click to enlarge CAMILLE RESPESS

It started with a social media inquiry — two dead fish had been found in Boathouse Lake in south city's, and a neighbor was curious.From there, the city got curious, and on Monday, it called the state's Department of Natural Resources. Staffers took water samples Tuesday. And when they confirmed it was blue-green algae, the city closed the lake.The problem wasn't just the presence of algae, says Greg Hayes, director of parks, recreation and forestry for the city of St. Louis. It was the type: the U.S. Environmental Protection Agency links blue-green algae to potentially dangerous toxins that can kill people or animals and create water dead zones. Hence the signs now up at the lake: Fishing is currently strongly discouraged.Still, despite the potential scariness of those words, Hayes is hopeful this will be a short-term problem. "We hope to have the lake reopened by the weekend."It couldn't be soon enough for some neighbors. Sarah Wood Martin, the alderwoman for the neighboring 11th Ward (which does not include the park itself) says the closure comes with the territory of having a water resource, but is still a bummer. “I hate that it’s not openable right now,” Martin says.Since the problem seemed to be concentrated on the north end of the lake, city crews have been using water cannons to increase the water volume, and relying on its fountain system to increase circulation. Hayes says state officials told them they'd acted just fine — and "they'd be surprised if many lakes wouldn't show this in the hot summer months."In addition to scorching summer weather, Hayes notes, Carondelet has a potential aggravating factor: a plethora of geese. Neighbors are known to feed them, which encourages them to stick around, and which ultimately results in them using the lake like a giant latrine.And so while the parks department generally tries to "stay out of the sign business," as Hayes says, you may see new signs going up even as the temporary closure signs soon come down — these instructing you not to feed the geese."Geese," says Hayes, "are a problem."See a potential problem at any city park? Hayes encourages you to make a call to the citizen's service bureau via 314-622-4800.