Subtask 1.6 Simulate Flow and Salinity of the Pecos for Evaluating River Management Options

This subtask will simulate the flow and salinity of the Pecos River below Red Bluff Dam in order to evaluate river management options.

The first phase of this Subtask involves developing and validating a simple mass balance model useful to assess the effect of inflows from the Pecos River on the salinity of Amistad Reservoir. A simple model that uses data about historical flows and salinity from Foster Ranch, Langtry and Amistad as inputs will be used to analyze short- and long-term impact of the Pecos River on salinity levels in Amistad Reservoir. These analyses include the development of a computer program that can be used to estimate how inflows from the Pecos Basin affect the salinity in Amistad Reservoir.

The second phase of this Subtask involves collecting and generating data needed to develop and verify a water and salt transport model. Data are needed about the dimensions of the Pecos River (for example, river cross-sections at various reaches, slopes, the extent and the types of riparian zones, the dimensions of floodways, the salinity and depth of water tables, soil permeability, the distribution of soil types, physical data about catchment areas, and surface or subsurface inflow). In addition, historical records about flow regimes and salinity levels at various reaches of the Pecos will also be gathered. If the historical data are sufficient, the impact of irrigation over time on river salinity will be analyzed. If historical records of this type are insufficient, these data will only be used to calibrate the model.

The third phase of this Subtask involves developing a water and salt transport model for the main flow of the Pecos River below Red Bluff Dam. The model will be used to assess river management options.

Deliverables for this Subtask

  • Analyze the impact of saline water flows from the Pecos River on the salinity concentrations of Amistad Reservoir
  • Develop a model to simulate the flow and salinity of the Pecos River below Red Bluff Dam

Reports

  • TR-298: Water Balance, Salt Loading, and Salinity Control Options of Red Bluff Reservoir, Texas