Four major rivers drain into Tampa Bay: the Hillsborough, the Alafia, the Little Manatee and the Manatee. The Hillsborough River lies to the north of the Alafia. The Little Manatee and the Manatee lie to the south.

Although fed by numerous springs, the Alafia is considered a blackwater river. Its waters are filled with tannins, leaf detritus and other organic materials.

Until recently, the Hillsborough River was Tampa Bay’s biggest freshwater contributor. But a prolonged drought, coupled with Tampa’s water needs, has placed heavy demands on the Hillsborough and its watershed, and now the Alafia boasts the largest outflow of any river in the bay.

A small rapid on the Alafia River near Alderman’s ford The Alafia River winds and narrows near Alderman’s Ford; photo by Dave Rau

270,000 Acres

This is the biggest watershed in Hillsborough County. It includes a rich mosaic of natural habitats: hardwood swamps, pine flatwoods, sandhills, oak hammocks, salt barrens and cypress domes. Including the Alafia River, the watershed contains 30 streams, creeks and canals. There are also 11 named lakes and ponds, some of which, like the Medard Reservoir, were constructed by humans.

Lots of Farmland

Much of the Alafia River watershed is rural farmland. The rest is mostly parcels of wilderness mixed with suburban residential developments, urban centers and phosphate mines, or the restored, reclaimed sites of former mines. About two-thirds of the watershed lies within Hillsborough County, while the remainder is in Polk County.

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