Water resources are being subjected to unprecedented pressure due to population growth, urbanization,

industries, intensive farming and the increasing effects of global warming. These stressors are compromising the

quality and quantity of freshwater resources, escalating threats to human health, life forms, and to socio-

economic conditions. Traditional methods that consider hydrology, water quality, treatment technologies, and

resilience planning as stand-alone areas are increasingly less sufficient, since the development of one area is

often reliant on the development of the others. The present review synthesizes the recent studies that were

published within 2014-2025 in four interconnected pillars, namely: hydrological modelling and climate effects

study, water quality and transport of contaminants, water and wastewater treatment innovations, and integrated

management through resilience. The usefulness of integrated approaches is demonstrated in case studies

conducted in different areas such as Singapore, the Netherlands, California, and Africa, among others. The

Water is fundamental to survival, ecological well-being, and economic growth of human beings (Kumar et al.,

2023). However, in the twenty-first century, water resources all over the world have never been as much

challenged. Over the last few decades, the swift population increase, urbanization, industrialization, and

intensive agriculture have led to the rise of water demand and has also diminished water quality due to pollution

and excessive use (Gude, 2015; Wang et al., 2024). Climate change also magnifies these problems by changing

the precipitation patterns, rising the number of severe weather events, and the severity of droughts and floods

(Brown et al., 2015; Gupta et al., 2024). All these stressors endanger the sustainability of freshwater resources

and cause severe threats to the health of the population, food security, and ecological integrity (Islam et al., 2025;

O’Donnell et al., 2024).

The solution to such complicated issues lies in the fact that the current approach to these issues is fragmented

challenges (Sharvelle, 2022; Snow et al., 2023). The review relies on the literature published 2014-2025 in order

to define the new trends, recent innovations, unresolved gaps, and the prospects of future interdisciplinary

research (Dai, 2020; McKay, 2024). By doing that, it aims to educate scholars, policymakers, and practitioners

on the avenues of creating sustainable water systems that are adaptive and resilient (Mostafavi et al., 2023;

Edwards, 2024).

The conceptual basis of this review consists in the acknowledgment that water systems are all interconnected

and hydrology, water quality, treatment technologies, and resilience strategies are functioning components and

not separate domains. These areas have frequently been tackled in isolation in traditional approaches thereby

limiting effectiveness of interventions and resulting in disjointed results. In comparison, integrated framework

(Sivapalan et al., 2025; Kumar et al., 2023). In contrast with other methods that address them individually,

integration highlights the fact that natural processes and artificial systems are interrelated and should be

controlled as one (Gupta et al., 2024; McKay, 2024).

Historically, the discipline of water studies developed in silos. Hydrologists studied the dynamics of

precipitation-runoff and aquifer storage as well as surface water flow, but with minimal or no connection to

treatment or adaptation requirements (Zeng et al., 2023; McIntosh et al., 2023). Treatment engineers did not

consider hydrological variability and resilience in their designs and were working on such systems mostly to

remove contaminants (Gude, 2015; Dai, 2020). The policymakers placed too little attention on hydrological and

technological evidence by focusing on climate adaptation frameworks (Hagen, 2022; Edwards, 2024).

The water system is disregarded as an integrated system where hydrological processes, pollutant transport,

treatment technologies, and resilience strategies interact with each other in an integrated perspective (Nelson et

al., 2023; Ma, 2022). The next line of action is hydrology, which defines the availability and quality of water

and treatment systems as engineered interventions, which preserve water resources and reclaim value (Snow et

al., 2023; Bradley et al., 2024). These components are overlapped by the resilience strategies to make sure that

the water system can survive and adjust to the extremes in the climate, floods, droughts, and even the event of

contamination (Mostafavi et al., 2023; Sivapalan et al., 2025).

coordinated progress across hydrology, treatment, and policy dimensions (Wang et al., 2024; Chu, 2022).

Over the past few decades, mathematical science has made numerous advances in hydrology, especially in the

use of computational modeling, big data analytics, and satellite data. Physical models like SWAT, VIC, and

MODFLOW continue to be a basis of watershed hydrology and groundwater flow simulation, but are commonly

limited by parameter uncertainty and a lack of data (Brown et al., 2015; McIntosh et al., 2023). Recently, it has

been advanced with the incorporation of machine learning algorithms like long short-term memory (LSTM)

networks, which enhance prediction of rainfall-runoff and streamflow in different climatic conditions (Islam et

al., 2025; Nelson et al., 2023).

hydrology data allowing to track almost real-time on a regional and even continental level (Andreadis & Clark,

2023; Zeng et al., 2023). The innovations have also enhanced water balance simulation, as well as aiding early

flood and drought prediction systems.

Climate change has a major impact on the processes of the global hydrological cycle: it increases the severity of

precipitation events and alters the evapotranspiration patterns and snowmelt regimes (O’Donnell et al., 2024;

Hagen, 2022). Increased floods and extended droughts are being recorded in many areas, weakening reliability

in water supply and ecosystem stability (Behrangi et al., 2020; Segura et al., 2020). The future risks are now

shown in detail in coupled climate-hydrology models under CMIP5 and CMIP6 scenarios, showing vulnerability

of semi-arid basins, coastal deltas and snow-fed catchments (Nelson et al., 2023; Gupta et al., 2024).

Surface water and groundwater are interdependent parts of the hydrological cycle, historical studies of which

and contaminant transportation (Condon et al., 2021; Tsai, 2023). The tracer-based studies and isotopic tracing

also indicate recharge routes and routing times of different landscapes, which streamline more sustainable water

resource distribution (McKay, 2024; Nelson et al., 2023).

The quality of water is increasingly being posed by various traditional and emerging contaminants that are

making management strategies difficult to control and harmful to human health and the environment. Particularly

worrisome are emerging contaminants like per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, and

microplastics due to their persistence, the ability to bio accumulate, and inability to be treated using traditional

methods (Ma, 2022; Bradley et al., 2024). PFAS are found in drinking water and groundwater systems, wastes

discharged into waterways via effluents, and microplastics are vectors of toxic substances and microbial

due to especially high levels of nitrogen and phosphorus (O’Donnell et al., 2024; Konar et al., 2024). The primary

sources include agricultural run-off, urban stormwater and insufficient treatment of wastewater. The water

quality is also compromised by the rapid transport of sediments, which land use change and deforestation tend

to speed up and make water turbid, smother, and carry the attached pollutants (Segura et al., 2020; McKay,

2024).

climate-related shocks of drought, flood, and heatwave (Hagen, 2022; O'Donnell et al., 2024). Some of the

strategies are to diversify the water supply sources (e.g. groundwater banking, desalination, and wastewater

reuse), enhance water efficiency, and adopt dynamic governance models that dynamically respond to new data

(Nelson et al., 2023; Edwards, 2024).

Adaptation techniques like wetland restoration and afforestation have also been shown to have a positive impact

on managing hydrological extremes in addition to providing co-benefits such as carbon sequestration (Schramm

et al., 2024; Chang, 2016).

The raising of the sea level, intensification of storms, and adjustments in the precipitation patterns have made

the areas of coastal and flood plain susceptible (Behrangi et al., 2020; Segura et al., 2020). The structural

yet some of the most needed actions in very vulnerable coastal areas (Edwards, 2024; Nelson et al., 2023).

The framework of the water-energy-food nexus underlines the fact that resiliency in water systems cannot be