Thermal water quality trading is an emerging policy tool that allows thermal polluters to comply with effluent restrictions by paying nearby landowners to plant shade trees. We created a system dynamics model of a hypothetical thermal trading program and conducted scenario analysis to study how weather, climate, and trading behavior might influence program effectiveness. It is likely that neither thermal trading nor conventional regulation can reduce water temperatures to desired levels, but the model indicates that trading ratios, used to account for uncertainty, lead programs to decrease water temperatures below those produced through conventional regulation.

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Baker, J. P., Hulse, D. W., Gregory, S. V., White, D., Van Sickle, J., Berger, P. A., Dole, D., & Schumaker, N. H. (2004). Alternative futures for the Willamette River Basin, Oregon. Ecological Applications, 14, 313–324.
Caissie, D. (2006). The thermal regime of rivers: A review. Freshwater Biolology, 51, 1389–1406.
Clean Water Services
. (2005). Revised temperature management plan. Hillsboro, OR: Author
Chapin, F. S. III, Matson, P. A., & Mooney, H. A. (2002). Principles of terrestrial ecosystem ecology. New York, NY: Springer
Climate Impacts Group
. (2004). Forest growth and climate change. Seattle: University of Washington
Climate Impacts Group
. (2009a). Climate change streamflow scenario tool. Seattle: University of Washington. Retrieved from http://cses.washing.on.edu/cig/fpt/ccstreamflowtool/sftscenarios.shtml
Climate Impacts Group
. (2009b). About PDO: The Pacific Decadal Oscillation. Seattle: University of Washington. Retrieved from http://cses.washington.edu/cig/pnwc/aboutpdo.shtml
Climate Impacts Group
. (2009c). Climate variability. Seattle: University of Washington. Retrieved from http://cses.washington.edu/cig/pnwc/clvariability.shtml
Cochran, B., & Logue, C. (2011). A watershed approach to improve water quality: Case study of Clean Water Services' Tualatin River Program. JAWRA Journal of the American Water Resources Association, 47, 29–38.
Cochran, R. (2008). [Personal communication]. Hillsboro, OR: Clean Water Services
Conservation Technology Information Center
. (2006). Getting paid for stewardship: An agricultural community water quality trading guide. West Lafayette, IN: Author
Evans, E. C., McGregor, G. R., & Petts, G. E. (1998). River energy budgets with special reference to river bed processes. Hydrological Processes, 12, 575–595.
Faeth, P. (2000). Fertile ground: Nutrient trading's potential to cost-effectively improve water quality. Washington, DC: World Resources Institute
Farrow, R. S., Scheltz, M. T., Celikkol, P., & Van Houtven, G. L. (2005). Pollution trading in water quality limited areas: Use of benefits assessment and cost-effective trading ratios. Land Economics, 81, 191–205.
Ford, A. (2009). Modeling the environment (2nd ed.). Washington, DC: Island Press
Forrester, J. W. (1961). Industrial dynamics. Waltham, MA: Pegasus Communications
Horan, R. D., & Shortle, J. S. (2005). When two wrongs make a right: Second-best point-nonpoint trading ratios. American Journal of Agricultural Economics, 87, 340–352.
Lowry, T. S., Tidwell, V. C., & Cardwell, H. E. (2008, May). Evaluating reservoir operations and other remediation strategies to meet temperature TMDLs in the Willamette Basin, Oregon. World Environmental and Water Resources Congress, Honolulu, HI.
Malik, A. S., Letson, D., & Crutchfield, S. R. (1993). Point/Nonpoint source trading of pollution abatement: Choosing the right trading ratio. American Journal of Agricultural Economics, 75, 959–967.
Meadows, D. H., & Robinson, J. M. (2007). The electronic oracle: Computer models and social decisions. Albany, NY: System Dynamics Society
Morgan, C., & Wolverton, A. (2005). Water quality trading in the United States. Washington, DC: US Environmental Protection Agency, National Center for Environmental Economics
Mote, P., Salathé, E., Duliére, V, & Jump, E. (2008). Scenarios of future climate for the Pacific Northwest. Seattle: Climate Impacts Group, University of Washington
Oregon Department of Environmental Quality
. (2004). Water quality trading: Internal management directive (Version 1.0). Portland, OR: Author
Ribaudo, M. O., Horan, R. D., & Smith, M. E. (1999). Economics of water quality protection from nonpoint sources: Theory and practice. Washington, DC: US Department of Agriculture
Rounds, S. A. (2007). Temperature effects of point sources, riparian shading, and dam operations on the Willamette River, Oregon. US Geological Survey, Reston, VA.
Seedang, S., Fernald, A. G., Adams, R. M., & Landers, D. H. (2008). Economic analysis of water temperature reduction practices in a large river floodplain: An exploratory study of the Willamette River, Oregon. River Research and Applications, 24, 941–959.
Shortle, J. S. (1987). Allocative implications of comparisons between the marginal costs of point and nonpoint source pollution abatement. Northeastern Journal of Agricultural Resource Economics, 16, 17–23.
Shortle, J. S., & Horan, R. D. (2008). The economics of water quality trading. International Review of Environmental Resource Economics. 2, 101–133.
Sinokrot, B. A., & Stefan, H. G. (1993). Stream temperature dynamics: Measurements and modeling. Water Resources Research, 29, 2299–2312.
Summers, R. P. (1982). Trends in riparian vegetation regrowth following timber harvesting in Western Oregon watersheds (Unpublished master's thesis). Oregon State University, Corvallis.
Taff, S. J., & Senjem, N. (1996). Increasing regulators' confidence in point-nonpoint pollutant trading schemes. Water Resources Bulletin, 32, 1187–1193.
US Environmental Protection Agency
. (2003). Water quality trading policy. Washington, DC: Author
US Environmental Protection Agency
. (2004). Water quality trading assessment handbook: Can water quality trading advance your watershed's goals? Washington, DC: Author
US Environmental Protection Agency
. (2007). Water quality trading toolkit for permit writers. Washington, DC: Author
US Environmental Protection Agency
. (2008). EPA water quality trading evaluation: Final report. Washington, DC: Author
Ventana Systems, Inc.
(2005). Vensim DSS (Version 5.5c).
Watanabe, M., Adams, R. M., & Wu, J. (2006). Economics of environmental management in a spatially heterogeneous river basin. American Journal of Agricultural Economics. 88, 617–631.
Woodward, R. T., Kaiser, R. A., & Wicks, A. M. B. (2002). The structure and practice of water quality trading markets. Journal of the American Water Resources Association, 38, 967–979.
Zhang, W., & Wang, K. J. (2002). Modeling for point-nonpoint source effluent trading: Perspective of nonpoint sources regulation in China. Science of the Total Environment, 292, 167–176.