Academics, councillors and the Restore group met last week for a briefing on the condition of Hamilton's Lake Rotoroa, ahead of a working group being established at Hamilton City Council to improve water conditions.
Restore wants to see the lake swimmable and fishable.
The working group will likely include councillors Garry Mallett, Philip Yeung, Martin Gallagher and Karina Green, all of whom were in attendance except for Ms Green.
Deputy mayor Gordon Chesterman also attended the meeting.
Restore group member David Menkes said he thought making the lake swimmable and fishable was achievable, but making it fully drinkable may be unrealistic.
"We think it's potentially as big an asset as the Hamilton Gardens," he said.
The swimability of the lake is largely dictated by the coliforms in the water resulting from duck faeces.
Putting up signs to educate visitors about feeding the ducks were discussed, but deputy mayor Gordon Chesterman said it would be better to consult interest groups and the public before any signage went up.
Presenting at the briefing, Waikato University student Carl Hartley outlined three possible methods of cleaning lake water, which included reticulation systems to actively treat the water, artificial wetlands which would treat water through natural filtration and lake bed dredging to remove heavy metals and contaminates.
Each had their own advantages and disadvantages.
Mr Hartley said a reticulation system would require a treatment plant or equivalent nearby.
An artificial wetland would require either a huge land area or for water to run through extremely slowly, with the added difficultly of the lake being fed by roughly 50 pipes from a number of locations.This method had been used in some urban areas in Auckland.
Mr Hartley said lake bed dredging would be a temporary solution and very invasive, and although it might remove a number of the heavy metals it would permanently change the depth of the lake.
Waikato University professor of biological sciences Brendan Hicks presented figures collected since 1992 which he said showed that lake clarity had been steadily increasing and a reduction in the amount algae in the water - both positive signs, however Streamlined Environmental water resources scientist Dr Tim Cox questioned these finding, saying they may have been skewed by changes in sampling schedules over the year.
"There' are some issues in the data in terms of less frequent measures more recently. When we're comparing to the older data set that poses some problems to say the water quality is increasing."
He said the bacteria and heavy metals still needed to considered.
"We haven't received any data from city staff and it's not clear to us what data exists," said Dr Cox.
He said before any decisions were made there needed to be a clearer picture of what pollutants were coming in from external stormwater drains compared with what exists and is produced from the lake and lake sediments itself.
Professor Hicks was also able to show encouraging results relating to the aesthetic clarity of the water, with results bordering on mesotrophic levels, which is generally accepted as clear.
The first working group meeting is anticipated to be in February 2016.