People are flocking to Florida. Will there be enough water for them?

While wading through wetlands in the headwaters of the Everglades, where tall, serrated grasses shelter alligators and water moccasins, agroecologist Elizabeth Boughton described one of Florida’s biggest environmental problems: There’s either too much water, or too little. 

An intensifying climate, overexploitation of groundwater, and a development boom have catalyzed a looming water supply shortage — something that once seemed impossible for the rainy peninsula.

“It’s becoming...