Lake Dora, Mount Dora: The Postcard Lake That Once Topped the Chain for Toxic Algae

If you walked the Mount Dora lakefront in the fall of 2001 — past the lighthouse at Grantham Point, down to the docks where the tour boats idle — you'd have seen what you always see. A lake that looks like a postcard. Sailboats out toward Tavares. Cypress at the edges. The kind of view that built a downtown full of antique shops and cafés and a tourism economy that keeps the sidewalks busy on Saturdays.

What you wouldn't have seen, unless you read the Orlando Sentinel that October, was the county study that had just landed. Lake Dora, it reported, had the highest concentration of toxic algae of any lake on the Harris Chain. Higher than Lake Griffin. And Griffin, at the time, was considered the most polluted water body in the state of Florida.

That's the part most people who visit Mount Dora don't know. The lake that anchors the most charming small-town waterfront in Lake County was, for a stretch of years, quietly the worst chemistry on a chain already infamous for its chemistry.

The reason has more to do with what flows in than what happens on Dora itself. Lake Dora sits in the middle of the Harris Chain, downstream of Lake Beauclair and the Apopka-Beauclair Canal — which means it inherits whatever Lake Apopka, the great damaged shallow lake to the south, has been pushing north. A 1995 study cited in the state's eventual phosphorus TMDL for Lake Dora estimated that discharges from Lake Beauclair contributed roughly 76 percent of the phosphorus and 86 percent of the nitrogen entering Dora. The lake wasn't generating its own crisis. It was catching someone else's.

What grew in that nutrient soup was the part that made the 2001 headlines alarming rather than just unpleasant. State sampling on Dora documented Cylindrospermopsis and Microcystis — two cyanobacteria genera that don't just discolor water and smell bad, but produce toxins that can sicken people, pets, and wildlife. Cylindrospermopsis in particular had been linked to fish kills and health concerns on Lake Griffin a few years earlier. Finding more of it in Dora than in Griffin was the kind of result that made water managers sit up.

To say the state's response was the slow, unglamorous kind. In August 2002, the Florida Department of Environmental Protection adopted a Total Maximum Daily Load order for Lake Dora and the Dora Canal — a regulatory ceiling on how much phosphorus could legally enter the lake, with reductions assigned upstream. The St. Johns River Water Management District, which controls levels on Dora through the Burrell Lock and Dam down on Haines Creek, layered that into the broader Upper Ocklawaha basin work that's been grinding away at Apopka for decades. None of it was the kind of thing that made postcards. All of it mattered.

What's notable, walking the Mount Dora waterfront a generation later, is how little of that story is visible. The antique boat festivals still come every spring. Tavares across the lake still calls itself America's Seaplane City and still launches yellow-hulled aircraft off the water on weekends. Major League Fishing brings tournament boats to the chain. The dinner cruise out of Mount Dora still runs the Dora Canal — that cathedral of cypress between Dora and Eustis that people have been calling one of the most beautiful waterways in the world for a hundred years. None of it announces that the lake spent the early 2000s carrying a title nobody wanted.

The water is better than it was. Not pristine — Dora is still a working lake at the middle of a chain that drains a developed, agricultural, century-altered landscape, and the algae have not gone away on any Florida lake that ever had them. But the worst-of-the-chain headline belongs to 2001, and the regulatory architecture that followed has been pulling the numbers in the right direction ever since.

It's worth knowing, the next time you're standing at Grantham Point watching a seaplane lift off the far shore. The view that built Mount Dora is doing better now than it was when the tour boats were already running and nobody was telling visitors what the county study had found. The lake had a bad chapter. It also had people working on it. Both things are part of what you're looking at.