CCRA-2: Watershed Modeling and Assessment

Prinicipal Investigator:

Conrad Heatwole
Associate Professor, Biological Systems Engineering, Virginia Tech


Basic hydrologic data characterizing watershed response provides important information for quantifying the water resources of a community. Identifying and quantifying community resources are important steps in being able to manage those resources.  Hydrologic data is also critical for the calibration and evaluation of models that can be used to assess the long-term effects of changes in climate and practices on the watershed. Researchers rely on models as tools to evaluate the biophysical conditions and response of a watershed to a variety of activities and stressors.

The goal of this activity is to enhance the impact of SANREM CRSP’s LTRA projects by providing technical support and a comparative framework in watershed modeling and assessment. Two decision-making tools for planning, managing, and evaluating the effects of SA and NRM at field and watershed scales are being used: high-resolution (sub-meter) multispectral satellite imagery, and biophysical models of watershed hydrology and water quality. The intent is to support current LTRA personnel in achieving and enhancing their project objectives while benefiting from and examining cross-cutting issues.

The main objectives of this activity are to:

  • Support natural resource management at a watershed and policy analysis scale by documenting landscape conditions, quantifying natural resources, and defining changes in land cover and land use using geospatial imagery and analysis
  • Assess the effects of land-use practices and climate change on agricultural sustainability and natural resource management at a watershed scale, and
  • Design and implement low-cost community-based watershed monitoring programs.

The project has been initiated with installation of field instrumentation for watershed hydrologic monitoring, and specification and purchase of imagery to support land-use classification at project sites in Bolivia, Ecuador, Zambia, the Philippines, Indonesia, and Vietnam. Between October 2007 and May 2008, researchers visited nine project sites in Bolivia, Ecuador, Philippines, and Zambia, and selected locations for hydrologic monitoring. In consultation with field and watershed coordinators, they installed equipment, trained partners in flow monitoring, and collected data for land-use classification. The basic approach being used for stream flow monitoring is to select locations in the natural stream channel with a stable cross-section. Each team was provided basic equipment for flow measurement, including a flow meter, electrical conductivity testers, balance, and stopwatch.

In each watershed, at least one complete weather station was installed with equipment to monitor rainfall, temperature, relative humidity, solar radiation, wind speed and direction, and barometric pressure. Local observers record daily rainfall using a manual gauge, and some of them also take daily readings of stream staff gauges. Local observers are critical to the completeness and quality of the overall data collection. Their training is accomplished primarily through hands-on experience in the field.