This article presents a low-cost approach to reconstructing river discharge in the Tomarrazón-Camarones Basin in La Guajira, Colombia, where flooding is frequent and instream sediment mining is intense but no official gauges exist.

It combines satellite rainfall data with ground observations to feed a HEC-HMS hydrological model, calibrated using water level sensors and field measurements. The model reproduced observed flows well (R² = 0.981 for hydrographs, 0.87 for peak flows) and was used to build 1973–2024 duration curves and return periods for peak discharges, supporting flood management and sediment budgets.