PM12 Rio Grande/Transboundary Issues
Exhibit Hall
8:00 AM - Monday, 10 November 2003
(PM180) River Restoration Techniques Explored in the Rio Grande.
Victoria, C1, Hinson, J1, Wooten, R1, Echlin, D2, 1 Parsons, Austin, Texas, USA2 USIBWC, El Paso, Texas, USA
ABSTRACT- An EIS is under preparation for proposed management alternatives of the Rio Grande Canalization Project. The flood control and water delivery project, managed by the United States Section of the International Boundary and Water Commission, covers a 106-mile stream segment from Percha Dam in New Mexico to El Paso, Texas. Current practices include maintenance of over 130 miles of levees, placement of stream training works, and removal and disposal of sediment. Alternatives to existing management practices were proposed to enhance environmental conditions in the project area while meeting requirements for flood protection and water deliveries. Biological surveys were conducted on a seasonal basis to characterize terrestrial and aquatic habitats within the floodway, and to assess the presence of endangered species. Based on the review of aerial photographs, historical data and field surveys, over 50 potential sites were identified for enhancements. Proposed actions ranged from placement of small-scale in-stream structures to extensive modifications such as development of a riparian corridor and seasonal flow changes. Proposed actions were used to develop five alternatives with an increasing level of complexity. Hydrological studies were conducted to assess baseline conditions and alternative river management scenarios. Numerical modeling was performed for the entire stream segment to assess effects of proposed restoration measures on flood control. Use of non-structural approaches for flood control were evaluated in terms of its potential for stream restoration in the Middle Rio Grande. This paper will describe restoration techniques evaluated as part of the EIS, benefits and effects of proposed actions compared to similar projects, and potential for water conservation. Those techniques include planting of native vegetation and control of invasive species (salt cedar), use of seasonal and induced overbank flooding, reopening of former meanders, and changes in land management.
Key words: EIS, Rio Grande, Restoration, Canalization