The water is generally safe for swimming, officials assure. But, as always, that depends. Inlets to flush out a balmy, stagnant lagoon are few-and-far-between. Bacteria can spike after heavy rains, with no water tests to warn the public, as on the county's ocean beaches.

Safety for swimming in the Indian River Lagoon (Florida) is highly variable and depends on current water quality reports. While many parts are technically open for recreation, the lagoon frequently suffers from harmful algal blooms (HABs) and elevated levels of enteric bacteria (like enterococci) due to stormwater runoff and septic leakage. In 2026, local health departments recommend checking the "Healthy Beaches" or Florida Department of Health website before diving in. Generally, it is best to avoid swimming for at least 48 hours after heavy rainfall, as runoff significantly spikes bacteria levels. You should also stay out of the water if it appears discolored, smells, or if you have open cuts, as the lagoon can harbor Vibrio vulnificus, a naturally occurring but dangerous bacterium.