Sink Branch: Stream Relocation and Reclamation by the Florida Phosphate Industry
Interest in stream reclamation has increased considerably since Mobil Chemical Company (now Mobil Mining and Minerals) established the first experimental stream reclamation research project at Sink Branch. The project began in December 1979 when 0.3 km of Sink Branch, a tributary of the Peace River in Polk County, was diverted from its original unmined channel into a parallel channel excavated on mined land. Excavation was completed in January 1980, but the new channel was not immediately connected with the original in order to establish vegetation to retard erosion. A 1.0 ha tract of reclaimed land north of the new channel was used to test reforestation techniques. The forest experiment area was divided into four treatments: 30 cm layer of topdressed organic soil, 15 cm layer of topdressed soil, fertilization of transplanted trees , and no treatment (control).
Tree-spading began in February 1980 and was completed by March. Potted and bare-root seedlings were planted in the reforestation area in February and March, and again in September to compensate for earlier mortality. On September 15, 1980, the earthen dams at the upper and lower ends of the excavated channel were removed and Sink Branch was diverted into the reclaimed streambed.
Mobil made provisions for monitoring the growth of the forest, but largely ignored the aquatic ecosystem when initial sampling revealed acceptable water quality. This project complements the terrestrial investigation by emphasizing the development of the aquatic invertebrate community, the substrate, and water quality in the stream three years after the diversion was completed. Two locations were selected for study and comparison: the “Mined” channel excavated on reclaimed land, and an “Unmined” section of the stream with an intact riparian forest approximately 1 km upstream from the Mined channel.