Recharge Program Research Articles

Simulation of Groundwater Dissolved Organic Carbon in Yufu River Basin during Artificial Recharge: Improving through the SWAT-MODFLOW-RT3D Reaction Module

To keep groundwater levels stable, Jinan’s government has implemented several water management measures. However, considerable volumes of dissolved organic carbon (DOC) can enter groundwater via water exchange, impacting groundwater stability. In this study, a SWAT-MODFLOW-RT3D model designed specifically for the Yufu River Basin is developed, and part of the code of the RT3D module is modified to simulate changes in DOC concentrations in groundwater under different artificial recharge scenarios. The ultimate objective is to offer valuable insights into the effective management of water resources in the designated study region. The modified SWAT-MODFLOW-RT3D model simulates the variations of DOC concentration in groundwater under three artificial recharge scenarios, which are (a) recharged by Yellow River water; (b) recharged by Yangtze River water; and (c) recharged by Yangtze River and Yellow River water. The study shows that the main source of groundwater DOC in the basin is exogenous water. The distribution of DOC concentration in groundwater in the basin shows obvious spatial variations due to the influence of infiltration of surface water. The area near the upstream riverbank is the earliest to be affected. With the prolongation of the artificial recharge period, the DOC concentration in groundwater gradually rises from upstream to downstream, and from both sides of the riverbank to the surrounding area. By 2030, the maximum level of DOC in the basin will exceed 6.20 mg/l. The Yellow River water recharge scenario provides more groundwater recharge and less DOC input than the other two scenarios. The findings of this study indicate that particularly when recharge water supplies are enhanced with organic carbon, DOC concentrations in groundwater may alter dramatically during artificial recharge. This coupled modeling analysis is critical for assessing the impact of recharge water on groundwater quality to guide subsequent recharge programs.

Spatio-temporal variation of depth to groundwater level and its driving factors in arid and semi-arid regions of India

Climate change and increasing anthropogenic activities, such as over-exploitation of groundwater, are exerting unavoidable stress on groundwater resources. This study investigated the spatio-temporal variation of depth to groundwater level (DGWL) and the impacts of climatic (precipitation, maximum temperature, and minimum temperature) and anthropogenic (gross district product (GDP), population, and net irrigated area (NIA)) variables on DGWL during 1994–2020. The study considered DGWL in 113 observation wells and piezometers located in arid western plains (Barmer and Jodhpur districts) and semi-arid eastern plains (Jaipur, Ajmer, Dausa, and Tonk districts) of Rajasthan State, India. Statistical methods were employed to examine the annual and seasonal patterns of DGWL, and the generalized additive model (GAM) was used to determine the impacts of climatic and anthropogenic variables on DGWL. During 1994–2020, except for Barmer District, where the mean annual DGWL was almost constant (around 26.50 m), all other districts exhibited increase in DGWL, with Ajmer District experiencing the most increase. The results also revealed that 36 observation wells and piezometers showed a statistically significant annual increasing trend in DGWL and 34 observation wells and piezometers exhibited a statistically significant decreasing trend in DGWL. Similarly, 32 observation wells and piezometers showed an statistically significant increasing trend and 37 observation wells and piezometers showed a statistically significant decreasing trend in winter; 33 observation wells and piezometers indicated a statistically significant increasing trend and 34 had a statistically significant decreasing trend in post-monsoon; 35 observation wells and piezometers exhibited a statistically significant increasing trend and 32 observation wells and piezometers showed a statistically significant decreasing trend in pre-monsoon; and 36 observation wells and piezometers reflected a statistically significant increasing trend and 30 observation wells and piezometers reflected a statistically significant decreasing trend in monsoon. Interestingly, most of the observation wells and piezometers with increasing trends of DGWL were located in Dausa and Jaipur districts. Furthermore, the GAM analysis revealed that climatic variables, such as precipitation, significantly affected DGWL in Barmer District, and DGWL in all other districts was influenced by anthropogenic variables, including GDP, NIA, and population. As a result, stringent regulations should be implemented to curb excessive groundwater extraction, manage agricultural water demand, initiate proactive aquifer recharge programs, and strengthen sustainable management in these water-scarce regions.

Using Remote Sensing to Assess the Vegetation Cover of a Protected Salt Marsh Subjected to Artificial Recharge and Groundwater Abstractions during the Period 1925–2022 (Alicante, SE Spain)

The Agua Amarga salt marsh has been subjected to artificial seawater recharge on its surface during the period 1925–1969 for industrial purposes (saltwork activity) and from 2008 to present to compensate for coastal groundwater abstraction to supply Alicante desalination plants. This groundwater abstraction has caused piezometric depletion in the coastal aquifer connected to the protected salt marsh. The seawater recharge program also involved vegetation monitoring to control the impact on the salt marsh ecosystem, allowing data to be collected about the halophyte vegetation species growing in the salt marsh (Arthrocnemum macrostachyum, Sarcocornia fruticosa, and Ruppia maritima, among others) from spring and autumn field surveys. In this work, vegetation development is assessed with remote sensing for the period 1929–2022 using images with visible and near-infrared spectral resolution. Different spectral indices (NDVI, BI, and NDWI) and classification algorithms (random forest) are used to calculate the vegetation cover. Field data are employed to evaluate the protocols and compare the results, showing a 46% decrease caused by the salt works and a 50% increase as a result of natural evolution and artificial recharge. The spread of Phragmites australis is also addressed by comparing LiDAR data with field monitoring, showing an increase of 12% during the period 2005–2023. The advantages and complementarity of field monitoring and remote sensing information are explained.

Agent-based modeling to assess decentralized water systems: Micro-trading rainwater for aquifer recharge

Decentralized aquifer recharge programs are an alternative to centralized stormwater aquifer recharge systems and can improve groundwater tables in urban areas. In a decentralized aquifer recharge program, households and property-owners collect and store rainwater from rooftops and replenish aquifers through small gravity-fed recharge wells. This research presents a micro-trading rainwater for aquifer recharge (MRAR) system as a decentralized peer-to-peer water market that can recharge groundwater resources. Through a decentralized water market, households act as prosumers who collect and sell rainwater to consumer households and convey traded water via a shared aquifer. This research develops an agent-based modeling framework as an approach to evaluate the performance of a MRAR system to replenish groundwater resources and reduce energy required to pump water. Agents represent (1) prosumers that collect rainwater, sell rainwater to consumers, and replenish the groundwater system through dry wells, and (2) consumers that exert irrigation demands, buy rainwater from prosumers, and pump water from the groundwater system. The agent-based model is coupled with a groundwater flow model to evaluate the effects of micro-trading on groundwater resources. The agent-based modeling framework is applied for a virtual city to assess the performance of a MRAR system for scenarios that vary in the ratio of consumers to prosumers, location of prosumers and consumers, and aquifer properties. Model outcomes demonstrate the optimal ratio of consumers to prosumers based on the volume of traded water, improvements in groundwater head, and improvements in unit energy of water. Findings demonstrate that the optimal ratio of consumers to prosumers is consistent across different values for hydraulic conductivity. The location of prosumer and consumer households affects the unit energy of water and has a negligible effect on the groundwater table and total energy consumed to pump water. This manuscript proposes and demonstrates MRAR as a new decentralized water system and provides a modeling approach to assess the performance of a MRAR system to improve urban groundwater resources.

Demonstration of Managed Aquifer Recharge in a Coastal Plain Aquifer: Lessons Learned

The sustainable water initiative for tomorrow (SWIFT) is a 378,000 m3 /day (100 MGD) managed aquifer recharge (MAR) program designed by the Hampton Roads Sanitation District (HRSD) to rehabilitate the Potomac Aquifer System (PAS) in the Coastal Plain of Eastern Virginia. Groundwater is a primary water source in Eastern Virginia with over 93% of reported use derived from the PAS. Starting in May 2018, HRSD has operated a 3780 m3 /day (1.0MGD) MAR demonstration facility at the SWIFT Research Center (SWIFT-RC) in Suffolk, Virginia. The primary aim of the SWIFT-RC is to demonstrate, at a meaningful scale, the feasibility of MAR using deep well recharge into confined PAS hydrostratigraphic unit. The SWIFT-RC employs advanced water treatment technology to bring secondary effluent from an HRSD wastewater treatment plant to drinking water standards. Lessons learned include the evaluation and selection of a multiple barrier carbon-based treatment system to ensure water quality and maintain geochemical compatibility between MAR water and native groundwater, and the evaluation and selection of aluminum chlorohydrate for stabilizing aquifer clays immediately around the well to accept the fresher recharge water. The distribution of flow in the SWIFT-RC multiscreen recharge well and associated well injectivity were variable with time resulting from changing conditions in the well. Dynamic recharge well performance was quantified through the combined analysis of intrinsic and artificial tracer transport, in situ flowmeter testing, and water level analysis. Monitoring well nests and a depth-discrete sampling system supported a robust sampling plan to analyze chemical transport and attenuation in SWIFT-RC groundwater.

Groundwater Recharge to Address Integrated Groundwater and Surface Waters

The Eastern Snake Plain Aquifer (ESPA) Recharge Program aims to recharge an average of 250,000 AFY to mitigate the effects of groundwater pumping on surface water resources and, in doing so, to reduce conflicts between surface and groundwater users. The Idaho Water Resources Board (IWRB) partners with canal and irrigation companies to use IWRB’s surface water rights to conduct aquifer recharge through in- and off-canal seepage and direct injection wells. The canal and irrigation companies are paid by IWRB to use their canals and property for recharge sites. From 2014 to 2019, the program achieved 249,028 AFY of average recharge per year. The ESPA Recharge Program serves as a good example of a statewide recharge program that addresses challenges in managing highly connected groundwater and surface water. Moreover, it illustrates the incentives that can emerge for joint management of groundwater and surface water based on legal regimes that integrate the two. The ESPA Recharge Program particularly benefited from its centralized structure, with one state agency, IWRB, given sole control of implementing the recharge program. Nevertheless, the program faces some future obstacles, namely, in securing long-term funding, building out conveyance capacity to transport water to recharge sites during wet years, and modeling groundwater resources adequately.

Incentivizing Groundwater Recharge in the Pajaro Valley Through Recharge Net Metering (ReNeM)

Decades of groundwater overuse in the Pajaro Valley have contributed to an estimated groundwater overdraft of 12,100 acre-feet per year (AFY) in the basin. In response, the Pajaro Valley Water Management Agency adopted a pilot groundwater recharge program, called Recharge Net Metering (ReNeM). ReNeM encourages development of infiltration projects on private or public land by offering a rebate on groundwater pumping fees based on the net increase in infiltration. The rebate uses the following equation: Rebate = W50x (Inftot − Infinc), where Infinc is the incidental infiltration that would have occurred without the project, Inftot is total measured infiltration, and W50 represents the proportion (50%) of the pumping fee assessed to the landowner based on location. The goal of Pajaro Valley’s ReNeM pilot program is to infiltrate 1,000 AFY to the aquifer by creating and operating infiltration projects at multiple sites. This effort will help reduce groundwater overdraft and associated undesirable consequences (seawater intrusion, disconnection with surface water, and degradation to water quality). This case study analyzes the local conditions and institutions that make the ReNeM pilot program feasible, including previously established groundwater pumping fees, metered wells, and the existence of third-party certifiers able to verify the results of project sites. The ReNeM pilot has enabled increased recharge by creating new incentives that have drawn PV Water, landowners, and tenant farmers to develop recharge projects. The ReNeM pilot is the first and thus far only application of this approach, but the methods used by ReNeM may have potential applicability elsewhere. This potential will hinge on whether the pilot can prove the effectiveness of the rebate scheme and demonstrate measurable benefits in the Pajaro Valley.

Groundwater Recharge to Address Seawater Intrusion and Supply in an Urban Coastal Aquifer

The Orange County Water District (OCWD) was created in 1933 by the California Legislature and tasked with managing water resources in Orange County. As a part of its strategy to fight seawater intrusion and guarantee a reliable groundwater supply in the basin, OCWD built a recycled wastewater facility that treats wastewater received from the Orange County Sanitation District and recharges the water into the basin through injection wells and infiltration ponds. OCWD’s first recycled wastewater facility, Water Factory 21, began operating in 1975 and was replaced in 2008 by the Groundwater Replenishment System (GWRS). Recharged water not serving as a barrier for seawater instruction is pumped by local water districts and municipalities (referred to as “producers”), who pay a pumping fee to OCWD. Water provided by GWRS is both more reliable and less expensive for the producers than water acquired from other sources, including imported surface water. In responding to the recognized threat of seawater intrusion, OCWD owes its success to creatively enabling recharge through the development of novel source water. OCWD’s broad purview and authority to manage groundwater, combined with its effective implementation and long-term stewardship of the recharge program as it has evolved over many years, have enabled innovation in MAR using treated wastewater.

Using Analytical Hierarchy Process and Multi-Influencing Factors to Map Groundwater Recharge Zones in a Semi-Arid Mediterranean Coastal Aquifer

Mapping groundwater recharge zones (GWRZs) is essential for planning artificial recharge programs to mitigate groundwater decline and saltwater intrusion into coastal aquifers. We applied two multi-criteria decision-making approaches, namely the analytical hierarchy process (AHP) and the multi-influencing factors (MIF), to map GWRZs in the Korba aquifer in northeastern Tunisia. GWRZ results from the AHP indicate that the majority (69%) of the area can be classified as very good and good for groundwater recharge. The MIF results suggest larger (80.7%) very good and good GWRZs. The GWRZ maps improve groundwater balance calculations by providing estimates of recharge-precipitation ratios to quantify percolation. Lithology, land use/cover and slope were the most sensitive parameters followed by geomorphology, lineament density, rainfall, drainage density and soil type. The AHP approach produced relatively more accurate results than the MIF technique based on correlation of the obtained GWRZs with groundwater well discharge data from 20 wells across the study area. The accuracy of the approaches ultimately depends on the classification criteria, mean rating score and weights assigned to the thematic layers. Nonetheless, the GWRZ maps suggest that there is ample opportunity to implement aquifer recharge programs to reduce groundwater stress in the Korba aquifer.

PROFESSIONAL COMPETENCE DEVELOPMENT: A PHENOMENOLOGICAL STUDY OF EFL TEACHERS AT SMA NEGERI 1

Teacher’s professional competence development becomes very important in the general area of study of education, it is probably because the professional competence development of the teacher plays an important role in their performance in teaching and the interaction with the students and other members of the school community. So, the problem statement of this research are: (i) What are the EFL teacher’s at SMA Negeri 1 Parepare Perspectives on the meaning of professional competence development. The research applying a qualitative descriptive method in the form of a phenomenological study approach. The findings indicate that (i) EFL teacher’s perspectives on the meaning of professional competence development in SMA Negeri 1 Parepare are: English teacher’s professional competence development is very necessary and very helpful it feels like a re-fresh and recharge program, English teacher’s professional competence development is very influential in increasing them self-confidence at teaching and influential to the teaching quality for both professional and pedagogical competence, Professional competence development very much helped to improve their professional and pedagogical competence, EFL teacher’s professional competence development has very good and a lot of positive effects for their profession as a teacher, EFL teacher’s professional competence development is really feel indeed greatly help improve their quality in teaching.

A pilot study of a brief intervention program (RECHARGE) to reduce sleep-wake and circadian rhythm disturbances in youth being treated for depression

Aim: Sleep-wake and circadian rhythm disturbances are linked to the emergence and persistence of depression in youth. However, few youth-specific interventions have been developed to address this in clinical settings. We aimed to test the efficacy of a novel program targeted at sleep-wake and circadian rhythm problems in youth with depression. Methods: Adolescents and young adults with depression and sleep-wake disturbances were invited to join the 8-week RECHARGE program. Outcomes of interest were pre- to postintervention changes in self-reported sleep-wake patterns and circadian preference, actigraphy recordings of circadian sleep rhythms, and depressive symptoms. Results: 10 individuals completed the RECHARGE program showed modest improvements in self-reported sleep-wake patterns and circadian rhythmicity as measured by actigraphy; however these did not explain a significant portion of the variance in post-intervention depression scores. Conclusions: Modest trends for some sleep-wake and circadian parameters indicate that future investigation of a modified RECHARGE program is merited.

Reviving the Ganges Water Machine: Accelerating surface water and groundwater interactions in the Ramganga sub-basin

Reviving the Ganges Water Machine (GWM), coined 40years ago, is the most opportune solution for mitigating the impacts of recurrent droughts and floods in the Ganges River Basin in South Asia. GWM create subsurface storage (SSS) by pumping more groundwater from the aquifers before the monsoon for irrigation and other uses and recharge it during the monsoon. The present study uses fully processed and physically based numerical models, MODFLOW and SWAT, in a semi-coupled modelling framework to examine the technical feasibility of recharging the SSS. The aquifer was simulated as a two-layer system using hydrogeological and groundwater data, model was calibrated from 1999 to 2005 and validated from 2006 to 2010. It assesses the impacts of gradual increase of SSS in 10years from the base year 2010 under two scenarios (increased rainfall or controlled pumping and recharge) to meet a potential unmet demand of 1.68billion cubic meters (Bm3) in the Ramganga sub-basin with an area of 18,668km2. The results show that 3–4m of subsurface storage can be created by groundwater pumping of 0.25Bm3/year by 2020. Under the controlled pumping and recharge scenario, groundwater recharge and river seepage could increase by 14% (4.21–4.80Bm3) and 31% (1.10–1.44Bm3), respectively. However, baseflow will decrease by 30% (0.18–0.12Bm3) over the same time period. The results also show that recharge increased 44% (4.21–6.05Bm3) under an increased rainfall scenario. Simultaneously, river seepage and baseflows would increase 36% (1.10–1.14Bm3) and 11% (0.18–0.20Bm3), respectively. A well-designed managed aquifer recharge program is required to eliminate the negative impact of river flows in the low flow season.

Artificial recharge of the phreatic aquifer in the upper Friuli plain, Italy, by a large infiltration basin

To cope with the general reduction of water availability and increase the subsurface storage of high-quality surficial waters, an artificial recharge project is ongoing in northern Italy within the WARBO LIFE+ Project funded by EU. WARBO is aimed at implementing large-scale use of artificial recharge in Italy where water directives still strongly limit its application. In this context, the Mereto recharge site was selected in the upper Fruili plain where the water availability is guaranteed during winter period by the Tagliamento and Ledra Rivers. An infiltration basin, about 5.5 m deep and 45 × 7 m2 wide, was built at Mereto in the early 2000s but the possibility of implementing the recharge has been allowed only very recently. The site is characterized by an elevation of 105 m asl and the depth to the groundwater table averages 50 m. Below a few meter-thick organic soil, the aquifer is composed by coarse deposits with an estimated thickness of 100 m and an average vertical hydraulic conductivity on the order of 10−4 m/s. A ~0.1 m3/s infiltration flow has been preliminary estimated (corresponding to an infiltration rate of 60 cm/h). Geophysical investigations (electrical resistivity tomography, high-resolution seismic surveys) together with infiltration and pumping tests have been carried out to characterize the vadose zone and the unconfined aquifer in the study area. Functional approaches and three-dimensional (3D) Finite Element numerical computations have been used to predict the effect of the artificial recharge. The results of these investigations will greatly reduce the hydrogeological knowledge gaps and will be used to fine tune the recharge program and to define the monitoring concept. This contribution aims to provide a methodology for the implementation of managed aquifer recharge programs using existing structures.

Towards a Managed Aquifer Recharge strategy for Gujarat, India: An economist’s dialogue with hydro-geologists

• Groundwater overdraft has emerged as a major crisis for Gujarat in Western India. • Hydro-geologists favoured a recharge strategy limited by average annual surplus runoff available. • Incorporating economic thinking justified a far more ambitious recharge program. • Energy savings and reduced carbon footprint make aquifer storage attractive. • Synthesis of hydrology and economics needed for superior policy recommendations. Gujarat state in Western India exemplifies all challenges of an agrarian economy founded on groundwater overexploitation sustained over decades by perverse energy subsidies. Major consequences are: secular decline in groundwater levels, deterioration of groundwater quality, rising energy cost of pumping, soaring carbon footprint of agriculture and growing financial burden of energy subsidies. In 2009, Government of Gujarat asked the present author, an economist, to chair a Taskforce of senior hydro-geologists and civil engineers to develop and recommend a Managed Aquifer Recharge (MAR) strategy for the state. This paper summarizes the recommended strategy and its underlying logic. It also describes the imperfect fusion of socio-economic and hydro-geologic perspectives that occurred in course of the working of the Taskforce and highlights the need for trans-disciplinary perspectives on groundwater governance.

Emerging Contaminant Sources and Fate in Recharged Treated Wastewater, Lake Havasu City, Arizona

In 2008, Lake Havasu City, Arizona, began a treated wastewater subsurface recharge program at its North Regional Wastewater Treatment Plant (NRP) to store treated wastewater, which is planned to be seasonally recovered for irrigation during the summer months. As a proactive measure, the city decided to monitor a suite of pharmaceuticals and other emerging contaminants (PECs) along with required regulatory constituents, e.g., nitrate. Potential contributing sources of PECs throughout the water system were identified, resulting in only six constituents detected in the untreated drinking water and treated drinking water, all at concentrations less than 50 ng/L. Thirty-three of 40 PECs analyzed were identified in the city9s treated wastewater streams, with concentrations ranging from just above the detection level to 9000 ng/L (pseudoephedrine), clearly showing the dominating local urban use of these compounds. NRP treated wastewater is recharged via vadose zone injection wells. It migrates through alluvial fans sediments, some containing interstitial clays, forming a water mound and blending with groundwater of the Colorado River Aquifer. Sixteen of 33 PECs present in the NRP treated wastewater have concentrations above detection limits (>10 ng/L) within 150 m (492 ft) of the injection wells. Six PECs (sulfamethoxazole, carbamazepine, primidone, phenytoin, N,N-diethyl-meta-toluamide [DEET], and meprobamate) remained above their respective detection limit in monitoring wells that penetrate sediments largely free of clay more than 560 m (1,840 ft) away from the injection wells.

Spatial variation in drainage characteristics and geomorphic instantaneous unit hydrograph (GIUH); implications for watershed management—A case study of the Varada River basin, Northern Karnataka

Abstract Geomorphological characteristics can be treated as signatures of hydrological responses. Geomorphologic instantaneous unit hydrograph (GIUH) is of utmost use in planning watershed management programs on a broad scale in absence of hydrologic data. Fifth order basins from different agroclimatic zones in the Varada River basin were selected to understand the spatial variation in drainage characteristics. These sub-basins show significant differences in their morphometric properties such as basin area, drainage density, bifurcation ratio, circularity ratio, constant of channel maintenance etc. These differences reflect variation in the hydrological process and geomorphologic instantaneous unit hydrograph (GIUH) of different sub-basins and can be used to understand watershed management aspects. Fifth order sub-basin in the Southern Transition agroclimatic zone is potential for artificial recharge programs. Sub-basins in the Hilly non-forest zone on the north are ideal for surface water storage like tank development program while Forested Hilly zone on the north are environmentally sensitive and prone to erosion.

TOC Removal from Tertiary Effluent in the Chino Basin Recycled Water Groundwater Recharge Program: Results from the Monitoring Program

TOC Removal from Tertiary Effluent in the Chino Basin Recycled Water Groundwater Recharge Program: Results from the Monitoring Program

Excess air during aquifer storage and recovery in an arid basin (Las Vegas Valley, USA)

The Las Vegas Valley Water District in Nevada, USA, has operated an artificial recharge (AR) program since 1989. In summer 2001, observations of gas exsolving from tap water prompted a study that revealed total dissolved gas (TDG) pressures approaching 2 atm with a gas composition that it is predominantly air. Measurements of TDG pressure at well heads and in the distribution system indicated two potential mechanisms for elevated TDG pressures: (1) air entrainment during AR operations, and (2) temperature changes between the winter recharge season and the summer withdrawal season. Air entrainment during pumping was investigated by intentionally allowing the forebay (upstream reservoir) of a large pumping station to drawdown to the point of vortex formation. This resulted in up to a 0.7 atm increase in TDG pressure. In general, the solubility of gases in water decreases as the temperature increases. In the Las Vegas Valley, water that acquired a modest amount of dissolved gas during winter artificial recharge operations experienced an increase in dissolved gas pressure (0.04 atm/°C) as the water warmed in the subsurface. A combination of air entrainment during AR operations and its amplification by temperature increase after recharge can account for most of the observed amounts of excess gas at this site.

Optimal Pump and Recharge Management Model for Nitrate Removal in the Warren Groundwater Basin, California

The town of Yucca Valley located in the southwest part of the Mojave Desert in southern California relies on groundwater pumping from the Warren groundwater basin as its sole source of water supply. This significant dependency has resulted in a large imbalance between groundwater pumpage and natural recharge, causing groundwater levels in the basin to decline more than 90 m from the late 1940s to 1994. Consequently, an artificial recharge program proposed by the Hi-Desert Water District, which provides water service to the town of Yucca Valley, was implemented for the purpose of recovering the groundwater levels; however, the rise in groundwater levels has caused nitrate ( NO3 ) concentration to increase simultaneously. The purpose of this study is to develop an optimal pump and recharge strategy for a planned conjunctive-use project to remove the high-nitrate concentration while maintaining groundwater levels at desired elevations at specified locations as well as meeting water demand. An optimization/ma...

Manejo de recursos Hidráulicos en la Cuenca de Méxicol: estado acutal y escenarios alternativos

Water management policies in the Basin of Mexico, where Mexico City and its nearly 20 million inhabitants live, are analyzed. After a brief description of how water has been managed, possible water management plans that would change water management practices in the Basin are discussed and a call is made for a change in the defensive attitude towards water taken to date. As the aquifer’s replacement cost is considered to be the proxy for the implementation of water tariffs, this is determined, based on the cost of future water sources, and found to be 0.65-0.72 USD/m3. This is twice the amount currently charged in the Federal District (0.34 USD/m3), where 45% of the City's domestic water users are found. As another alternative, the development of an artificial recharge program is also analyzed and found to be a plausible way to increase water supply at a unitary cost of 0.605 USD/m3. Despite the presence of these alternatives, it is suggested that water management in the Basin needs to change from a water supply approach to a water demand approach.