Geographic Information System Support for Total Maximum Daily Load Analysis of the Mattole River Watershed, Humboldt County, California

摘要

The Information Center for the Environment was able to help the North Coast Regional Water Quality Control Board to quickly develop sediment and temperature TMDLs for the Mattole River Watershed in northern coastal California. ICE used GIS methods and readily-available data to expedite the process. While additional field-based verification is necessary to refine the models, this effort eliminated the need for extensive time-consuming field work throughout the project. ICE is currently performing analyses to evaluate the RipTopo model, as well as investigating methods for converting data into input for models such as SNTEMP and SSTEMP. The methods used for developing these TMDLs are repeatable for other areas with similar problems. They can also be used for monitoring the progress of mitigation efforts in the future. Our work demonstrates that technical TMDLs for sediment and temperature can be greatly assisted by the use of Geographic Information Systems, Remote Sensing and data modeling. USEPA timetables for establishing work plans in the TMDL process are unrealistically short and extreme pressure is placed on agencies to perform research and develop a reasonable estimate of waterbody loadings, submit the TMDL to USEPA, and subsequently reduce the loading. Methods like those described here clearly demonstrate the ability to use an integrated and collaborative process, including spatial technologies, to quickly and effectively develop TMDLs.