The rising water crisis requires effective and innovative techniques to safeguard the dwindling groundwater resources. Managed Aquifer Recharge (MAR) is a groundwater management approach to minimize groundwater depletion and ensure water security across a range of climatic regions. It is implemented globally to maximize aquifer storage, reduce saltwater intrusion, prevent land subsidence, reduce flooding hazards, and enhance agricultural production, while ensuring better water quality and quantity. This review followed the PRISMA 2020 guidelines to systematically select relevant publications from scientific databases between 1980 and 2023. Systematic review and bibliometric synthesis indicate that river water (surface water runoff to streams and rivers), stormwater, and reclaimed wastewater were the main water sources for MAR. Tracers, water balance, and numerical modeling methods were commonly used approaches for evaluating MAR systems. Global studies on MAR reveal a significant relationship with the aridity index, indicating that highly arid areas experience negligible recharge due to the limited availability of excess water for recharge. These regions are prone to groundwater depletion but hold potential for MAR using sources such as treated wastewater, stormwater, and desalinated water. MAR projects have been established worldwide for agricultural and domestic needs at different regional scales. MAR not only increases groundwater storage but also has global benefits, including water security, environmental enhancement, economic benefits, technological advancement, climate change mitigation, and community engagement. The challenges of MAR include financial, technical, and hydrogeological issues, social acceptance, ecological concerns, and climate change. Our systematic analysis highlights the advantages of MAR in addressing the pressing issue of water scarcity for agriculture and domestic use. This underscores the importance of an integrated, well-informed, and region-specific strategy and policies to fully harness MAR's capabilities in guiding the world toward a sustainable future.

malls in the world , currently ranked 12th for number of skyscrapers . “Jakarta is the go-to city for all things,” says Hendricus Andy Simarmata, a lecturer at the Urban Planning Department at the University of Indonesia. “It’s the center of administration, the center of the economy, culture, and entertainment. Over the years Jakarta has grown uncontrollably into a megacity with no environmental support system.” Ultimately that’s why it is sinking today. ( See how villagers in Java live with their sinking coast. )   Fishermen carry fish in crates in the port of Muara Angke, in North Jakarta, one of the most rapidly subsiding and frequently flooded parts of the city. Fishers here worry that the government's planned coastal protection measures will limit their access to the open sea, the source of their livelihood. The Waladuna Mosque in Muara Baru in North Jakarta has been affected by coastal floods since 2000 and is now no longer used. Jakarta needs water In 2007, after the catastrophic flood, the provincial government adopted a regulation requiring at least 30 percent of the city’s total area to be allocated to green, open space. More green space is not just a matter of general well-being. It’s also needed to absorb floods driven by torrential rains—and to funnel them into recharging the city’s depleted groundwater aquifers. Less than 10 percent of the city is green today. Massive groundwater extraction is one of the main drivers of land subsidence in Jakarta, a sprawling concrete labyrinth that’s not supported by a reliable water supply network. Jakarta’s piped-water system serves fewer than one million households, a little over a quarter of the city’s total . The rest rely primarily on pumping groundwater. While such pumping is not illegal, it is subject to taxation. But the provincial government is unable to monitor and tax the untold numbers of unregulated deep wells scattered across the city, mostly hidden behind closed doors. Batubara, who has spent years re In 2002, the government built the coastal wall, to give the residents peace of mind and time—a respite from the steady sinking of the land under the city and the steady rising of the sea. But just five years later, in 2007, the wall proved no match for the worst floods in Jakarta’s modern history. Driven by a storm coming off the Java Sea and torrential rains, the floods claimed 80 lives around the city and caused hundreds of millions of dollars of damage . In Muara Baru, the storm surge collapsed the wall, and the sea flooded Suhemi’s house. “The water reached more than one meter,” she recalls. “My father almost died after being swept by the current. Residents of Pesanggrahan in West Jakarta wait out the 2020 flood on their second floor. The flood caused an estimated $70 million in damages. But as the government leaves the sinking capital , what is to become of the 10 million people like Suhemi who still live there? The coastal wall is being extended, and there are grand plans for a giant artificial island in Jakarta Bay—but the funding for these schemes remains uncertain. And the fundamental cause of the sinking—the lack of an adequate public water supply, which has led to massive over-extraction of groundwater—remains mostly unaddressed. The 2007 flood destroyed Suhemi’s home and small restaurant, her family’s sole means of support. “We’ve made drainage so that the water will not inundate the road, but still it’s always wet.” A problem with deep roots At Cilincing, a fishing village in North Jakarta, the Rawa Malang River flows into Jakarta Bay; the city center lies on the horizon, about 10 miles to the southwest. This area floods constantly during the rainy season, but the government is building a wall along the coast to hold back storm tides. The Waladuna Mosque in Muara Baru in North Jakarta has been affected by coastal floods since 2000 and is now no longer used. Jakarta needs water In 2007, after the catastrophic flood, the provincial government adopted a regulation requiring at least 30 percent of the city’s total area to be allocated to green, open space. More green space is not just a matter of general well-being. It’s also needed to absorb floods driven by torrential rains—and to funnel them into recharging the city’s depleted groundwater aquifers. Less than 10 percent of the city is green today. Massive groundwater extraction is one of the main drivers of land subsidence in Jakarta, a sprawling concrete labyrinth that’s not supported by a reliable water supply network. Jakarta’s piped-water system serves fewer than one million households, a little over a quarter of the city’s total . The rest rely primarily on pumping groundwater. While such pumping is not illegal, it is subject to taxation. But the provincial government is unable to monitor and tax the untold numbers of unregulated deep wells scattered across the city, mostly hidden behind closed doors. In coastal areas like North Jakarta, where there is no piped water readily available today, residents drill wells as deep as 150 meters, or around 500 feet. “If you drill less than 50 meters, all you get is saline water,” says Arti Astati, the community leader in the neighborhood of Muara Angke. One deep well can serve 50 households. The alternative is to buy water in 40-liter jerrycans, which are sold from pushcarts by distributors who pump it from wells elsewhere in Jakarta. A typical family of four making less than $7 per day could easily spend a fifth of that on water, Astati says. “All we want is to not be concerned about flooding anymore.” Related Topics CLIMATE CHANGE GROUNDWATER WATER RESOURCES POPULATION URBAN PLANNING CITIES You May Also Like ENVIRONMENT A river crisis is unfolding in the American West ENVIRONMENT Why Europe wants to tear down thousands of its dams ENVIRONMENT Desert threats and why they matter ENVIRONMENT Mexico City is running out of water—are these cities next? ENVIRONMENT What happens when a country loses most of its lakes?