From the intersection of I-75 and CR 136, travel east on CR 136 approximately 0.5 miles (0.8 km) to the intersection with McClurg Lane. Turn north (left) onto McClurg Lane and travel approximately 1.1 miles (1.8 km) to the intersection with 64th Terrace. Turn west (left) onto 64th Terrace and travel approximately 0.6 miles (1 km). The spring will be located on the north side of the road.
Blue Sink Spring forms an oval-shaped pool measuring 135 ft (41.2 m) northeast to southeast and 87 ft (26.5 m) northeast to southwest. A maximum depth of 60 ft (18.3 m) was measured from the side of the pool, although locals report a depth of 250 ft (76.2 m). The surface of the pool is entirely covered by duckweed. No boil is visible. No run was observed during the September 2002 visit; however, Hornsby and Ceryak (1998) report a 0.23 mile (0.4 km) spring run. On the east side of the pool, the banks rise approximately 40 ft (12.2 m) above the water surface. To the southwest, the land gently slopes 20 ft (6.1) above the water surface. A two-level wooden observation deck is located on the northeast side of the pool. The spring is within a dense forest on SRWMD land.
It's a sinkhole. I mean, I guess I wasn't expecting tannic water coming from the "spring" itself. The area was pristine and very close to the nearby interstate exit. If you're in the area, it's worth the short drive down just to check it off your list, but not much else.