Colorado River Basin - TMDL Data

The Regional Board utilizes a variety of data sources when considering changes to the 303(d) List or when developing TMDLs. Data sources include Toxic Substances Monitoring, monitoring data for regulated/unregulated discharges, and data from other local, state and federal agencies. The Regional Board prefers data that utilizes quality assurance/quality control procedures (QA/QC) that develop reliable water quality sampling results.

One major data source is the Surface Water Ambient Monitoring Program (SWAMP).

SWAMP watershed characterization calls for dividing the Region into watershed rotation areas and conducting synoptic, tributary-based sampling each year in one of the areas. Over a five-year period, all the hydrologic units in the Region are monitored and evaluated. Permanent watershed sites are monitored monthly for conventional water quality parameters, and once during the year for sediment chemistry, bioaccumulation, and benthic invertebrate assemblages. In addition to the synoptic site selection approach, additional monitoring sites are established in each rotation area to provide focused attention on watershed and water bodies known to have water quality impairments. SWAMP utilizes QA/QC procedures to develop reliable water quality sampling results. You may access more information about SWAMP at:

http://www.waterboards.ca.gov/water_issues/programs/swamp/index.shtml

You may also acquire additional information about specific data used for a particular TMDL by contacting the appropriate staff person working on the TMDLs. Please refer to the staff link to determine the staff working on the TMDL you are interested in.