A prominent environmental group is decrying Mayor Matt Brown’s promised plan to fix London’s long-busted Springbank Dam, just as a neighbouring First Nation also stands up against it.

The World Wildlife Fund’s Canadian arm unexpectedly weighed in Wednesday, contacting The Free Press to urge city hall to nix any plans to repair the dam — saying it would harm the quality of the Thames River’s water.

“We strongly believe they should consider leaving the dam open and (consider its) eventual removal for the health of the river and the community at large,” said Elizabeth Hendriks, WWF Canada’s vice-president of freshwater conservation.

“A healthy river contributes to a healthy community.”

In a related development, officials with the Chippewas of the Thames First Nation have sent a letter to Brown — a copy of which was obtained by The Free Press — expressing concerns over plans to rehabilitate the dam, built for recreational use but through which the river has flowed freely for nearly a decade.

Though the letter doesn’t explicitly state the downriver band’s opposition, it notes that the last time a dam study was conducted, in 2003, their community was not consulted.

In a speech at King's University College at Western University Wednesday, Chief Leslee White-Eye left no doubt about her opposition to the proposed dam repair.

“Our position is we want that decommissioned,” she said of the structure.

“We’re working really hard with the city on that front.”

The state of Springbank Dam has for years been a sore spot for city hall.

The old structure was decommissioned in 2006 to make way for a newly designed dam worth $6 million. But a test on one of its four gates in 2008 sheared off the bolts, making it inoperable.

A flurry of lawsuits and counter-­suits were filed, but the issues were settled out of court last fall, with the city accepting $3.77 million from the lawyers representing various defendants.

There was no admission of ­liability.

It’s not yet clear what it would now cost taxpayers to complete the repairs.

While running for mayor in 2014, Brown promised to fix the dam. But he stopped short Wednesday of explicitly repeating the pledge, instead citing a new staff report that calls for an environmental assessment to outline all options.

“In light of the staff recommendation, I can see the value in moving forward with an environmental assessment,” Brown said. “It will . . . allow us to find a solution that works for our river and for our community.”

City staff is expected to make public further details — such as the state of the structure, for example — in early February.

But opposition appears to be mounting against a fix, both in London and beyond.

Hendriks, of WWF Canada, says an operating dam would increase “phosphorus loading,” which she cited as a cause of the river’s “poor health.”

A major pollutant, phosphorus can build up in rivers from sources including industrial and municipal wastewater and farm run-off. It contributes to algae growth and reduced oxygen levels in the water.

In London, the operating dam held back a stretch of the river that recreational paddlers once used, but which many Thames advocates say should not be restrained.

In her letter to the mayor, Chief White-Eye notes her community “has the responsibility of protecting the natural environment which is steeped in tradition and ceremonial practices since time immemorial.”

Her First Nation made headlines recently when it became the last opponent left standing against federal go-ahead given for changes to the aging Line 9 pipeline through Southwestern Ontario, including allowing owner Enbridge to ship Alberta oilsands bitumen through the line to refineries in Quebec.

The band is seeking leave to appeal that decision to the Supreme Court of Canada.

With files by Craig Glover, The London Free Press

--- --- ---

SPRINGBANK DAM CHRONOLOGY

1878: Dam and waterworks built at Springbank Park to solve city’s ­sanitation problems. Rowing soon becomes hugely popular, including for spectators.

1930: Springbank Dam built as recreational structure, with removable logs used to control river flow.

1968: Major renovations to dam owned by city and operated by Upper Thames River Conservation Authority.

2000: Flood damages dam.

2003-06: Work on new dam delayed and cost jumps more than 50 per cent to more than $6 million.

2006: Dam shut down in open position, allowing water to flow freely and virtually draining river basin used by paddlers, rowers. A $6.8-million repair begins.

2008: In June, bolts shear off one of four new steel gates after its hinge is forced up by debris during testing.

2009: City launches $5.5-million lawsuit against designers, engineers, saying city paid for inoperable dam. Counter-claims blame city and conservation authority, saying workers tested gates without expertise and if any design mistakes were made, it was the fault of city staff who set parameters for dam design, maintenance and operation.

2014: Matt Brown, in his mayoral run, promises to fix dam.

Sept. 2015: Case resolved in mediation and approved by council, staving off a long trial in 2016.

Dec. 2015: Settlement cheque for $3.77 million arrives at city hall in exchange for confidentiality agreement and no admission of liability by those sued by the city.