The State-of-the-Art Estimation of Groundwater Recharge and Water Balance with a Special Emphasis on India: A Critical Review

Groundwater recharge estimation is essential for sustainable water management and water supply schemes. In this paper, we review groundwater recharge estimation techniques and identify the appropriate methods by considering India’s hydrological and climatic conditions. Significant components of recharge, factors affecting groundwater recharge, aquifer systems of India, and historical groundwater recharge estimation practices are reviewed. Currently used recharge estimation methods are assessed based on case studies. The most popular estimation methods are studied and compared based on their application in various regions. It is observed that the accuracy of the recharge estimates is largely influenced by false assumptions, the possibility of erroneous measurements, a potential lack of reliable data, and a variety of problems associated with parameter estimation. The suitability of different methods for a region is found to depend on time and space considerations, the objective of the study, hydrogeological condition, and availability of data. In Indian conditions, it is suggested to use water table fluctuation and water balance methods for the recharge estimation, provided that accurate water level measurements are assured.

Smart Technologies for Sustainable Water Management: An Urban Analysis

As projections highlight that half of the global population will be living in regions facing severe water scarcity by 2050, sustainable water management policies and practices are more imperative than ever. Following the Sustainable Development Goals for equitable water access and prudent use of natural resources, emerging digital technologies may foster efficient monitoring, control, optimization, and forecasting of freshwater consumption and pollution. Indicatively, the use of sensors, Internet of Things, machine learning, and big data analytics has been catalyzing smart water management. With two-thirds of the global population to be living in urban areas by 2050, this research focuses on the impact of digitization on sustainable urban water management. More specifically, existing scientific literature studies were explored for providing meaningful insights on smart water technologies implemented in urban contexts, emphasizing supply and distribution networks. The review analysis outcomes were classified according to three main pillars identified: (i) level of analysis (i.e., municipal or residential/industrial); (ii) technology used (e.g., sensors, algorithms); and (iii) research scope/focus (e.g., monitoring, optimization), with the use of a systematic approach. Overall, this study is expected to act as a methodological tool and guiding map of the most pertinent state-of-the-art research efforts to integrate digitalization in the field of water stewardship and improve urban sustainability.

Sustainable Water Flows in Era of Climate Change

The flow of water in rivers is of paramount importance to maintain supply of food and energy requirements to a great extent. The minimum flow in perennial rivers is subjected to groundwater availability, it is further replenished by the water added through precipitation. Climate change not only increases the melting of glaciers and sea level rise, but also influences the surface water flow and quality. As agriculture is directly affected by changing precipitation pattern, the reduction in water resources and untimely addition of water, both act havoc to the food production process. This interconnection makes agriculture even more vulnerable to the scenarios of global warming and climate change. Studies on food-energy-water nexus has opened new avenues of research in sustainable water management. The role of sustainable flow of water in rivers is highlighted which needs to be understood in era of climate change.

Factors Influencing the Awareness and Adoption of Borehole-Garden Permaculture in Malawi: Lessons for the Promotion of Sustainable Practices

Using wastewater accumulating around rural waterpoints to irrigate community gardens, borehole-garden permaculture (BGP) presents a method of sustainable water management. BGP also presents public health benefits through the removal of stagnant water around boreholes, key Malaria breeding grounds, and through providing year-round food to supplement diets. By analysing a dataset of over 100,000 cases, this research examines the awareness and adoption of BGP across Malawi. Generalised linear models identified significant variables influencing BGP awareness and uptake revealing that socioeconomic, biophysical and waterpoint-specific variables influenced both the awareness and adoption of BGP. BGP had low uptake in Malawi with only 2.4% of communities surveyed practising BGP while 43.0% of communities were aware of BGP. Communities in areas with unreliable rainfall and high malaria susceptibility had low BGP awareness despite BGP being particularly beneficial to these communities. This work suggests that future work in the promotion of BGP should focus their efforts within these areas. Furthermore, this work highlights the value of community networks in knowledge sharing and suggests that such social capital could be further used by NGOs and the Government of Malawi in the promotion of BGP and other sustainable practices.

Examination of Sustainable Water Management at Norway’s Major Hub Airport: The Case of Oslo Airport Gardermoen

The present study used a detailed qualitative longitudinal research approach to examine the trends of water consumption, wastewater volumes, and drainage water volumes in Oslo Airport Gardermoen, which is Norway’s major hub airport, between the years 2005 and 2020. An overall upward trend was observed in the water consumption at Oslo Airport Gardermoen, which was consistent with the growth in air traffic and aircraft movements during the study period. The annual water consumption per enplaned passenger was observed to fluctuate during the study period. While the lowest water consumption per passenger (8 liters per passenger) was recorded in 2008, the highest levels (14.6 liters per passenger) were recorded in 2020. The annual water consumption (cubic meter per aircraft movement) increased during the study period, which was consistent with the growth in aircraft movements and the use of larger aircraft. The annual wastewater volume generally increased during the study period, while the annual drainage water volume fluctuated remarkably during the study period, with the latter reflecting varying drainage patterns at the airport. Oslo Airport Gardermoen has implemented a range of sustainable water management practices to supplement its existing water management practices and policies.

Adoption of Sustainable Water Management Practices among Farmers in Saudi Arabia

Promoting sustainable water management (SWM) practices among farmers is essential in order to ensure water sustainability. This study aimed to analyze patterns in the adoption of SWM practices by farmers at the farm level, and how their awareness regarding the causes of agricultural water pollution influence SWM adoption. Face-to-face interviews were conducted to collect field data using structured questionnaires from 129 farmers in the Riyadh region, Saudi Arabia. The results indicate that 38.8% of farmers had a high awareness of the causes of water pollution from agriculture. Approximately half of the farmers exhibited a high rate of adoption of SWM practices, most of whom adopted water quality and soil management practices. The findings reveal a positive association (0.37, p < 0.01) between SWM adoption and awareness regarding water pollution caused by agriculture, whereby the farmers with more awareness regarding the causes of water pollution from agriculture showed a higher level of adoption for 55% of the SWM practices. Multiple regression analysis revealed that the awareness levels regarding the causes of agricultural water pollution and cultivated crops significantly influenced the adoption of SWM by farmers. The findings and implications provide an understanding of the SWM practices of farmers, and offers insights for policymakers aiming to reformulate strategies and policies combatting water scarcity in Saudi Arabia.