Water resource planning is critical for the determination of aspects that may affect a region’s future water supply and is an important component for the development of communities and human activities. It has become an even more critical issue in recent decades, due to increasing pressure on water basins, uncertainties generated by climate change, and rapid variation in socio-economic conditions. More attention must be devoted to understanding water resources and management of the transition to more adaptive water management approaches.

In the Colombian coffee-growing region, water balance and climate change assessments have been carried out in the past five years, especially in the Chinchiná and Otún River basins (Claure Pereira, Portocarrero Lau, & Valencia Quintero, 2015; Purkey & Escobar, 2015). These studies have sought to characterize the conditions of these basins and the impact of climate change there and to develop tools to support decision makers. These studies have helped characterize the high variability of climatic conditions in this Andean region, as well as the impacts of this variability on local supply–demand conditions. They have also served as an example of the kinds of analyses necessary to tackle complex regional water management challenges.

Chinchiná River Basin, contiguos to Campoalegre River Basin. Foto: Natalia Ortiz/SEI

The Campoalegre River basin is contiguous with the Chinchiná and Otún watersheds and has similar climatic and water-demand challenges. The variety of uses of water and the way some of the Campoalegre’s water is diverted to different watersheds adds complexity to water management in this area. In the basin, for example, the return flows from significant hydropower water use are discharged into neighbouring basins, and so act as water transfers. These transfers, along with human, agricultural, livestock, industrial, aquaculture and recreational water use, have drastically and permanently reduced the supply of water downstream. Some water transfers go to the two adjacent river basins, the Chinchiná to the north and the Otún to the south. These two basins belong to separate hydrographical planning units, managed by separate water management authorities. This governance system, in which water transfers may not be accounted for within planning units, exacerbates the challenges of implementing water management strategies and policies.

The goal of the study is to develop a water balance for the Campoalegre basin, to quantify the supply of and demand for water, understand the effects of these interconnected water-governance challenges, and evaluate the vulnerability of water-demand coverage.

This study is innovative because the analysis of results serves local needs and was developed to be a decision-making tool for regional environmental authorities, which, until now, had no such resource. The article will be of interest to policy makers and water resource managers, as it helps identify current and potential future conflicts over water use and the possible need for rationing to reduce water stress.