Research Programs


Soil Erosion Monitoring Programs

Surface runoff and sediment losses from soil erosion are major contributors to reduction in surface water quality and subsequent degradation of the coral reefs in Guam and the other islands in Western Pacific. The Guam Waterworks Authority (GWA) is presently pumping an average of 2.4 million gallons per day from Ugum River in Southern Guam to the potable water treatment facility. GWA faces an difficult task to keep the plant operating at full capacity when the river is running with high turbidity rates due to heavy rainfall because of permit limitations. This highly turbid water has increased operational costs and along with former poor operation and maintenance practices that led to premature failure of components of the treatment plant system. Most of the Operations Maintenance issue have been resolved but the operating permit still limits GWA’s allowed operating parameters because of unresolved issues with its operating permit. The water that passes the Ugum treatment plant intakes eventually makes its way to the outlet of the river and into the estuary and reef environment. The negative impact of sediment loading tends to result from sporting and hunting activities by people in the Ugum watershed. This in turn has a negative impact on the aquatic environment of Guam in the degradation of coral reef, as well as reduction of fish populations and impediment of the scenery affecting the tourism industry.

WERI researchers have undertaken projects aiming at various methods for estimating upland soil erosion and soil conservation practices. In a project funded by the National Oceanic and Atmospheric Administration (NOAA), WERI researchers developed a GIS based erosion model for the Ugum Watershed. This model, which integrates the Universal Soil Loss Equation (USLE) with the ESRI GIS software package, predicts the soil erosion potential within a watershed and also identifies the areas with highest soil erosion potential. The model is currently used to explore various soil erosion practices with their accompanying costs to determine the optimum erosion control practice that is most effective in reducing soil losses and is most cost effective.

For more information send and email to Dr. Khosrowpanah: khosrow(weri) Erosion Monitoring Programs -