Those behind the initiative said the ORC has plenty of money to tackle the problem.
The ORC had $56million in cash reserves, no debt, and a Port of Otago asset worth more than $400million, Guardians of Lake Dunstan chairman Andrew Burton said.
The ORC has confirmed the figures, but says most of the cash reserves are dedicated to specific activity.
Of the $56million in cash reserves, $15.3million was unallocated and in general reserves.
These were generally used for one-off costs, not programmes requiring ongoing work, ORC director corporate services Nick Donnelly said.
But Mr Burton and Dunstan Otago regional councillor Michael Laws have said it is ‘‘ridiculous’’ the ORC has so much money yet still says it cannot allocate funding to help tackle lagarosiphon in Lake Dunstan.
"They have $56million in reserves and no debt," Mr Burton said.
"They should use some of that money to tackle this [lagarosiphon] head on.
"It’s our money, it’s not their money. It’s ratepayer money."
The petition asks the ORC to "take prime responsibility for controlling and then eradicating the invasive pest weed lagarosiphon from Lake Dunstan and associated waterways, including the direct funding and resourcing of pilot programmes aimed at combating this pest".
It arose from a special meeting of the Guardians of Lake Dunstan earlier this month, when Mr Laws told Cromwell residents they needed to "get agitated" and "start making some noise" to demand the ORC take more action.
At present, Land and Information New Zealand (Linz) is officially the lead agency for lagarosiphon.
It contributed $50,000 a year towards the issue for Lake Dunstan alongside another $50,000 annually from Contact Energy.
The ORC has nothing in its 2017-18 draft annual plan for managing lagarosiphon in Lake Dunstan, but has previously said it contributes about $30,000-$40,000 of staff time annually to inter-agency work.
Mr Burton said it was estimated there was now about 500ha of lagarosiphon clogging up Lake Dunstan, but authorities were dealing with only about 70ha in "high value areas", mainly boat ramps and camping spots.
Mr Laws said the ORC should be the lead agency for dealing with lagarosiphon as it had a statutory responsibility to protect the environment.
But "every agency says it’s not their problem — Linz, Contact, Fish and Game and the ORC. There’s a race to the exit to get away from responsibility".
Mr Burton encouraged Cromwell residents to make submissions on the ORC’s 2017-18 draft annual plan, asking the ORC to take more responsibility for tackling lagarosiphon and allocate more money to the issue.
The petition would be circulated in the Cromwell region for the next month and probably presented to the ORC at its June meeting, he said.
Key facts
What the Otago Regional Council is worth:
• Cash reserves of $56million
• No debt
• Equity in Port of Otago worth $402million, including $273million of investment property.
What the Otago Regional Council has budgeted for lagarosiphon next financial year:
• About $50,000 for Lake Wanaka
• $30,000 for Lake Wakatipu and the upper Kawarau River
• Nothing for Lake Dunstan, although the ORC has previously said it contributes about $30,000-$40,000 of staff time annually to inter-agency work.
