An integrated geospatial and analytical hierarchy process approach for sustainable water management in the Amravati District, India

Groundwater serves as a critical source of fresh water, supporting a myriad of applications including domestic consumption, agriculture, and industry. In India, a country that is the world's largest consumer of groundwater, it is particularly vital, with 230 km³ being extracted annually, which constitutes over a quarter of the global total (World Bank Report). A staggering 60% of irrigated agriculture and 85% of drinking water supplies in India rely on groundwater (Kolanuvada et al. 2019). However, accessibility and availability of groundwater exhibit considerable variation across regions owing to diverse geological, hydrological, and environmental factors (Bourjila et al. 2021).

Despite the crucial role of groundwater, India faces significant challenges in its management. According to a report by NITI Aayog (2018), about 0.6 million people in India face high to extremely high water stress due to mismanagement and scarcity of fresh water, and approximately three-fourths of the households lack access to drinking water within their premises (https://social.niti.gov.in/uploads/sample/water_index_report.pdf). Over-extraction has led to aquifer-stress syndromes such as declining groundwater levels and degradation of water quality (Patra et al. 2018). Furthermore, water scarcity poses severe threats to the sustainability of agriculture, long-term food security, livelihoods, and economic growth in the country, with more than a quarter of the harvest estimated to be at risk. These issues are particularly pronounced in tropical and subtropical regions with high population densities and rapid economic development. For sustainable utilization and management of groundwater resources, it is imperative to assess potential zones and identify areas that can sustainably meet water demands. Traditional groundwater exploration methods, which rely on hydrogeological, drilling, geological, and geophysical strategies, are often time-consuming, expensive, and sometimes inadequate as they may not consider the factors influencing groundwater movement and occurrence (Jha et al. 2010; Oh et al. 2011).

Several studies have contributed to the understanding of groundwater dynamics in the Amravati district, Maharashtra, laying the groundwork for the current research. A notable investigation by Sharma et al. (2022) focused on the hydrogeological aspects and groundwater quality in the region, providing crucial insights into the aquifer characteristics and potential challenges related to water quality. In addition, the work of Nair & Mirajkar (2021) examined the impact of land use changes on groundwater recharge, shedding light on the anthropogenic factors influencing the district's hydrological balance. In addition, a good amount of work has been carried out by different workers on different tehsils, watersheds, and individual villages of the district for by Khadri (2009) and Varade et al. (2017). These prior investigations collectively contribute to the foundation of knowledge upon which the current paper is based on, illustrating the evolving understanding of groundwater dynamics in this critical region.

Groundwater potential zonation (GWPZ) provides essential information for water resource managers and policymakers to make informed decisions regarding groundwater development, allocation, and conservation. This process aids in identifying optimal locations for well drilling, managing water supply and demand, and optimizing groundwater extraction. Moreover, understanding groundwater potential zones is essential for the sustainable utilization of this finite resource. Climate change poses additional challenges to water availability and distribution; mapping groundwater potential zones can facilitate adaptation to changing hydrological conditions, identify areas resilient to climate variability, and assist in developing strategies to mitigate water scarcity risks (Ahmad et al. 2020; Upadhyay et al. 2023).

Recently, remote sensing and Geographic Information Systems (GIS) have been integrated to evaluate groundwater potential zones with promising results (Sener et al. 2005; Ghosh et al. 2016; Golla 2020). Analytical hierarchy process (AHP) through GIS, in particular, has proven to be efficient for spatial data management (Shekhar & Pandey 2015). Many researchers have utilized AHP to assign weights to various thematic layers for identifying groundwater potential zones. Moreover, multi-criteria decision-making (MCDM) analysis has emerged as a valuable tool for water management, adding structure, auditability, precision, and consistency to decisions (Jha et al. 2010; Arulbalaji et al. 2019).

MCDM techniques, particularly the AHP, have proven to be powerful tools in the realm of GWPZ. Groundwater, being a critical water resource, requires systematic assessment and management, and MCDM methods provide a structured approach to decision-making by considering multiple criteria simultaneously. AHP, specifically designed for dealing with complex decision problems, involves breaking down a problem into a hierarchical structure and making pairwise comparisons to derive relative importance weights for criteria and alternatives. In the context of GWPZ, the AHP method offers a comprehensive framework for incorporating various hydrogeological, environmental, and socio-economic factors that influence groundwater occurrence and availability (Pande et al. 2021).

One of the primary strengths of AHP is its ability to handle diverse and often conflicting criteria. In GWPZ, factors such as geological formations, land use, soil characteristics, slope, and proximity to surface water bodies can significantly impact groundwater availability. AHP allows researchers and decision-makers to assign weights to each criterion based on their relative importance, providing a quantitative basis for integrating diverse data types. This weighted integration helps in creating a more holistic and accurate GWPZ map. The hierarchical structure of AHP is well-suited for groundwater assessments. At the top level, overarching goals, such as identifying suitable zones for groundwater extraction, guide the decision-making process. Sub-levels break down these goals into specific criteria, such as aquifer properties, recharge potential, and land use. Pairwise comparisons at each level enable experts to systematically evaluate the significance of each criterion concerning others, resulting in a set of relative weights (Machiwal et al. 2011; Kaliraj et al. 2014; Shekhar & Pandey 2015).

Therefore, challenges faced by India in groundwater management, including high water stress, scarcity, and over-extraction, lead to declining levels and degraded water quality. This emphasizes the importance of sustainable groundwater utilization and introduces the limitations of traditional groundwater exploration methods. Previous studies in the Amravati district, Maharashtra, show the hydrogeological aspects and anthropogenic factors affecting groundwater dynamics. The integration of remote sensing, GIS, and AHP for GWPZ is important, citing the efficiency of AHP in handling diverse criteria. Building upon these advancements, this study aims to delineate, identify, and map the groundwater potential zones in the Amravati district, Maharashtra, India, employing the GIS-based MCDM AHP method. By utilizing meteorological, hydrological, and hydrogeological characteristics, this study seeks to contribute to sustainable water resource development and planning in the area.

The climate of the Amravati district is classified as a hot semi-arid climate, influenced by its location in the central part of Maharashtra. The district experiences distinct seasons with temperature, rainfall, and humidity variations throughout the year. The breakdown of the different seasons and their characteristics are as follows: Amravati district receives moderate to heavy rain from June to September, which helps replenish water resources and support agricultural activities. The southwest monsoon season lasts from June to September for the monsoon season. The minimum and maximum temperatures are 15.1 and 42.2 °C, respectively. The area has three primary rivers: Tapi, Purna, and Wardha. The Purna River originates from the southern slopes of the Gavilgarh Hills and initially flows in a southeasterly direction. It then turns westward and forms a part of the district boundary between Amravati and Akola. Notable tributaries of the Purna include Pedhi, Arna, Chandrabhaga, and Shahnur. The Wardha River, on the other hand, originates at Multai in Madhya Pradesh and forms the eastern boundary of the district. It receives several short tributaries on its right within the Maru and Chargat districts. Maru and Chargat are important tributaries that join the Wardha. Finally, the Tapi River flows along the northwest boundary of the district. Its tributaries include Khardu, Sipna, Dewal, and Dhulghat. In terms of drainage patterns, the central area exhibits a dendritic pattern. However, Purna River's alluvium basin displays a parallel to sub-parallel drainage pattern and is characterized by almost flat terrain. The northern part of the district predominantly comprises a hilly terrain and is densely covered by forests. Specifically, the northwestern part is characterized by thick forests of Sagwan trees. Moving toward the central part of the district, it is covered by the Purna alluvium, which spans a total area of 3,053 km². The slope in the north–south direction is approximately 9 m deep, extending to a depth of 15 km. Similarly, the east–west slope measures 15 m deep, reaching a depth of 15 km.

The Purna alluvium is composed of silt, clay, and sand. In addition, the foothill region of the Satpura range, known as the Bajada zone, covers parts of Anjangaon Surji, Achalpur, and Chandur Bazar talukas. Clay, boulders, and pebbles characterize this area. The total coverage of this specific region accounts for 25% of the total district's area, while the remaining 75% consists of the Deccan Traps, primarily composed of jointed, vesicular basalt. In summary, the northern part of the district is predominantly hilly and forested, with the northwestern section containing dense Sagwan forests. The central part of the district is covered by the Purna alluvium, consisting of silt, clay, and sand. In addition, the Bajada zone in the foothills of the Satpura range encompasses parts of three talukas characterized by clay, boulders, and pebbles. The remaining three-fourths of the district is primarily composed of jointed, vesicular basalt of the Deccan Trap formation.

Data on geological, topographical, and hydrological factors such as lithology, geomorphology, land use/land cover (LULC), drainage density, lineament density, rainfall, soil type, elevation, and slope were collected. Satellite imagery and digital elevation models for the study area were acquired. The source and spatial and temporal resolutions of data are mentioned in Table 1. The criteria affecting the groundwater potential, such as geology, slope, LULC, rainfall, soil type, and proximity to surface water bodies, were identified. Weights were assigned to each criteria based on their relative importance in groundwater occurrence. The data for each criterion were normalized to a common scale, typically ranging from 0 to 1, ensuring comparability across different criteria.

The AHP serves as a tool for making decisions based on multiple criteria. Employing an eigenvalue approach for pairwise comparisons, it offers a methodology to standardize the numeric scale, accommodating measurements of both quantitative and qualitative performances. This scale spans from 1/9 denoting ‘least valued than’ to 1 representing ‘equal’ and up to 9 indicating ‘absolutely more important than’, encompassing the entire range of the comparison spectrum (Vaidya & Kumar 2006; Ghezelayagh et al. 2020). A pairwise comparison matrix was developed to assess the relative importance of each criterion using the AHP method. Composite weights for each location were calculated by multiplying the normalized values of each criterion by their corresponding weights and summing these weighted values. Sensitivity analysis was performed to assess the influence of criteria weights on the final groundwater potential mapping results. The weights of criteria were modified to observe changes in the potential zones, ensuring the robustness of the mapping process. Standardized data layers of influencing factors were overlaid using GIS software. Weights were assigned to each influencing factor based on their relative importance. Composite MIF values for each location were obtained by multiplying the normalized values of each factor by their corresponding weights and summing these weighted values.

Composite weights from the AHP method were combined with composite MIF values. The combined values were classified into different potential zones, such as high-potential, moderate-potential, and low-potential zones. A GWPZ map was generated using GIS techniques. The GWPZ map was validated using independent groundwater data such as borehole yields or water table measurements. The accuracy of the map was assessed using appropriate statistical measures and error matrices. The results of the GWPZ map were interpreted, highlighting areas with high potential for groundwater availability. A comprehensive analysis report in the form of this manuscript was prepared, documenting the methodology, data sources, results, and recommendations for groundwater management and development in the study area.

The MIF, a commonly employed MCDM technique in environmental management, proves to be valuable in delineating groundwater potential zones. This involves assigning suitable weights to different factors and feature classes, determined by their impact on groundwater flow and storage (Zghibi et al. 2020).

The groundwater potential zone mapping process yielded significant findings that provide valuable insights into the distribution of groundwater potential in the Amravati district of Maharashtra, India. By integrating various influencing factors, including lithology, geomorphology, soil, land use, slope, drainage density, and rainfall, the study effectively identified distinct groundwater potential zones across the region. The AHP was employed to determine the relative weights of these factors, while the MIF technique facilitated the integration and synthesis of the influencing factors. The analysis of the influencing factors revealed their varying degrees of significance in determining the groundwater potential. For instance, lithology emerged as a critical factor, with certain rock types exhibiting higher groundwater potential due to their permeability and aquifer characteristics. Geomorphological features, such as flood plains and alluvial plains, were also found to have a considerable influence on groundwater availability. Moreover, land use patterns, particularly in areas with high agricultural activity, demonstrated a positive correlation with groundwater potential, as these regions often exhibited enhanced infiltration and recharge capabilities. The integration of the influencing factors using the MIF technique enabled the creation of distinct groundwater potential zones throughout the study area. The resulting maps depicted zones ranging from very high potential to very low potential. Notably, the northeastern and northwestern regions of the Amravati district exhibited the highest groundwater potential, primarily attributed to favorable lithology, gentle slopes, and high infiltration capacities. These findings have significant implications for groundwater resource management in the Amravati district.

The identification of high-potential zones can guide the sustainable allocation of groundwater resources for various purposes, such as irrigation and domestic water supply. In addition, the delineation of lower potential zones highlights areas where groundwater extraction should be carefully managed to prevent depletion and ensure long-term resource sustainability. In the following section, the details of all the factors that influence the groundwater potential is discussed.

The LULC factor significantly influences groundwater recharge, as highlighted by various studies (Shaban et al. 2006; Kaliraj et al. 2014; Ghosh et al. 2016). Accurate and reliable information regarding current and future LULC is essential for effective resource management (Choudhury et al. 2023; Rani et al. 2023; Ahmad et al. 2023). This information encompasses soil deposits, residential area distribution, and vegetation cover (Table 2).

Geology plays a crucial role in groundwater potential mapping, as it provides valuable information about the subsurface characteristics and geological formations that influence the occurrence, movement, and availability of groundwater. Understanding the geological context is essential for effective groundwater resource management and sustainable water supply. In summary, geology provides the foundation for groundwater potential mapping by offering insights into the subsurface characteristics that influence the occurrence and movement of groundwater. This information is vital for sustainable water resource management and planning, especially in regions where groundwater is a significant source of freshwater supply.

The analysis resulted in the classification of the study area into five distinct groundwater potential zones: (i) poor, (ii) fair, (iii) moderate, (iv) good, and (v) excellent. The groundwater potential map in Figure 11 notably reveals that the northwestern regions of the district exhibit excellent groundwater potential.

Poor groundwater potential zone: Encompassing 9% of the study area, the regions within this category, predominantly in the Teosa tehsil, are characterized by scarce groundwater availability. Given the importance of water for various purposes, it is imperative to explore alternative water sources, alongside implementing water conservation strategies such as rainwater harvesting, especially in these zones.

Fair groundwater potential zone: Approximately 37% of the district, including areas like Warud, Morshi, Amravati, Dhamangaon Railway, Nandgaon Khandeshwar, and Chandur Railway, falls under this category. While these zones possess a somewhat better groundwater potential compared to the poor zones, judicious water use is essential. Implementing conservation strategies and monitoring extraction rates are advisable to sustain the water supply.

Moderate groundwater potential zone: Constituting 28% of the study area, the regions in this category exhibit moderate groundwater availability. Notably, the central part of the district including areas like Chandur Bazar, Achalpur, Anjangaon Surji, and parts of Daryapur and Bhatkuli fall in this category. Despite the relatively favorable conditions, monitoring and management practices are crucial to prevent the imbalance between water demand and supply.

Good groundwater potential zone: This category, covering 13% of the area, is characterized by higher groundwater availability. Sustainable exploitation and management are essential to maintain the resource quality. Adopting efficient irrigation methods, promoting recharge measures, and formulating water management strategies are critical for the long-term preservation of groundwater in these zones.

Excellent groundwater potential zone: Also occupying 13% of the district, the zones under this category, mainly Dharni and Chikhaldara Tehsil, have exceptionally high groundwater potential. While these regions can meet substantial water demands, it remains essential to manage the resource sustainably to avoid future depletion. The systematic assessment of groundwater potential zones in the Amravati District elucidates the spatial variability in groundwater availability. The study unveils that while some regions have abundant groundwater resources, others face limitations. The results highlight the necessity for tailored water management strategies across different zones. Conservation practices, sustainable utilization, and exploration of alternative water sources are essential components for comprehensive water resource management in the district (Table 3).

To ascertain the validity and reliability of the groundwater potential zones derived from this study, the results were compared with existing groundwater data for the Amravati district. The objective was not only to gauge the accuracy of the generated zones but also to discern how closely these zones align with the actual groundwater conditions in the region.

The benchmark data comprised records of groundwater levels, well yields, and aquifer properties, extracted from local monitoring wells and previous hydrogeological studies in the area. These sources served as an essential backdrop against which the efficacy of the groundwater potential zones, ascertained through the integration of the AHP and MIF techniques, could be evaluated.

The juxtaposition of the derived groundwater potential zones with the existing data revealed a noteworthy concordance. In the zones earmarked as having high groundwater potential, the extant data consistently showed elevated groundwater levels and sustainable well yields. In contrast, the areas delineated as low-potential zones were in agreement with regions that had limited groundwater reserves and diminished well yields.

In addition, the analysis uncovered areas where the derived groundwater potential zones offered novel insights that were not evident from the extant data. Specifically, the study highlighted previously unrecognized zones with significant groundwater potential. These zones are invaluable as they present new opportunities for groundwater exploration and development, which can substantially bolster future water resource management and planning efforts in the region.

The strong agreement between the derived groundwater potential zones and the existing data substantiates the reliability of the methodologies employed in this study. Moreover, the identification of new potential zones is pivotal, as it widens the horizon for informed decision-making in groundwater management. Consequently, this comparison not only validates the groundwater potential zones established through this study but also underlines their significance in augmenting the body of knowledge pertinent to groundwater availability in the Amravati district.

Two MCDM methods, namely, the AHP and MIF, were applied using a geospatial analysis framework to delineate GWPZ in the Amravati District. The factors that were considered include lithology, elevation, LULC, slope, geomorphology, lineament density, rainfall, drainage density, rainfall, and soil type. The Amravati district is a part of the Vidarbha region, which is often considered as a drought-prone region where groundwater is an essential source for agricultural irrigation and water supply through dug wells and borewells. The final groundwater prospect map was classified into five categories: poor, fair, moderate, good, and excellent. According to the results, 13% of the total study area exhibits excellent to good groundwater prospects, 28% falls under the moderate category, 37% is in the fair zone, and the remaining 8% showcases poor prospects. The results of this study are imperative given the increasing demand for fresh water and the challenges associated with the geographical structure of the Amravati district, which experiences inadequate water resources due to the outflow of surface and groundwater and overexploitation. The integrated approach, combining geospatial technologies such as remote sensing and GIS with the AHP method, demonstrated its efficacy in identifying and mapping groundwater potential zones in the geographically challenging terrain of the Amravati district. This information holds practical significance for the formulation of targeted groundwater exploration and sustainable management plans, especially considering the district's heavy reliance on groundwater for agriculture. The findings are instrumental in guiding policymakers and water resource managers in identifying priority areas for the implementation of water conservation projects and programs. By offering a comprehensive understanding of the spatial distribution of groundwater potential, the integrated map aids in targeted resource allocation for groundwater management. It is essential to utilize this information to focus on areas with higher groundwater potential, especially during peak summer months when shallow aquifers are at the risk of drying up. While this study provides valuable insights into the groundwater potential zones in the Amravati district, it is recommended that future studies incorporate real-time monitoring data and consider climate change projections to enhance the robustness of the groundwater potential assessment. In addition, further research on community engagement and capacity building for sustainable groundwater management practices could complement the technical insights gained from this study.

Data cannot be made publicly available; readers should contact the corresponding author for details.

The authors declare there is no conflict.