State Water Resources Research Institute Program (WRRI)

Details for Project ID 2011AL121G, 2011

Forecasting toxic cyanobacterial blooms throughout the southeastern U.S.

Institute: Alabama
USGS Grant Number: G11AP20212
Start Date: 2011-09-01 End Date: 2014-08-31
Total Federal Funds: $247,891 Total Non-Federal Funds: $262,722

Principal Investigators: Alan Wilson, Kevin Schrader, Russell Wright

Abstract: Water is necessary for our survival. Current environmental challenges (e.g., climate change, point and non-point nutrient pollution, contaminants) have made the general public more conscious of their access to and use of clean, freshwater resources. Such public awareness has driven legislative action that has culminated in complicated tug-of-wars for access to potable water. This is especially true in the southeastern U.S. region whose water resources have been challenged by recent droughts and explosive population growth. Cyanobacteria (blue-green algae) pose one of the most serious threats to freshwater ecosystems given that many cyanobacterial genera produce toxic secondary metabolites, such as the potent liver toxin, microcystin, that can lead to the poisoning of drinking water, fishes, pets, livestock, and in extreme cases, humans. The United States Environmental Protection Agency (USEPA) recently reported through their National Lakes Assessment of 1,028 sites throughout the U.S. that 62% of the sites were classified as eutrophic or hyper-eutrophic, 27% were classified as having moderate to high risk of cyanobacteria, and 30% had detectable levels of microcystin. Cyanobacteria clearly pose a threat to the nation’s water resources, and the coastal plain region (which encompasses much of the southeastern U.S.) had the second highest risk of cyanobacteria (behind the temperate plains region). However, waterbodies throughout much of the Southeast are poorly-studied, except for Florida, regarding the factors mediating toxic cyanobacterial blooms in these systems. This study, in part, will fill this information void. Preliminary monitoring data of 240 waterbodies, including reservoirs, ponds, lakes, and large rivers, collected by the PIs and many collaborators at state environmental agencies in Alabama, Georgia, Florida, Tennessee, and Kentucky show that cyanobacteria are a major environmental issue in the region. For example, using waterbody-averaged data across sampling dates (2008-2010), we found that 87% of the 240 waterbodies sampled had detectable levels of microcystin, 9% exceeded the World Health Organization drinking water threshold for microcystin of 1 g L-1, and one site had a microcystin concentration of 962 g L-1 – almost three orders of magnitude greater than the WHO threshold. Our data also show strong patterns between Secchi depth and nutrient concentrations and chlorophyll a (algal pigment), phycocyanin (cyanobacterial pigment), or microcystin concentrations. Less clear patterns were observed for off-flavor concentrations. Using these abiotic and biotic data, we will test and enhance existing models aimed at forecasting blooms of toxic cyanobacteria and off-flavor events throughout the Southeast. General limnological and biological water quality data testing the utility of these forecasting models will be collected by the PIs in collaboration with federal and state agency scientists from Alabama, Georgia, Florida, Tennessee, and Kentucky during the three year USGS project. Each year, at least 200 sites will be sampled during July and August. We will expand our collaborative network each year to involve additional state and federal scientists. An existing general standard operating procedure will be provided to all participants to standardize data collection and analysis. Samples for microcystin, cylindrospermopsin, saxitoxin, phycocyanin, off-flavors, and phytoplankton identification and enumeration will be returned to the PIs for analyses along with additional water quality data collected by our colleagues. Data will also be exchanged from the PIs to our collaborators. Existing models will be tested with new data, and poorly fitting models will be updated annually as new data become available. Models produced from this project will also be compared with existing water quality models available for sites in the Midwestern U.S. An existing interactive project website incorporating our results will allow users to determine the risk of toxic cyanobacterial blooms in their waterbodies. Our project objectives include (1) enhancing our collaborative network of water quality managers and scientists throughout the southeastern U.S. aimed at monitoring sites for toxic cyanobacterial blooms, (2) testing and improving current models that forecast toxic cyanobacterial blooms and off-flavor events in freshwater lakes, reservoirs, and ponds throughout the southeastern U.S., (3) organizing annual workshops in Alabama and Florida to discuss project findings with our colleagues in addition to training state and federal scientists, water quality managers, and aquaculturists on standard techniques to measure microcystin and phycocyanin concentrations and to enumerate phytoplankton, and (4) training graduate and undergraduate students on field sampling and laboratory-based water quality analytical analyses. Data derived from this research project will directly enhance the southeastern region’s water resources by identifying lakes that are negatively affected by cyanobacterial blooms in addition to highlighting the factors mediating algal bloom development. Water quality managers will use this information to improve their efforts aimed at reducing the negative effects of harmful algal blooms.