The flow of silt from the Waihi Dam to nearby tributaries has been called "a horrendous environmental incident" with Hawke's Bay Regional Council members questioning the time taken to stop it.
Silt has been flowing from the dam from an open sluice gate into nearby tributaries after the gates were damaged in a September flood. This then fed into the Waiau River - which in turn flowed into the Wairoa River.
On Tuesday Hawke's Bay Regional Council received an interim and incomplete engineers' report, which had initially been expected on January 18.
Representatives from both parties had met to discuss the report, and would be developing a plan of action following a joint review.
During yesterday's meeting to discuss updates council chairman Fenton Wilson said they needed a bit more urgency from Eastland Group than they had seen so far. He said he had huge sympathy for affected residents, but "was fast running out of patience and sympathy for the Eastland Group".
It was estimated it would another three weeks before the broken sluice gate discharging the silt was able to be closed.
Manager resource use Wayne Wright said: "There's no argument here - this is a horrendous environmental incident."
The first priority was ceasing the discharge from the dam, and then making the dam operable.
Councillor Rick Barker asked if the council was looking at the issue the wrong way round.
"Our interest isn't in the dam, our interest is in stopping the sediment. We seem to be focused on allowing them to get control of the dam ... that's their problem. What we should have said right at the start is the sediment has to be stopped immediately."
Eastland Group chief executive Matt Todd had said the company would work closely with the council to develop a solution but "it won't be a quick fix".
"Right now we're focused on actions which should mitigate any adverse environmental impact. But long-term repair of the dam is complex and the dam's design does not allow for easy remedial work."
He said they were still looking for the solution that was the quickest, and impacted the environment the least. Wairoa contractors had been hired to create a gabion basket structure at the joining of the Waihi and Waiau rivers to stop the silt. Construction was expected to have begun yesterday.
Council resource management group manager Ian Maxwell said: "We don't know how effective it will be, only time will tell."