The high temperatures, limited rainfall, and forest fires that have struck the Valle de Aburrá region are starting to reflect in the declining flow rates of rivers and streams. Daniel Ruiz, the coordinator of Siata, reports that most of the streams in the Valle de Aburrá have experienced a 7% drop in their flow rates, and some community reports suggest drops of up to 10%. The primary causes are high temperatures over the past two months, reduced rainfall, and the forest fires.
Out of the 151 vegetation cover fires that the Valle de Aburrá has experienced this year, 95% were intentional, according to the Metropolitan Area. These fires have disrupted the water regulation process in the supplying basins. Vegetative cover is crucial for basins to recharge and retain water. The region has lost vegetative coverage equivalent to 120 football fields recently, severely disrupting this process.
While many in the metropolitan area don’t associate the reduced flow rates with water scarcity, Juan Camilo Murillo, a researcher in Hydrology and Environmental Management, emphasizes the underestimated importance of internal basins for water supply. While more than 90% of the water supplying the EPM system comes from external basins, when considering all supply systems in Valle de Aburrá, the region’s dependency on its own basins is about 30%. Even 8% of the water treated by EPM plants comes from streams originating in the metropolitan area.
With over 20 major streams influencing Aburrá’s water supply and all of them experiencing reduced flows, authorities urge the public to understand the urgency of reducing water consumption. During the 2016 El Niño, Valle de Aburrá’s streams saw up to a 40% reduction in their flow. With considerable reductions already and El Niño yet to strike, the impending water scarcity could be even more severe.