan.
"About four years ago we asked council to consider keeping a watch on the sand levels and they applied for and received long-term consents.
"We did get a verbal undertaking funding was available as part of the council's dune management plans. But instead, funding went to the rescue package for Middle beach," Ms Scurr said.
While board members recognised decreasing sand levels at the beaches was "not coastal erosion on a serious scale," they were concerned sea water could damage walls and structures at the edge of the two beaches over summer and limit recreational use, she said.
Board member Christine Garey said less sand at Broad Bay meant walls and steps could be undermined by seawater.
Elderly people and children using the beach had to "jump the gap", she said.
"People in the community have talked about it over time.
I was astonished yesterday because there have been and will be ongoing problems if sand isn't replaced.
The beaches are used a great deal by families and after school because there's no other beaches as sheltered for smaller children and preschoolers."
Board member John Bellamy said tidal current could cause sand to build up against a retaining wall at the Macandrew Bay beach, and it subsequently blew over a garden and sections of road.
Levelling and replacing sand would extend the beach area back to the waters edge, he said.
