Jacksonville's St. Johns River is generally safe for boating and fishing but "there are reasons to be concerned about the health of the river," a newly released annual assessment says.
The ambivalent assessment of the 2024 State of the River Report on the lower St. Johns basin continues a 17-year pattern of finding both bad news and good about the waterway central to Northeast Florida's identity.
The 445-page report compiles data collected by government agencies and academics alike on subjects ranging from water quality to pollution and wildlife in sections of the lower basin, which stretches roughly from southern Putnam County north to the river's mouth at the Atlantic Ocean.
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An upshot of that effort is data suggesting the river's core, called the mainstem, is significantly healthier than the creeks and smaller rivers that reach through neighborhoods across the region.
"The mainstem is suitable for boating and recreation and fishing but not so much the tributaries. This is where most of our problems are," Gerry Pinto, a Jacksonville University research scientist who is one of two principal investigators for the report, said during a panel talk for the WJCT News series Adapt before the report's Monday evening release.
Eight yardsticks for river health in the mainstem, from levels of dissolved oxygen and metals to fecal bacteria and algae-feeding nitrogen and phosphorus, were all considered satisfactory, while three out of five tributary metrics -- fecal bacteria, dissolved oxygen and phosphorus -- were labeled unsatisfactory.
In the basin overall, the report underwritten by Jacksonville's Environmental Protection Board rated 18 metrics satisfactory, 18 unsatisfactory and 10 others were simply uncertain because of incomplete information about factors ranging from bass and flounder populations to the presence of dissolved pharmaceuticals in river water. The report was prepared by scientists at JU, the University of North Florida and Penn State Berks.
The report raised red flags about factors including increased water salinity, decreasing wetlands and struggling undersea grass beds, the submerged aquatic vegetation where many types of fish spend their first months hiding from predators before growing to full size.
But there were bits of good news too.
Despite problems in the river, its sizable blue crab and shrimp populations "are doing fairly well," Pinto said, and the report listed wood stork and bald eagle populations, both dependent on the river, as satisfactory with improving conditions.