The fact that the water volume in the Río Motagua is significantly decreasing during Guatemala's dry season is of great concern. Excessive deforestation is causing the drying up of the springs that feed the river. In addition, poor soil management practices cause there to be massive erosion with tons of fertile soil carried away by rainwater during the rainy season. For a six-week period in June and July of 1999, Kim Walton did regular sampling of sediment loads of the Río Motagua in order to develop baseline information related to soil erosion in the watershed. Regular water samples were taken from the river at a location near the village of El Cimarrón, Pachalum, El Quiché.

Río Motagua carrying valuable topsoil away from the mountains of central Guatemala during rainy season.

Ms. Walton prepared a report of her research entitled Río Motagua: Baseline Suspended Sediment Study, July 1999. The results of Kim's study show clearly the incredible erosion taking place in the watershed. As stated in the study's summary, in July 1999 on days when there was little or no recent rainfall, the Río Motagua transported in suspension between 3.7 kg/second and 9.6 kg/second of sediment. The sediment quantities soared when there was moderate to high rainfall. It then measured from 460 kg/second to more than 1,312 kg/second. If these figures are converted into tons/hour, the sediment load would measure between 15 tons/hour and 38 tons/hour on days with little or no rain. However, on days with moderate to high rainfall, the sediment load increased to quantities between 1,825 tons/hour and more than 5,206 tons/hour. This means that at this location on the upper portion of the river, the Río Motagua is carrying 124,956 tons of soil every 24 hours on days of heavy rain. As Kim states in her conclusion, "rainfall washes unprotected soil off the farms and into the river in huge, measurable, and alarming amounts". Kim Walton received a grant from EPIC to assist her in this fieldwork in Guatemala. Additional data is available at Sediment Carried by the Río Motagua in July 1999.

The data collected by Kim indicate what is occurring with normal rainfall. The devastating floods that occurred in Honduras when Hurricane Mitch brought extraordinary rainfall is exactly what could happen in this region of Guatemala. Forests have been clear-cut and replaced with hillside farming, where loose volcanic soils are planted with annual crops, like corn, without respect to the contour and without any type of terracing. For these reasons it is urgent that proper methods of soil and water management be employed in farming this vital watershed. EPIC has supported conservation work in the Departments of El Quiche and Baja Verapaz on the north side of the Río Motagua.

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