Andrew Burton [left] and John Wilson told the Otago Regional Council at its meeting in Cromwell on Wednesday while they were happy enough with the work being done over about 70ha of the lake, authorities needed to spread their control measures to the full 500ha the weed has colonised.
Mr Wilson said Lake Dunstan was becoming the ``septic tank'' of the lakes further upstream and Cromwell's future as a tourist town was under threat as a result.
Immediate past chairman of the Lake Dunstan Guardians group Mr Burton said lagarosiphon control and monitoring in Lakes Wanaka and Wakatipu received at least $400,000 of funding each year for each lake, while Lake Dunstan made do with $175,000.
The guardians and the council met formally on the lake shore yesterday, the guardians urged to make their concerns known through the Lake Dunstan Aquatic Weed Management Group, which represents nine interest groups.
