Spatio-Temporal Variability of Hydroclimatology in the Upper Cauca River Basin in Southwestern Colombia: Pre- and Post-Salvajina Dam Perspective

Abstract

The Cauca River rises in the Colombian Andes and is the main tributary of the Magdalena River, which drains to the Caribbean Sea. The La Balsa station monitors the Upper Cauca basin and is located just downstream of La Salvajina hydroelectric facility. At this station, the discharge time series for November–January during 1950–2019 shows a statistically significant downward break, and change of distribution after 1986 has been documented after La Salvajina started operation. We assessed the spatio-temporal variability of hydroclimatology in the upper Cauca River basin during the pre- and post-Salvajina dam periods to better understand this break. Post-Salvajina, low (high) discharge events are linked to negative (positive) precipitation and soil moisture anomalies that are greater in magnitude and extension than those recorded in the pre-Salvajina period in response to the more intense El Niño events (more intense and frequent central La Niña events) after 1986. Therefore, it is necessary to consider possible future rainfall scenarios and non-infrastructure measures (i.e., reforestation, territorial planning, integrated watershed management, etc.) to mitigate floods and droughts impacts. The contribution of this study is to provide evidence for the need for foresight in the design of any structural or non-structural flood measures.

Impactos ambientales asociados a las hidroeléctricas en Colombia

“…Ramírez et al (2010) estudiaron el régimen de caudales del río Cauca, antes y después de la construcción de la hidroeléctrica Salvajina, destacando la labor del embalse en el control de inundaciones en temporada de lluvias e incrementando el caudal del río mediante el aumento del ujo en temporada de sequía. De igual manera, Cerón et al (2021) determinaron la afectación que generó la hidroeléctrica de Salvajina sobre el nivel de precipitaciones aguas abajo del embalse, mediante un análisis de precipitaciones entre los años 1986 y 2019, concluyendo que los eventos de aumento o disminución de precipitaciones se hicieron más pronunciados en la zona después de la construcción del embalse. Finalmente, Zamora et al (2020) analizaron los posibles efectos climatológicos derivados de la construcción de la hidroeléctrica Prado.…”

Genetic insights into Cyphocharax magdalenae (Characiformes: Curimatidae): Microsatellite loci development and population analysis in the Cauca River, Colombia

“…magdalenae is the only species of the genus reported for the Atrato, Sinú, Canalete and Magdalena-Cauca basin [ 10 , 11 ]. The Cauca River, main tributary of the Magdalena-Cauca basin [ 12 , 13 ], has great economic importance due to its influence on most of the prioritized productive chains in Colombia, which include small exploitations, extensive industries, monocultures, energy generation, mineral extraction, agriculture and fishing [ 12 , 14 , 15 ]. This has resulted in fish being one of the most threatened biological resources, with few or unknown local priorities on rivers [ 16 ].…”