The Waratah-Wynyard Council and the Waratah community continue to campaign for the Waratah Reservoir Dam to not be decommissioned by TasWater.
Waratah-Wynyard mayor Robby Walsh said TasWater's decision to decommission the dam was disappointing.
"We have fought long and hard to retain it," Cr Walsh said.
"It's very disappointing, as it is very vital to the old mining community and heritage town.
"We think it is a special place for Waratah."
Waratah resident Russell Langfield argued the decommissioning decision was two-fold.
"The first issue is with TasWater wanting to decommission the Waratah Reservoir since 2017 and now having permission to from the DPIPWE Dam Safety Regulator and the second issue, related to the first, concerns the decrepit state of the Waratah Lake Weir located downstream of the TasWater Water and Sewage Treatment Plant, which is built at the very uppermost level of the Waratah Lake.
TasWater was contacted for comment.