QUALITY ASSURANCE NARRATIVE STATEMENT

The items listed below correspond to those of Instructions: Quality Assurance Statement.

  1. The project will perform hydrologic, hydraulic, and sedimentological studies in the Tecate Creek watershed, to support ongoing studies of stream corridor restoration. Watershed characteristics will be obtained from geographic maps prepared by the Binational Watershed Vision Project. Watershed characteristics include areas, hydraulic lengths, soil types, vegetation types, and channel slopes. Channel cross-sections will be measured in the field or established from design considerations. Channel infiltration velocities will be assessed from field sampling of soils. Existing geographic, topographic, soil, and vegetation data is considered adequate.

  2. The project will use geographic data to simulate rainfall-runoff processes in the watershed using established hydrologic methods. The hydraulic modeling will be performed using channel cross sections every 100 m. This reach distance is considered adequate for this type of hydraulic modeling. The bed material samples for the stream mechanics model will be taken every 500 m. This sampling distance is considered adequate for this type of study.

  3. Soil samples will be taken on strategic locations along the stream, with aim to analyze these for size distribution and other soil properties. These samples will be taken to the SDSU Geotechnical Laboratory for grain size analysis and other geotechnical tests.

  4. Analytical methods will be used as part of the GIS modeling, including the ESRI Spatial Analysis. The performance of the model will be tested against local knowledge developed by the Mexican consultants through several years of field and institutional work on Tecate Creek.

  5. This study will used established hydrologic and hydraulic models, such as the U.S. Army Corps of Engineers' HEC-HMS and HEC-RAS. The study will also use the RAINFLO and MODELRIVER models, developed by Dr. Victor M. Ponce at SDSU. The RAINFLO model follows the HEC-1 standard, while the MODELRIVER model follows the HEC-6 standard. The HEC-1 standrad converts event precipitation into floow runoff, while the HEC-6 standard calculates the aggradation or degradation of a streambed, following natural or anthropogenic impacts.

  6. The success of the project will be assessed by reviews by peers, including U.S. and Mexican officials. The project team will work in close cooperation with local stakeholders to ensure that the results are used in the development of the Tecate Creek corridor.