Water Resources Research Act Program

Details for Project ID 2011OK207B

Incorporating Ecological Costs and Benefits into Environmental Flow Recommendations for Oklahoma Rivers: Phase 1, Southeastern Oklahoma

Institute: Oklahoma
Year Established: 2011 Start Date: 2011-03-01 End Date: 2013-02-28
Total Federal Funds: $25,000 Total Non-Federal Funds: $50,000

Principal Investigators: Caryn Vaughn, Jason Julian

Abstract: Providing a safe and sustainable water supply while also providing for economic growth and maintaining natural ecosystems is a serious challenge in Oklahoma, especially given its increasingly limited water resources. Accomplishing this will require consideration of both the economic and ecological costs/benefits of different water management strategies. Determining the ecological costs/benefits of in-stream flow regimes requires quantifying real, measurable ecological characteristics of rivers and determining how these change under various flow scenarios. In this proposal, we focus on rivers in southeastern Oklahoma because (1) water from these rivers is in high demand to meet water needs across the state; and (2) these rivers are known for their relatively pristine water, high biological diversity, and multiple endangered species, including several species of freshwater mussels (clams). Freshwater mussels are filter feeders and thus provide important ecosystem services in rivers, particularly water filtration and nutrient recycling. The ability of mussels to provide these services changes with different instream flows because water volume partially governs water temperature, and water temperature determines mussel filtration and nutrient recycling abilities. In addition, when mussel populations are adversely affected, it is likely that other aquatic species are at risk. Their high sensitivity to changes in flow regimes and water temperatures thus make freshwater mussels an early-warning test system for determining the ecological costs/benefits of environmental flow recommendations. We propose to combine information on (1) discharge and water temperature under various in-stream flows in different seasons with (2) information on how mussels perform the ecosystem services of water filtration and nutrient recycling under those conditions to (3) produce an empirical, predictive model of the ecosystem services provided by mussels under various flow and atmospheric conditions. We will model the Kiamichi River because we already have rigorous data on where mussels occur, their identity and abundance, and the physical, hydraulic characteristics of river reaches containing them. In addition, this river is under the most pressure for regional water diversions. We will conduct laboratory experiments to obtain additional data on how filtration and nutrient recycling rates of different mussels species change with temperature. We will place automatic data loggers in 10 river reaches of the Kiamichi (above and below reservoir and tributary inputs) to obtain daily information on discharge and water temperature. We will create a GIS-based model that uses incoming solar radiation, topographic and riparian shading, and flow and hydrographic data. This GIS-based model will be combined with the lab experiment data to produce an empirical model that will allow us to predict the ecosystem services provided by mussels under different in-stream flows and atmospheric conditions. This multi-component model can then be used to evaluate various in-stream flow models, such as the USGS Hydroecological Integrity Assessment Process, to make specific environmental flow recommendations. Once we have derived an empirical model for the Kiamichi River, we will be able to use this approach to produce models for other important rivers in the region (i.e. Little, Mountain Fork, Glover) because these rivers have similar flow regimes, geomorphic features and mussel faunas. Finally, this same approach should apply to other ecoregions in the state once the appropriate ecological indicators and characteristics are identified for those regions.