In the spring of this year, Lake Watch of Lake Martin (LWLM) volunteer monitors met with Auburn University (AU) researchers to draft a study plan for the Sandy Creek Watershed. This watershed has been of particular concern as a source of pollution loading into Lake Martin. The Sandy Creek Watershed, about 193 square miles, is the largest of the 22 watersheds (eleven-digit hydrologic units) in the Middle Tallapoosa Basin. The Middle Tallapoosa Basin drains an area of 1,547 square miles from Lake Wedowee Dam downstream to Lake Martin Dam (see map below). It was ranked HIGH priority for 1) siltation and a source of lake turbidity, 2) nutrient enrichment, 3) pathogen contamination, and 4) illegal dumping in the Tallapoosa River Basin Management Plan (see www.cleanwaterpartnership.org/resources-downloads). It is also of high priority because, unlike many other streams in the basin, it drains directly into Lake Martin.
LWLM volunteers sampling Chattasofka at Hwy 280 Bridge
The group was aware of funding opportunities from the Middle Tallapoosa River Basin Clean Water Partnership (MTRBCWP), and submitted a proposal for the watershed study. The MTRBCWP funded the project, and field sampling was conducted monthly, June through September.
Eight sites were identified on seven tributaries of Sandy Creek, and one site was chosen directly downstream of the Dadeville waste water treatment plant on Chattasofka Creek. Watershed field work was divided in half with LWLM volunteer monitors sampling sites 1-4 and AU researchers sampling sites 5-8 (see map below, Sandy Creek Watershed is outlined in red). AU personnel trained the volunteers in sampling and field measurement techniques before starting the actual field sampling. During the first field outing, there was no access to the bridge crossing on Andrews Branch, which was in the heart of Chattasofka Hunting Club lands, so the site was swapped for a site on Chattasofka Creek at the Highway 280 Bridge. The water quality information collected at the Highway 280 site, along with data from the site on Chattasofka above the Andrews Branch confluence can provide insights on the water quality of Andrews Branch.
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Parameters measured in the field included water temperature, dissolved oxygen and specific conductance. Water samples were collected for nutrient, sediment and E. coli analyses, which were conducted in the AWW water quality lab at AU.
Water quality results from the study are summarized below (see graphs).
- All sites had adequate dissolved oxygen (above 5 ppm, the minimum level for aquatic life, mandated by the Alabama Department of Environmental Management)
- Chattasofka Creek was high in nutrients (mean total nitrogen concentration > 1 ppm, mean total phosphorus concentration ~ 1 ppm)
- North Fork of Sandy Creek (downstream from Camp Hill) was highest in E. coli contamination (1 occurrence > 600/100mL, 2 occurrences > 200/100mL)
- Of the three sites on Chattasofka Creek, the site below the Dadeville WWTP was the LOWEST in E. coli
- Norrell Branch was very low in alkalinity and hardness (less than 10 ppm, on average), and generally more susceptible to pollution, particularly acidic runoff (typical from mining activities)
- All sites had relatively low sediment loads since none of the four sample dates captured a rainfall runoff event. During such an event, total suspended solids (TSS, a parameter that correlates well with stream suspended sediment loads) and nutrient concentrations would most likely be a lot higher.
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Click here for larger graphs |
AU project personnel would like to thank the MTRBCWP for making this project possible through their grant program, and also thank the LWLM volunteer monitors who donated their time and talent in drafting and conducting the study. Ultimately, the concerns, awareness and involvement of local AWW volunteer water monitors was translated into a collaborative effort to gather valuable water resource information in the Sandy Creek Watershed. This information can be used to improve resource management practices and water quality for Sandy, and on downstream, for Lake Martin.