U.S. Geological Survey Mission Areas

2. Ecosystems Climate and Land-Use Change Water Natural Hazards Core Science Systems Energy and Minerals, and Environmental Health U.S. Geological Survey Mission Areas

4. Investigation of Suspended Sediment Concentrations in Jackson Creek Before and During Construction Activities: Presentation to the Carys Lake Home Owner’s Association January 14, 2014 Celeste Journey, Water-Quality Specialist U.S. Geological Survey South Carolina Water Science Center Columbia, SC

5. Concern • Contacted by Alicia De Myher • Referred by my Water Science Center director, Eric Strom • Requested USGS input • Concern of the Carys Lake Home Owner’s Association is the proposed construction of a new school in Jackson Creek watershed. • Proposed site located immediately upstream of Carys Lake • Proposed site drains to Little Jackson and Jackson Creeks • Past school construction activities resulted in increased sediment deposition in Carys Lake. • Uncertain that appropriate BMPs will be used to prevent a recurrence of the sediment issue in Carys Lake.

6. Proposed Construction Site

7. Requested Input • Evaluation of what would be the best erosion prevention and sediment control Best Management Practices (BMP) • Regulated by South Carolina Department of Health and Environmental Control (SCDHEC) • Options provided in the Storm Water Management BMP Field Manual • https://www.scdhec.gov/environment/ocrm/docs/Field_Manual/OCRM_DHEC_FIELD_MANUAL.pdf. • Outside of U.S. Geological Survey mission • Evaluation of how effective any implemented BMPs were at reducing or preventing sediment erosion • Monitoring of sediment • Within the U.S. Geological Survey mission

8. USGS Mission Areas • Understanding ecosystems and predicting ecosystem change—this science direction is designed to … monitor “biological and physical components . . . of ecosystems.” • A water census for the United States—to, among other things, provide information and forecasts “of likely outcomes for water availability, water quality and aquatic ecosystem health caused by changes in land use and land cover . . .[and] natural and engineered infrastructure.” • The U.S. Geological Survey South Carolina Water Science Center has had a presence in Gills Creek watershed since 1995 • Surface-water monitoring of stream for nutrients, pesticides, suspended sediment, and aquatic biota for over 15 years • Streamflow monitoring • USGS Station 02169570

9. Proposed Construction Site

10. Windsor Lake Proposed Construction Site Carys Lake

11. Potential Approaches • Bathymetric surveys of Carys Lake • Pre-construction • Post-construction • PROs: quantifies impact to Carys Lake • CONs: “damage” is already done • Continuous turbidity monitors • Installed prior to construction to obtain baseline conditions • Provides real-time information to determine if suspended sediment concentrations have increased • PROs: can set up “thresholds” that provide real-time warnings of increases in suspended sediment concentrations • CONs: expensive • Suspended sediment sampling and streamflow measurements in Jackson Creek • PROs: Provide scientifically defensible data to determine if suspended sediment concentrations have increased • CONs: Not as “real-time” as turbidity monitors

12. Potential Approaches • Two possible suspended sediment monitoring approaches • Before and During • ~ 3 ½ years • Data collection 1 year before and 1 year during construction at one site • 1 year of data analysis and report writing • Upstream and Downstream • ~ 2 years • 1 year of data collection at two sites (upstream/downstream) during construction • 1 year of data analysis and report writing • Same cost • Timeline changes

13. Potential Approaches • Two possible suspended sediment monitoring approaches • Before and During • ~ 3 ½ years • Data collection 1 year before and 1 year during construction at one site • 1 year of data analysis and report writing • Upstream and Downstream • ~ 2 years • 1 year of data collection at two sites (upstream/downstream) during construction • 1 year of data analysis and report writing • Same cost • Timeline changes

14. Proposed Construction Site Possible sampling location Windsor Lake Carys Lake

15. Proposed Approach • BEFORE construction activities begin (Baseline Conditions) • Streamflow measured at the time of sampling • 10 samples are collected as depth- and width-integrated samples, not a grab • Samples are analyzed for Total Suspended Solids (aka TSS) and Suspended Sediment Concentrations • 50% of the samples target runoff conditions • DURING construction activities (Impacted Conditions) • Streamflowmeasured at the time of sampling • 10 samples are collected as depth- and width-integrated samples, not a grab • Samples are analyzed for Total Suspended Solids (aka TSS) and Suspended Sediment Concentrations • 50% of the samples target runoff conditions

16. Depth- and Width-Integrated vs. Grab Samples 3 5 10 6 2 4 9 1 7 8

18. Products • End of the year summary and data analysis • Baseline conditions in Jackson Creek • Construction-impacted conditions in Jackson Creek • Statistical comparison of the two conditions • U.S. Geological Survey Open-File Report • Publically accessible on website: http://water.usgs.gov/pubs • Electronic datasets

19. Funding

20. cjourney@usgs.gov 803-750-6141 Questions?