Oathill Lake is an idyllic, tree-lined oasis hidden amongst middle-class homes in Dartmouth's Manor Park. The short walking trail along its edge is a popular destination for runners and dog-walkers, and the lake acts as a year-round community centre for people who like to swim, skate or fish. (Full disclosure: I'm a resident of Manor Park.)
But Oathill Lake is in trouble.
It has seen two closures in the past 18 months due to high fecal coliform levels. Its once-thriving frog population has virtually disappeared. Its shoreline is degrading. Garbage and dog waste litter its banks.
"We've known for awhile that there have been problems with the lake," says Iain MacLeod, one of the founding members of Citizens for Oathill Lake. "But it didn't make sense just to go to people and complain. We wanted to go in with solutions."
The group, which has over 80 members including 12 biologists who live in the neighbourhood, has come up with a long list of suggestions to help restore Oathill's fragile ecosystem. Presentations have been made to groups like the Inland fisheries, HRM Recreation and the Halifax Wildlife Association, as well as to city councillor Gloria McCluskey and MLA Marilyn More.
Some of the suggestions, like implementing neighbourhood clean-ups and making residents aware of the damage that the over-use of lawn fertilizers and improper disposal of chemicals can cause, are simple to put into action. Others, like adding more garbage cans along the pathway or sanding rather than salting all the streets bordering the lake, require the city to make changes.
One of the most difficult issues to tackle has been the coliform count. No definitive reason was ever discovered for the extremely high count that caused the lake to be closed for several weeks in July and August of 2009, although residents feared that upgrades to the pumping station at the south end of the lake may have been at fault.
Norman Steele, a member of Citizens for Oathill who works as an environmental professional, has been working closely with the Halifax Regional Water Commission to determine the cause of the contamination and to ensure the lake is safe for swimming.
"I'd have to say that Halifax Water has been really responsive to our questions and concerns. They took the investigation very seriously," says Steele. "I'd have to generally agree with their conclusion that the pumping station was most likely not the problem. It seems like there are a number of other possible explanations: perhaps a possible discharge from the storm water system that empties into the lake. That's a possibility that's also being investigated."
The group has made one suggestion that is stirring debate among users of Oathill Lake: They have asked Inland Fisheries to consider a five-year moratorium on stocking the lake with fish. (The lake was stocked with 3,000 rainbow trout last year and 1,500 are scheduled to be introduced in 2010.)
"We're not targeting fishermen in general. We're interested in the ecology of the lake," explains MacLeod. "But there's no doubt that the year-round fishery we have right now has had a negative impact on the vegetation and the shoreline. And while there are lots of reasons why frog populations decline, it seems likely that the introduction of so many non-native fish has taken its toll."
Alan McNeill, manager for Fisheries Extensions, says Inland Fisheries may consider switching back to a seasonal fishery, but a moratorium is not in the cards: "Part of our mandate is to provide opportunities for people to fish in urban areas, and we do that through supplemental stocking. Rather than a moratorium, we prefer to work with citizen groups to address their concerns."
"We just feel that everyone has taken the lake for granted," says MacLeod. "A five-year stocking moratorium would help to restore the balance."