Groundwater is the main source of water in arid cities where precipitations are low and not evenly distributed. The combined impact of climate variability and intensive human activities has caused a substantial decline in groundwater levels. Understanding the response of groundwater levels to meteorological and anthropogenic factors is a key step to propose water management alternatives. Meteorological and groundwater data were used to design a multi-step approach to assess the influential factors on the groundwater system in the City of Chihuahua, Mexico. The analysis of historical groundwater levels and climate showed a clear increase in meteorological drought, as well as a groundwater abstraction trend since 1986. Rainfall, groundwater recharge, and groundwater level displayed a significant decrease. Overall, the groundwater depth is continuously increasing with a strong correlation with groundwater abstraction. Despite having a significant trend, the changes in land-cover, groundwater recharge, and meteorological drought were not the main factors inducing the decreased level of water in the aquifer. The continuous abstraction of groundwater from 1986 to 2010 has led to a depletion of groundwater levels from 32 to 92 m. The findings of this study lay a foundation for future water resource management in the study area.
In intermittent drinking water distribution systems, large volumes of the water are wasted due to leaks in the distribution networks. Similarly, user service is not always satisfied in the time required to fill the storage, nor with sufficient pressure. Hence the importance of this study. Measuring the variability of pressure in the distribution network and determining the factors that influence the definition of a sufficient minimum hours of service, is a first step to change to a continuous service 24/7, in order to minimize the volumes of lost water and meet demand. In total, 347 pressure sensors were placed in a network to detect changes in pressure and obtain data for 3 years. This study presents a new approach to determine the operating policy of the operating agency that provides the service intermittently. Two objectives are pursued: pressure variability – to minimize leaks – and define the minimum hours of service. The analysis was performed using multivariate statistical techniques, including principal component analysis, correlation matrix and ANOVAs, to explore the association between objectives. The results obtained show that the pressure distribution has a Gaussian behavior and that the hours of service have a Poisson distribution.
Cities in developing countries that do not consider water resources as the basis for sustainable growth usually accept intermittent water supply (IWS) as the alternative to satisfy the demand of the population. Networks designed as constant water supply (CWS) operated as IWS hinder a safe and reliable water supply; thus, feasible alternatives to return the operation to CWS are required. This paper presents a methodology based flow/pressure control to accomplish an efficient transformation from an IWS sector to a CWS in the City of Chihuahua, Mexico. The management of pressure at sector entrance and critical supply points leads to successful improvement of service, ensuring water availability with adequate pressure at the peak of demand, as well as reducing the supply of water volume by 58% compared to the sector operated in IWS. The methodology allowed the improvement of decision-making and operating policy for the water operating agency (WOA), fixing service deficiency, avoiding the loss of water volumes, and maintaining competent management control. Nonetheless, resistance to the transition of using automation and setting the volume/pressure consumption based on reliable data persists. The change process will be successful to the extent that the WOA efficiently channels the participation of the personnel.
Maintaining a constant flow in a potable water distribution hydraulic system is challenging due to fluctuations caused by changes in user demand and seasonal factors. This study aimed to calculate the coefficients and curves of hourly and daily variation of water demand in the water distribution system of Chihuahua. It is crucial to understand the hydraulic system's behavior during peak demands and assess its capacity. The methodology involved calculating coefficients and curves of variation of demand based on flow data measured at the inlet of various hydrometric sectors using flanged electromagnetic flowmeters of various diameters and models. The results showed that the variation curves and coefficients of water demand are valuable tools for modeling, designing, and operating water networks. Incorporating these curves into hydraulic simulations during the planning and design stage can improve the accuracy of these models and better reflect the network's actual behavior. The proposed method is suitable for application in cities with similar demographic and social characteristics. The study concludes that accurate supply area information for hydrometric sectors is essential in constructing the curves and coefficients of demand variation, which can lead to opportunities for improving water service by informing more effective network design and operation.
A sustainable drinking water system is essential to ensure the availability of water. Efficient management is developed by maintaining a positive and continuous pressure. However, in developing countries, the conception is that a constant water supply is unsustainable and the preferred alternative is to modify to an intermittent water supply. In this paper, a methodology for gradually transforming several sectors to a constant supply to decrease the quantity of water supplied is developed. Network sectorization and pressure management were achieved, indicating that the operation of 19% of the households under this methodology generates 24% of the water-saving of the city.
Mineral scaling and corrosion pose significant challenges in groundwater distribution, increasing hydraulic resistance, reducing flow rates, and raising operational costs. Magnetic water treatment (MWT) has gained attention as a non-chemical method to mitigate scale formation by promoting the transformation of calcite, a hard and adherent CaCO3 polymorph, into aragonite, a softer and less adherent form. In Chihuahua, Mexico, mineral scaling has disrupted the drinking water distribution system, reducing flow and impairing service. This study evaluates MWT’s potential to mitigate scaling by analyzing magnetized water treated under various MWT configurations. Comparative analyses were conducted via XRD and SEM to assess changes in calcium carbonate polymorphs. Finite element method (FEM) simulations in COMSOL Multiphysics 6.0 were used to evaluate the magnetic field distribution. The results show no systematic trend in CaCO3 polymorph transformation following MWT exposure, and FEM simulations indicate negligible magnetic field gradients in certain configurations. These findings highlight the critical role of optimizing magnetic field alignment and gradient strength. Future research should refine MWT configurations and incorporate real-time monitoring to enhance its effectiveness in scale prevention.