Depth-dependent Metagenome-Assembled Genomes of Agricultural Soils under Managed Aquifer Recharge

Managed aquifer recharge (MAR) has been gaining adoption within the mining industry for managing surplus water volumes and reducing the groundwater impacts of dewatering. This paper reviews MAR for mining and includes an inventory of 27 mines using or considering MAR for current or future operations. Most mines using MAR are in arid or semi-arid regions and are implementing it through infiltration basins or bore injection to manage surplus water, preserve aquifers for environmental or human benefit, or adhere to licensing that requires zero surface discharge. Surplus water volumes, hydrogeological conditions, and economics play a pivotal role in the feasibility of MAR for mining. Groundwater mounding, well clogging, and interaction between adjacent mines are common challenges. Mitigation strategies include predictive groundwater modeling, extensive monitoring programs, rotation of infiltration or injection facilities, physical and chemical treatments for clogging, and careful location for MAR facilities in relation to adjacent operations. Should water availability alternate between shortage and excess, injection bores may be used for supply, thus reducing costs and risks associated with drilling new wells. MAR, if applied strategically, also has the potential to accelerate groundwater recovery post-mine closure. The success of MAR for mining is emphasized by mines opting to increase MAR capacity alongside dewatering expansions, as well as prospective mines proposing MAR for future water requirements. Upfront planning is the key to maximizing MAR benefits. Improved information sharing could help increase awareness and uptake of MAR as an effective and sustainable mine water management tool.

Chronic exposure to environmentally-relevant sulfamethoxazole alters ammonia-oxidizing microbial communities in managed aquifer recharge systems.

Managed Aquifer Recharge (MAR) and water banking are of increasing importance to water resources management. MAR can be used to buffer against drought and changing or variable climate, as well as provide water to meet demand growth, by making use of excess surface water supplies and recycled waters. Along with hydrologic and geologic considerations, economic and policy analyses are essential to a complete analysis of MAR and water banking opportunities. The papers included in this Special Issue fill a gap in the literature by revealing the range of economic and policy considerations relevant to the development and implementation of MAR programs. They illustrate novel techniques that can be used to select MAR locations and the importance and economic viability of MAR in semi-arid to arid environments. The studies explain how MAR can be utilized to meet municipal and agricultural water demands in water-scarce regions, as well as assist in the reuse of wastewater. Some papers demonstrate how stakeholder engagement, ranging from consideration of alternatives to monitoring, and multi-disciplinary analyses to support decision-making are of high value to development and implementation of MAR programs. The approaches discussed in this collection of papers, along with the complementary and necessary hydrologic and geologic analyses, provide important inputs to water resource managers.

The European MARSOL project includes different examples of managed aquifer recharge (MAR) facilities in the Mediterranean area. A methodical characterization of the whole recharge process has been carried out to ensure that all functions and facilities are clearly comparable independent of size, budget or location. The seven selected MAR demo sites are located in two countries. Four are in Portugal—Rio Seco and Noras (Campina de Faro Aquifer), S. Bartolomeu de Messines and Cerro do Bardo (Querença-Silves) in Algarve, and three are in Spain—Llobregat (Catalonia), Santiuste and El Carracillo (Castilla y León). The systems have been defined using a form divided into four sections, including alpha-numerical data, orthophotographs, sketches and schedules. A first draft using a bibliography was reviewed by the authors, who recorded a detailed analysis and further reports to complete the characterization, as shown in several tables. The article covers MAR benchmarking serial steps for infrastructure measurements (surfaces, lengths, facilities, costs), functions categorization (transport, infiltration, treatment, restoration) and evolution in time and space (maps, sketches and calendars). MAR measuring displays contrasting interpretations depending on scale. The benchmarking process was found to be difficult to apply to seven sites with different sizes, aims, operational procedures and time scales. However, some parameters, such as mean infiltration rate, have shown their potential as management decision tools in the long term. Mediterranean areas, characterized by water supply irregularity, which is likely to be exacerbated by climate change models, can benefit from the use of MAR as a water management technique and from its diverse functions, although these objectives have not generally been attached to recharge. Null energy cost and low initial investment can also play important roles in boosting MAR development as a feasible alternative in short-term water planning.

Depletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR) system was conducted. In many cases, there are no local sources of water supply of any quality in the wadi valleys. The cost per cubic meter for supplying desalinated water is $2–5/m3 plus conveyance cost, and treated wastewater via an MAR system is $0–0.50/m3 plus conveyance cost. The wastewater reuse, indirect for potable use and direct use for irrigation, can have a zero treatment cost because it is discharged to waste in many locations. In fact, the economic loss caused by the wastewater discharge to the marine environment can be greater than the overall amortized cost to construct an MAR system, including conveyance pipelines and the operational costs of reuse in the rural environment. The MAR and associated reuse system can solve the rural water supply problem in the wadi valleys and reduce the economic losses caused by marine pollution, particularly coral reef destruction.

Assessing the efficiency of a coastal Managed Aquifer Recharge (MAR) system in Cyprus

A new workflow for assigning removal credits to assess overall performance of managed aquifer recharge (MAR)

In view of heightened climate change (CC), adaptation strategies are imperative to diminish the impacts on social and environmental assets. Two approaches are commonly used to formulate adaptation measures, namely bottom-up and top-down, each with inherited limitations. A sound bridge between both approaches is low-regret adaptive measures, which result in win-win scenarios, as they provide solutions to current pressures and contribute to building CC adaptive capacity. Managed aquifer recharge (MAR) is a term that includes a series of techniques that enhance groundwater storage for later use or environmental purposes. MAR is often mentioned in the literature as a CC adaptation measure. Nonetheless, few examples explicitly prove this point. We show through the Los Arenales MAR systems (Central Spain) that MAR is a low-regret CC adaptive measure. We evaluate a series of social and environmental challenges that MAR systems contribute to solving, as well as their attributes that diminish the expected impacts of CC in the study area. MAR in the Los Arenales groundwater body has resulted in an overall increase in groundwater levels; a reduction in groundwater pumping energy and costs and CO2 emissions; restoration of a surface water body; improvement in rural population indexes; and enhanced groundwater demand control and CC adaptive capacity through irrigation communities. To cope with CC, the Los Arenales MAR systems can be operated even if decreasing streamflow precludes the use of river water surpluses; they provide surface storage volume to mitigate flooding; and they decrease the impacts of droughts and water scarcity. This research proves that MAR is a water management tool capable of providing solutions to several pressures simultaneously in the present and future, an attribute particularly useful when dealing with adaptation gaps in developing countries, rural areas, or regions lacking long-term climatic data.

Abstract‘Multiple-use services’ (MUS) takes into account the fact that households use water for both domestic and for productive uses. This paper is the first to determine how managed aquifer recharge (MAR) systems are a form of MUS. Two cases were studied in India and in Kenya. In the Kenyan case, sand dams are the form of MAR, and in India check dams and infiltration ponds of various scales are used. Through observations, interviews, and water quality data, it is possible to describe how the communities access the water from these infrastructures in multiple ways for different uses, according to their water needs and the characteristics of the different access points. MAR involves harvesting rainwater and retaining run-off water into the dry season thus increasing the amount of available water and enabling diversification of water uses. It should therefore be considered as an option by water managers aiming to develop water resources meeting both the domestic and productive needs of communities.

Managed aquifer recharge (MAR) offers a potential innovative solution for addressing groundwater resource issues, enabling excess surface water to be stored underground for later abstraction. Given its favourable hydrogeological properties, the Pliocene sand and gravel (Crag) aquifer in Suffolk, UK, was selected for a demonstration MAR scheme, with the goal of supplying additional summer irrigation water. The recharge source was a 4.6 km drainage channel that discharges to the River Deben estuary. Trialling the scheme in June 2022, 12,262 m3 of source water were recharged to the aquifer over 12 days via a lagoon and an array of 565 m of buried slotted pipes. Groundwater levels were raised by 0.3 m at the centre of the recharge mound with an approximate radius of 250 m, with no detrimental impact on local water features observed. The source water quality remained stable during the trial with a mean chloride concentration (133 mg L−1) below the regulatory requirement (165 mg L−1). The fraction of recharge water mixing with the groundwater ranged from 69% close to the centre and 5% at the boundary of the recharge mound, leading to a reduction in nitrate-N concentration of 23.6 mg L−1 at the centre of the mound. During July–September 2022, 12,301 m3 of recharge water were abstracted from two, 18 m boreholes to supplement surface irrigation reservoirs during drought conditions. However, the hydraulic conductivity of the Crag aquifer (∼10 m day−1) restricted the yield and thereby reduced the economic viability of the scheme. Construction costs for the MAR system were comparatively low but the high costs of data collection and securing regulatory permits brought the overall capital costs to within 18% of an equivalent surface storage reservoir, demonstrating that market-based mechanisms and more streamlined regulatory processes are required to incentivise similar MAR schemes.

Investigating the role for adaptation of the microbial community to transform trace organic chemicals during managed aquifer recharge

Effect of Long-Term Application of Chemical Fertilizers on Microbial Biomass and Functional Diversity of a Black Soil

The design, operation, and evaluation of managed aquifer recharge (MAR) and other anthropogenic aquifer recharge (AAR) systems should be based on a sound understanding of hydrogeological principles, local hydrogeological conditions, and how hydrogeology impacts system performance. A review of the historical performance of MAR systems revealed that system performance is dependent on local hydrogeological conditions and that there may not be an engineered solution to compensate for adverse local hydrogeological conditions. Hydrogeology basics most applicable to AAR are reviewed.

Rising trends in global population have resulted in increased urbanization, industrialization, and food demands. This has resulted in the rapidly increasing water demands for domestic, agricultural and industrial sectors; which have severely depleted groundwater resources in Pakistan. The urban centres like Lahore city—the capital of Punjab province and the 2nd largest city of Pakistan. To address this challenge, a field-scale Managed Aquifer Recharge (MAR) system integrated with Rainwater Harvesting (RWH) was developed and tested to evaluate its feasibility and efficiency for urban groundwater recovery. In this system, rainwater collected from paved surfaces was filtered and injected into a Pleistocene sand aquifer through recharge wells. Double filtration mechanism has been introduced in the model to ensure good quality rainwater is recharged into the aquifer. Field monitoring during multiple rainfall events demonstrated successful infiltration and aquifer-storage, with recharge volumes of 150,700, 281,097, and 89,887 L of rainwater corresponding to potential domestic water supplies for 132, 246, and 79 days for an average household respectively. The results confirm that decentralized RWH–MAR systems can significantly enhance aquifer replenishment in overexploited urban aquifers. The study underscores the viability of such systems for broader implementation in Punjab and other similar semi-arid regions, contributing to sustainable groundwater management and urban water resilience in Pakistan.

Soil development and microbial functional diversity: Proposal for a methodological approach