|
Papers
Fate and Transportation of Soluble Reactive Phosphorus in the North Bosque River of Central Texas, Phosphorus (P) forms at sampling sites along the North Bosque River in central Texas were evaluated to determine the fate of soluble reactive phosphorus (SRP) at different points along the river during base and storm flow. Base flow samples were evaluated at eight sites and storm event samples at five sites for data collected between February 4, 1997 and July 31, 1998.
Linking Chemical and Biological Monitoring Components in the TMDL Process,
A TMDL for nutrients was initiated for the North Bosque River in central Texas in 1998. Monitoring associated with the TMDL effort has focused on nutrients due to their role in promoting excessive algae growth as indicated by elevated chlorophyll-a levels throughout the river. Because Texas has only narrative nutrient criteria, linkages between in-stream chlorophyll-a; and nutrient concentrations were needed to develop quantifiable in-stream nutrient targets that would link these biological and chemical components. Proceedings: NWQMC National Monitoring Conference 2000, Monitoring for the Millennium, April 25-27, 2000 Austin TX, pp. 425-434
Future Growth Projections for the Lake Waco-Bosque River Watershed, The Texas Institute for Applied Environmental Research (TIAER) completed future growth projections for the USDA Lake Waco-Bosque River Initiative. A twenty year planning horizon was selected as appropriate for future growth estimates of potential pollution sources in this central Texas watershed.
The TMDL Program: Land Use and other Implications, The total maximum daily load (TMDL) program represents a significant shift in the manner in which water quality objects are achieved. The TMDL process is a holistic watershed approach. TMDLs identify both point and nonpoint sources that contribute to a water body's impairment and seek reductions to assure that pollutant levels entering the water body stay below the target level. Because nonpoint source pollution can be primarily attributed to the manner in which land is used and managed, TMDLs raise the specter of at least limited federal involvement in private land use, and the strong possibility of more assertive state and local involvement.
Demonstration of Phosphorus Best Management Practices in the North Bosque River Basin, The effectiveness of selected phosphorus (P) best management practices in reducing phosphorus concentrations and loadings in runoff from fields high in soil P was evaluated using field plot demonstrations and computer modeling. Eight field plot demonstration sites about 0.4 ha (1 ac) in size were established on dairy waste application fields within the Goose Branch microwatershed of the North Bosque River. A paired watershed approach was used to evaluate improvements in edge-of-field runoff for five P management practices using control plots for pre- and post-BMP comparisons. APEX simulations comparing nutrient management of manure based primarily on P rather than N indicated decreases in average annual soluble and total P loads over a 30-year period of 40 to 60 percent depending on soil type and crop simulated.
Livestock and the Environment: A National Pilot Project Computer Models and Agricultural Policy Development: Applying CEEOT in TMDLs, One key tool available to assess agricultural runoff and its effects is a computer model of point and nonpoint source pollution and management practices and technologies to reduce polluted runoff. Modeling can be useful to describe the status quo and to project the impact of proposed modification to public policy. A suite of models called the Comprehensive Economic and Environmental Optimization Tool (CEEOT) is designed to simulate both environmental and economic effects of policy changes.
Socio-Economic and Biophysical Challenges to Achieving Clean Water Through TMDLs: Two Texas Examples,
Although challenging from both biophysical and socio-economic standpoints, TMDLs have rapidly become a prominent feature of national water quality regulation. This paper discusses some of the challenges and complexities of two Texas TMDLs: The North Bosque River TMDL and the Arroyo Colorado River TMDL. Solutions to meeting water quality goals while accomodating future growth, including effluent trading and new technolgy, are also discussed. Water Resources Impact, Vol. 1, No. 6, November 1999, pp. 12-18
Existing Nutrient Sources and Contributions to the Bosque River Watershed, Over about a two and a half-year period (November 1, 1995 March 30, 1998), flow and nutrients were monitored consistently at 17 sites in the Bosque River watershed, which includes the Middle and South Bosque drainage areas. An empirical model was developed to assess nutrient contribution by source using developed export coefficients for nonpoint sources and information from the eight permitted municipal wastewater treatment plants within the watershed for point source loadings. Sites within the South and Middle watersheds were important in determining nutrient contributions from row-crop agriculture.
|
