This paper focuses on calibration and validation of a hydrologic model of the Rio Conchos Basin, a main Mexican tributary of the binational Rio Grande Basin. The Rio Conchos provides approximately 55% of the water deliveries to the United States under the 1944 water treaty signed between both countries. The hydrologic modeling has been developed using the one-dimensional, two-layer soil moisture accounting scheme embedded in the Water Evaluation and Planning (WEAP) model. A 10-year period was used to calibrate the model, which was achieved by a trial-and-error method for the adjustment of the model parameters. The results show a Nash-Sutcliffe coefficient of 0.84 at Ojinaga station (mouth of the basin) and 0.81 at La Boquilla, indicating good model performance. In general the model predicts well the monthly, annual, and maximum flows; but there are significant differences between the model values and undeveloped (naturalized) flows for low flow periods, especially at La Boquilla station. For model...

Global projections of climate change indicate negative impacts on hydrological systems, with significant changes in precipitation and temperature in many parts of the world. As a result, floods and droughts are expected. This article discusses the potential effects of climate change and variability on the maximum precipitation, temperature, and hydrological regime in Devil’s Creek, Tacna, Peru. The outputs of precipitation and daily temperature of fifteen regional climate models were used for the RCP4.5 and RCP8.5 emission scenarios. The methodology used includes the bias correction and downscaling of meteorological variables using the quintiles mapping technique, hydrological modeling, the evaluation of two emission scenarios, and its effect on the maximum flows of the stream. The results of the multi-model ensemble show that the maximum annual precipitation will probably increase by more than 30% for the RCP4.5 and RCP8.5 scenarios for the 2021–2050 period relative to the 1981–2005 period. Likewise, as expected, the maximum flows could increase by 220% and 154% for the RCP4.5 scenarios for the 2021–2050 and 2051–2080 terms, respectively, and 234% and 484% for the RCP8.5 scenarios and for the 2021–2050 and 2051–2080 terms, respectively, concerning the recorded historical value, increasing the probability of flood events and damage in populations located downstream.

One of the most notable problems in the Atacama desert is the low occurrence of rainfall, which leads to a shortage of surface and groundwater for different users in the region. Therefore, the task of carrying out new exploration studies of potential groundwater zones (GWPZs) is of vital importance for decision-makers in water resources. The main objective of this research is to determine potential sources of groundwater using a Multi-Criteria Decision-Making technique with remote sensors. A method of exploration using the Analytical Hierarchy Process (AHP) techniques applied to remote sensing data is provided. The AHP method allows calculating the influence of multiple factors, and along with the GIS environment, a map of groundwater exploitation potential can be produced. The results indicating GWPZs showed four classifications of groundwater potential. The distribution shows 15.02%, 23.93%, 59.80%, and 1.25% of the total area with high, moderate, low, and very low potential, respectively. The results were validated with existing wells in the study area, offering an acceptance of 86.9%. This reveals the effectiveness and accuracy of the AHP-based GIS approach as a strategy for analyzing groundwater potential in arid zones. Similarly, the tested high GWP areas are helpful for the development and management of water resources in the Caplina basin.

Accurately estimating and forecasting evapotranspiration is one of the most important tasks to strengthen water resource management, especially in desert areas such as La Yarada, Tacna, Peru, a region located at the head of the Atacama Desert. In this study, we used temperature, humidity, wind speed, air pressure, and solar radiation from a local weather station to forecast potential evapotranspiration (ETo) using machine learning. The Feedforward Neural Network (Multi-Layered Perceptron) algorithm for prediction was used under two approaches: “direct” and “indirect”. In the first one, the ETo is predicted based on historical records, and the second one predicts the climate variables upon which the ETo calculation depends, for which the Penman-Monteith, Hargreaves-Samani, Ritchie, and Turc equations were used. The results were evaluated using statistical criteria to calculate errors, showing remarkable precision, predicting up to 300 days of ETo. Comparing the performance of the approaches and the machine learning used, the results obtained indicate that, despite the similar performance of the two proposed approaches, the indirect approach provides better ETo forecasting capabilities for longer time intervals than the direct approach, whose values of the corresponding metrics are MAE = 0.033, MSE = 0.002, RMSE = 0.043 and RAE = 0.016.

Groundwater constitutes one of the main sources used to satisfy the water demands of the different users located in a basin. Current groundwater pumping rates in many cases exceed natural recharge, resulting in the overexploitation of aquifers and the deterioration of water quality. Consequently, many aquifer systems in the world have applied and adapted policies to manage the use of groundwater. In this article, we investigate the impacts of groundwater management policies on the Caplina aquifer located in the Atacama Desert, Peru. To evaluate these impacts, we review policies and regulations implemented during the last 40 years. Likewise, more than 25 scientific investigations that were carried out in this aquifer are reviewed and analyzed to understand its hydrodynamics and hydrochemistry, as well as the impact of climate change, among other aspects. The results, based on scientific evidence, show that the current and future conditions of the groundwater of the Caplina aquifer are not sustainable, and likewise, public policies are not effective for reversing this situation. This leads the aquifer system to a situation in which there is a quality degradation of the water, to a point that may be irreversible.