Spray sprinklers enable to operate at low pressures (<103 kPa) in self-propelled irrigation machines. A number of experiments were performed to characterize the water distribution pattern of an isolated rotator spray plate sprinkler operating at very low pressure under different experimental conditions. The experiments were performed under two pressures (69 kPa and 103 kPa) and in calm and windy conditions. The energy losses due to the impact of the out-going jet with the sprinkler plate were measured using an optical technique. The adequacy to reproduce the measured water distribution pattern under calm conditions of two drop size distribution models was evaluated. A ballistic model was used to simulate the water distribution pattern under wind conditions evaluating three different drag models: (1) considering solid spherical drops; (2) a conventional model based on wind velocity and direction distortion pattern, and (3) a new drag coefficient model independent of wind speed. The energy losses measured with the optical method range from 20% to 60% from higher to lower nozzle sizes, respectively, for both evaluated working pressures analyzing over 16,500 droplets. For the drop size distribution selected, Weibull accurately reproduced the water application with a maximum root mean square error (RMSE) of 19%. Up to 28% of the RMSE could be decreased using the wind-independent drag coefficient model with respect to the conventional model; the difference with respect to the spherical model was 4%.

The estimation of the hydraulic parameters of an aquifer such as the hydraulic conductivity is somehow complicated due to its heterogeneity, on the other hand field and laboratory tests are both time consuming and costly. The use of geostatistical-based techniques for data assimilation could represent an alternative tool that allows the use of space-time aquifer behaviour to characterize hydraulic conductivity heterogeneity. In this paper, a spatiotemporal bivariate methodology was implemented combining historical hydraulic head data with hydraulic conductivity sparse data in order to obtain an estimate of the spatial distribution of the latter variable. This approach takes advantage of the correlation between the hydraulic conductivity (K) and the hydraulic head (H) behaviour through time. In order to evaluate this approach, a synthetic experiment was constructed through a transitory numerical flow-model that simulates hydraulic head values in a horizontally-heterogeneous aquifer. Geostatistical tools were used to describe the correlation between simulated spatiotemporal data of hydraulic head and the spatial distribution of the hydraulic conductivity in a group of model nodes. Subsequently, the Kalman filter was used to estimate the hydraulic conductivity values at nonsampled sites. The results showed acceptable differences between estimated and synthetic hydraulic conductivity data, with low estimate error variances (predominating the 1 m2/day2 value for K for all the cases, however, the smallest number of cells with values above 2 m2/day2 correspond to the bivariate spatiotemporal case) and the best agreement between the estimated errors and the selected model variance (SMSE values of 0.574 and 0.469) were found for the bivariate cases, which suggests that the implemented methodology could be used for reducing calibration efforts, particularly when the hydraulic parameters data are scarce.

The increasing population demands a greater quantity of food. In order to satisfy the world’s demand, one of the main challenges worldwide consists of modernizing the current irrigation systems. This research shows an experience carried out in a modernized irrigation module in Central-North Mexico following these objectives: to evaluate the impact of the modernization of the irrigation module, to analyze the agricultural productivity, and to assess a group of parameters related with the agricultural production (system conduction and distribution efficiencies, water productivity, among others) and the water volumes after and before the modernization. After a drought period, a methodology was performed in commercial parcels in 2013 to increase the yield of different crops. Some of the activities were: soil leveling, estimation of the soil properties (field capacity, wilting point, bulk density, pH, and organic matter), optimum fertilization applications, use of a model to scheduling irrigation, measure volumes extracted at the parcel level. With the modernization and the method used, around 1800 and 2000 m³ ha–1 were saved with respect to the initial granted volume by the Comisión Nacional del Agua and increase in the global efficiency was also achieved (from 55% to 85%). All crop yields increased, i.e., for corn from 2.5 kg/m³ to 3.8 kg/m³. The impact of modernization accompanied with an effective operation allowed a significant increase of the crop yield and water productivity. Despite a controlled distribution of water being carried out, future research should contemplate free water demand scenarios and automation irrigation for improving the module operation.

Infiltration estimation is made by tests such as concentric cylinders, which are prone to errors, such as the lateral movement under the ring. Several possibilities have been developed over the last decades to compensate these errors, which are based on physical, electronic, and mathematical principles. In this research, two approaches are proposed to measure the water infiltration rate in a silty loam soil by means of the mass values of a lysimeter weighing under rainfall conditions and different moisture contents. Based on the fact that with the lysimeter it is possible to determine acting soil flows very precisely, then with the help of mass conservation and assuming a downward vertical movement, 12 rain events were analyzed. In addition, it was possible to monitor the behavior of soil moisture and to establish the content at field capacity from the values of the weighing lysimeter, from which both approach are based. The infiltration rate of these events showed a variable rate at the beginning of the rainfall until reaching a maximum, to descend to a stable or basic rate. This basic infiltration rate was 1.49 ± 0.36 mm/h, and this is because soils with fine textures have reported low infiltration capacity. Four empirical or semi-empirical models of infiltration were calibrated with the values obtained with our approaches, showing a better fit with the Horton’s model.

The quantity and quality of the supply of fresh water to households, commercial areas, small industries, green spaces irrigation and public and private institutions in large cities face challenges from the supply sources availability and suitable distribution network performance to the full satisfaction of the established drinking water guidelines. In Mexico, the main source of water comes from groundwater. Most of the Mexican aquifers are located in arid and semi-arid weather conditions. The groundwater’s physical–chemical properties are closely related to geology. This study was carried out at the north-central part of the country in which igneous and sedimentary rocks predominate, with high calcium carbonate (CaCO3) concentrations. The accumulation of CaCO3 in the pipelines is also known as scale deposit that decreases the fluid flow, causing a deficiency in the water supply. The main objectives of this study were determining the physical–chemical groundwater parameters and saturation indexes injected into the drinking water networks and characterizing the scale deposits by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicate that the scale deposits are mainly calcium carbonate and silica oxide crystals, caused by the water aggressiveness according to the saturation indexes and the lack of control over the saturation pH.