GENERAL
The Sweetwater Branch Watershed encompasses 3.3 square miles of central Gainesville. Sweetwater Branch flows through the Duck Pond area and the heart of downtown Gainesville, then through the Depot Avenue residential/industrial district where it is joined by Rosewood Branch near SE 10 th Avenue. Sweetwater Branch continues southeast through residential and natural areas before reaching an old landfill site. Further downstream, reclaimed water is discharged into the creek from the GRU Main Street Water Reclamation Facility (WRF). The creek continues south of Williston Road (SR 331) and flows into Paynes Prairie State Preserve where it ultimately discharges to the Floridan aquifer via Alachua Sink. Historically, Sweetwater Branch was a small spring-fed stream that meandered through a young Gainesville. As the city grew, so did the need to prevent flooding, hence many segments of the creek were channelized. Today, an estimated 60% of the area in the watershed is impervious as the creek flows through highly developed residential and commercial and areas in the upper and central parts of the basin. Only a small portion of the watershed, the area south of the GRU Main Street WRF and the portion of the creek that flows through Paynes Prairie, remains undeveloped.
DESCRIPTION
Only a few segments of Sweetwater Branch have over 60 feet of natural riparian buffer zone, which is the minimum considered optimal for a waterway. Sadly, most of Sweetwater Branch has buffer zones ranging from zero to 20 feet. A wide riparian buffer of native tree and plant species provides a canopy to shade the stream, allows slow percolation of rainfall to recharge the surficial aquifer system, reduces rapid stormwater runoff that that can cause erosion and sedimentation, provides habitat for wildlife, and retards the impact of man-made activities on the stream system. In the upper reaches of Sweetwater Branch, much of the creek lacks a shaded canopy; however, the natural canopy is prevalent in the lower reaches prior to entering Paynes Prairie. As you walk along the creek you may see several native trees including box elder, water oak, pignut hickory, blue beech, sugarberry, and sweetgum. However, the understory vegetation is poor and is comprised of opportunistic species such as elderberry and numerous invasive exotic species such as Mexican petunia, wild taro, and air potato. Such deviations from natural plant communities can alter soil properties, affect wildlife populations, and change the overall ecology of an area. Aquatic vegetation is uncommon in Sweetwater Branch due primarily to erosion and sedimentation with the exception of some upper channelized portions of the creek where the invasive, exotic hydrilla and native sagittarria species are present.
In spite of these factors, however, Sweetwater Branch does support several forms of wildlife. Fish species such as the mosquitofish are abundant in most reaches of the creek. Common birdlife includes most of the native songbirds of the Gainesville area, woodpeckers, red-tailed hawks, osprey, and barred owls. Alligators, turkeys, and aquatic turtles are quite common as the stream approaches Paynes Prairie State Preserve.
WATER QUALITY
Most of the urban development within the basin occurred prior to state and local requirements for stormwater management (retention/detention basins, etc.). The lack of stormwater management systems allows the direct discharge of non-treated stormwater to Sweetwater Branch. Rainfall no longer slowly infiltrates through the ground, gradually entering the creek through surficial aquifer springs and seeps, but instead flows rapidly into the creek as the rainfall event occurs, intensifying erosion and pollutant transport to the creek. In addition to flowing through a highly urbanized area, the creek bisects an industrial portion of the city and because of this urban and industrial location, a number of point pollution sources exist throughout the watershed.
Point sources of pollution
Since 1914, the GRU Kelly Electrical Generating Station (GRU Kelly) has discharged cooling tower and boiler blowdown (water pumped up from the Floridan aquifer used to cool equipment that has been heated in the process of electricity generation) into Sweetwater Branch. This discharge is permitted by the Florida Department of Environmental Protection (FDEP). A comprehensive assessment of the creek in the vicinity of GRU Kelly showed that no organic pollutants were detected in the discharge. A previous assessment concluded that the receiving waters appeared more affected by stormwater than by the discharge from GRU Kelly.
Downstream from GRU Kelly are the former CSX Transportation property, a former city dump, and the GRU Main Street Water Reclamation Facility (WRF). The CSX site has been an industrial site since 1887. From 1887 to 1913, the site belonged to the FC&P Railroad. Since that time, the site has been utilized by several different businesses including a coffin-manufacturing company, cotton and lumber mills, and an ice supplier.
The CSX property is contaminated with coal tar residuals from the former Manufactured Gas Plant (MCP) located north of the site. The site has been selected as an EPA Regional Brownfields Pilot Project. Plans are currently underway to remediate the property and convert the area into a centralized stormwater treatment facility consisting of created wetlands and wet detention basins. This will be surrounded by a city park consisting of passive recreation facilities.
The old city dump is a former landfill located adjacent to Sweetwater Branch, just upstream of the GRU Main Street WRF. The hazardous waste potential of this site was rated as minimal in a 1987 report by the Alachua County Department of Environmental Services. However, natural and accelerated erosional processes continue to expose the landfill material which now litters the streambed. The City of Gainesville Public Works Department is conducting assessment activities at the site under the direction of FDEP.
The GRU Main Street WRF discharges reclaimed water into Sweetwater Branch upstream of Williston Road. The plant opened in 1930 as a primary treatment facility with a treatment efficiency of about 30%. The plant has since undergone three upgrades, the most recent being in 1992. It is now an advanced treatment facility with an efficiency of 99% and an average throughput of approximately 6.0 million gallons per day (MGD). Wastewater treatment includes preliminary treatment, three aeration basins, three secondary clarifiers, continuous backwash filters, pH control, chlorination, dechlorination, and post-aeration. Treatment residuals are stabilized and land applied at permitted sites. As a result of the increase in treatment efficiency over the years, many of the problems historically associated with the discharge of the reclaimed water have greatly diminished. However, the elevated concentrations of nutrients, primarily nitrogen and phosphorus, remain a concern. Additionally, the streamflows downstream of the WRF have caused serious erosional problems. The streambed is eroding vertically, the banks are steep and scoured, and heavy sand deposition smothers habitat. The increased nutrients in Sweetwater Branch enter Paynes Prairie further downstream, where they have the potential to alter the ecological characteristics of the wetland prairie. While some of the nutrients are sequestered in the wetland prairie system, the remaining nutrients enter the groundwater in the Floridan aquifer via Alachua Sink.
MACROINVERTEBRATES
The health of streams can also be evaluated by determining the number of pollution-sensitive benthic macroinvertebrate organisms present. These organisms, such as the larvae of dragonflies and damselflies are susceptible to degradation of water, sediment, or habitat quality and their populations respond to these cumulative factors over time. Macroinvertebrates are also important food sources for adult insects, fish, frogs and birds. It is estimated that 80% of Sweetwater Branch lacks the in-stream habitat to support a healthy and diverse macroinvertebrate community. Sand smothering, lack of natural riparian buffer zones, bank instability, and increased water velocity all contribute to the impairment of habitats found in the creek.

Sweetwater Branch Creek , Gainesville, Florida

WHERE TO VISIT THIS CREEK
A good place visit the creek is at Sweetwater Branch Park, located directly east of the county public library and federal building. The park is the site of a riparian zone revegetation project being conducted by a local creek cleanup and restoration group, Adopt-a-River.