Submitted to: Congress of International Association for Hydraulic Research Proceedings
Publication Type: Proceedings
Publication Acceptance Date: August 1, 1999
Publication Date: N/A
Interpretive Summary: The quality of many of our nation's surface waters is degraded. Nutrients and sediments are the principle sources of impairment. The sources of pollution vary, but agriculture is the major contributor for rivers and lakes. Further, channelization of streams has led to unwanted erosion and deposition of sediments. The USDA-Agricultural Research Service in partnership with other agencies and universities has developed computer simulation models to address watershed water quality (AnnAGNPS), stream channel stability/evolution (CONCEPTS), and riparian ecology (REMM). This paper presents an overview of these models and discusses how integration of these models offers an ideal tool for watershed planners and managers. The integrated technology is able to predict the fate of agricultural contaminants and sediments from fields through riparian buffers into and along stream systems.
Technical Abstract: Many of the 5.5 million kilometers of rivers and streams are in a degraded condition. Rivers have been channelized and their floodplain riparian zones overtaken by land development. Sedimentation and excess nutrients are the most significant causes of degradation, many of these loads coming from agricultural lands. The U.S. Department of Agriculture (USDA) has joined other federal organizations to develop solutions and guidelines to restoring damaged channel systems. The physical processes that affect stream corridors occur at a variety of scales. Therefore, stream restoration designs need to be based on integrated watershed assessments of the environmental processes in the watershed, riparian zone, and stream channel. The USDA Agricultural Research Service is developing various numerical models that integrate hydrologic, geomorphic, and biologic processes occurring within the watershed, riparian zone, and stream channel. The AGNPS 98 suite of models simulates the governing processes in the upland areas (AnnAGNPS model), the stream channel (CONCEPTS and SNTEMP models), and the fish habitat (SIDO model). The REMM model simulates the governing processes in the riparian zone. The integration of the above models forms a comprehensive tool that enables engineers, geomorphologists, and biologists to evaluate stream restoration designs.