The water footprint is commonly defined as the total volume of freshwater consumed and polluted at various levels (e.g., national, corporate, or product levels). Water footprints have proven useful in identifying areas of unsustainable water use, and can guide policy decisions aimed at reducing water stress. They are an effective tool for raising awareness among consumers, producers, and policymakers about the environmental impacts of water use. They can also support strategies for redistributing water resources through virtual water trade. This literature review aims to assess the capabilities and challenges associated with the application of water footprint methodologies in different contexts, with a focus on their role in sustainable water management. Future research and development should focus on addressing the identified challenges to enhance the utility of the water footprint concept for consumers, producers and policy makers.

The UNDP is implementing the project “Conservation and sustainable management of lakes, wetlands, and riparian corridors as pillars of a resilient and land degradation-neutral Aral basin landscape supporting sustainable livelihoods” to enhance the resilience of the ecosystems and livelihoods in Lower Amudarya and Aral Sea Basin (LADAB) through land degradation neutrality (LDN) compatible integrated land-water management.

This assignment contributes to water allocation analysis and the development of water supply scenarios for irrigated agriculture and biodiversity conservation reports. The services consist in:

  1. Consulting with project experts, government agencies, local communities, and other relevant stakeholders
  2. Develop a hydro-economic water allocation model for the lower Amu Darya basin using WEAP
  3. Explore different scenarios for irrigated agriculture and biodiversity conservation, considering climate change, to strike a balance between sustainable agricultural practices and conservation of biodiversity and ecosystems and (iv) build capacity and support project experts and relevant stakeholders on water allocation analysis and modelling.
Stakeholders consultation in Nukus, Uzbekistan

Most recent research has focused on identifying historical megadroughts based on paleo-records and understanding their climatic causes, or on the study of “modern” events and their impacts, generally in lowland and plain regions. However, high-mountain regions and snow-dependent catchments have been little studied, and little is known about the impact of megadroughts on the state and dynamics of the cryosphere in mountain water towers.  

In general, catchments dependent on high mountain systems have an intrinsic capacity to buffer the lack of precipitation and excess evapotranspiration that depends on the water reserves stored in the cryosphere (snow, glaciers and permafrost). It is presumed that the this buffer capacity is limited until a tipping point is reached from which the impacts of water shortages and temperature extremes may be amplified and jeopardize the functioning of ecosystems and water resource systems. 

MegaWat has a two-fold objective: 1) to address the knowledge gaps around the hydro-climatic causes of extreme droughts and their impact on the water balance of Europe’s mountain water towers, with special emphasis on the concurrence of compound events and cascading and multi-scale effects, and 2) to develop and propose new adaptation strategies to cope with the duration, extent and severity of future megadroughts and their potential impacts on environmental and socio-economic assets.  

For its implementation, MegaWat focuses on Europe’s high mountain regions and their dependent-catchments. MegaWat aims to develop three products:  

  • Product 1. A methodological framework for the identification and characterization of historical megadroughts during the instrumental period, and the assessment of the role of the cryosphere in supporting the landscape development of downstream areas, or in buffering climate change impacts. Product 1 relies on a combination of climate regionalization, surface energy balance modelling, hydrological simulation, and water evaluation and allocation analysis at the catchment level (Figure 1).  
  • Product 2. A high-resolution, open-access regionalized climate database.  
  • Product 3. A list of potential adaptation strategies useful for the prevention and mitigation of drought impacts, and the enhancement of the water security and resilience of high mountain regions and dependent catchments. These scenarios will be agreed with regional and local actors and stakeholders, and their effectiveness will be evaluated under extreme drought scenarios in three pilot regions in Europe. These pilot regions will be previously selected following criteria of representativeness, strategic importance and vulnerability to droughts.  

FutureWater plays an important role in MegaWat by coordinating the Work Package which aims to develop and test simulation tools that help to adapt to megadroughts and support the decision making process. Two specific objectives are pursued in this Work Package: a) the development of a methodological prototype for quantifying impacts and identifying tipping points for water security in snow-dependent downstream catchments, and b) the generation and the integration of snow drought indicators in the FW’s Drought Early Warning System called InfoSequia (Figure 2). 

Schematic representation of a high mountain basin, including the main components, processes and impacts related to droughts. 
Workflow of the InfoSequia Early Warning System developed by FutureWater and adapted for the detection of tipping-points of water scarcity in snow-dependent catchments. More information about InfoSequia.

One-pager can be downloaded here.

Aknowledgements  

This project has received funding from the Water4All programme with co-funding from CDTI (Spanish Office for Science and Technology) and the EU’s Horizon Europe Framework Programme for Research and Innovation”. 

The WEAP model simulates water availability, supply, and demand on a small scale for over 40 irrigation, domestic, and industrial sites, running on a daily timestep to include detailed reservoir operations and water use abstractions. The updated WEAP model was co-designed together with ARA-Sul, the regional water authorities of southern Mozambique. Monthly meetings were held to support information sharing and co-ownership throughout the project.

The model will aid ARA-Sul in water accounting and the licensing of water users served by the Pequenos Libombos Reservoir. The Pequenos Libombos Reservoir, with a storage capacity of 350 MCM, is the main water supplier to the Maputo Metropolitan Area inhabited by over 3 million people. In June 2024 sessions were held in The Netherlands were ARA-Sul was trained in the usage of the model.

The cover picture was taken by David Mucambe (ARA-Sul).

The aim is to develop a business case for a Watershed Investment Program for Addis Ababa. It includes stakeholder and governance analysis, scientific modeling, return on investment (ROI) analysis, and an implementation plan. Hydrological models are employed to assess the potential of Nature-based Solutions to mitigate the negative trends in the watershed, and improve water supply reliability, water quality, sedimentation and agricultural productivity. The study should raise awareness for all key stakeholders and potential investors. The study is performed under the Nature for Water Facility launched by The Nature Conservancy.

Urban flood management in Laos is typically based on a limited, hard infrastructure approach. With the aim to shift this paradigm towards an integrated approach that enhances climate resilience, the project “Building resilience of urban populations with ecosystem-based solutions in Lao PDR” was approved by the Green Climate Fund Board in November 2019 with a GCF grant of US$10 million. United Nations Environment Programme (UNEP) serves as the Accredited Entity for the project. Activities are executed by the State of Lao PDR through the Ministry of Finance and Ministry of Natural Resources and Environment (MONRE) as well as UNEP. The project is implemented across five years (2020-2025) covering four provincial capitals in the country: Vientiane, Paksan, Savannakhet, and Pakse.

One component of the project involves technical and institutional capacity building to plan, design, implement and maintain integrated urban Ecosystems-based Adaptation (EbA) interventions for the reduction of climate change induced flooding. As a part of Integrated Climate-resilient Flood Management Strategy (ICFMS) development, the project conducts hydrological, hydraulic and climate risk assessments to inform climate change adaptation solutions for risk reduction in Vientiane, Paksan, Savannakhet and Pakse.

A consortium of FutureWater, Mekong Modelling Associates (MMA) and Lao Consulting Group (LCG) was contracted by MONRE to implement the related activities. FutureWater leads and coordinates this assignment and contributes remote sensing analyses with state-of-the-art innovative tools, climate risk assessments, and training activities. To ensure sustainability and effective technology transfer, the modelling and mapping infrastructure and trained staff will be hosted within MONRE and a knowledge hub that is established within the National University of Laos.

 

Southern Spain is a highly productive agricultural region, but with huge challenges around water scarcity and environmental sustainability. There is a demand in the agricultural sector to work towards water stewardship in Spain. The Alliance for Water Stewardship has developed a Standard which helps retailers and their suppliers to cause change at scale. This approach recognizes that there are common challenges that could be more easily overcome through a collective, place-based approach.

In the Doñana region, berry farms and groundwater usage are causing a conflict with the unique ecosystems in the National Park. A catchment assessment and active stakeholder engagement is needed as a first step in this region to work towards water stewardship. The catchment assessment will provide information on the catchment context, in line with the requirements of the Standard. The purpose of the assessment is to reduce the burden on agricultural sites by providing them with a common set of information which they and others can use to inform responses to their shared water challenges.

Within the project we cooperate with the hydrologists of ARA-Norte to discuss and establish the baseline for a water system analysis in the Monapo Catchment. Following discussion and mapping sessions, FutureWater is developing a Water Allocation Model in WEAP that includes climate change scenarios and mitigation and adaptation measures to asses the water availability of the catchment. Part of the assignment includes continuous training to local professional, to ensure the application of the developed model in the analysis of the system and elaborating specific proposal for implementation in the region.

Nigeria as a country faces extensive Water Security Challenges (WSCs), from water availability and provisioning to water quality issues. These will become exacerbated by multiple future pressures, including huge increases in population and a changing climate. Oshun and Ogun catchments are located in the South West of Nigeria, in the same area as Lagos. These catchments face multiple challenges including unregulated groundwater extraction and poor sanitation infrastructure which compromise societal access to water.

NbS have the potential to contibute to addressing WSCs by increasing the overall resilience of the hydrological system, helping to increase infiltration to groundwater and buffer water quality issues. Alongside this, NbS can provide a wealth of co-benefits including carbon sequestration and increased biodiversity, complementing more traditional so-called ‘grey’ infrastructure such as pipelines and treatment plants.

Through extensive stakeholder consultation paired with GIS analysis and hydrological modelling, this project will help outline NbS which are best placed to address key WSCs, alongside identifying beneficiaries in the catchments of interest and existing parnerships in the catchment which are capable of delivering projects on-the-ground.

This work lays the foundations for the creation of so-called Watershed Investment Programmes (WIPs) in Osun and Ogun catchments, alongside the identification of further catchments in Nigeria which are disposed towards similar initiatives. WIPs aim to sustain and enhance the provisioning of key water-related ecosystem services by funding the conservation and restoration of lands that protect water quantity and quality. This is achieved through connecting downstream water users (e.g. water utilities, local governments, businesses, and the public) to upstream land managers (e.g. farmers and rural landowners). They unite these parties and others around the goal of enhancing water quality and quantity for societal benefits.

This consultancy project is framed by the AQUIFER project, “Innovative instruments for the integrated management of groundwater in a context of increasing scarcity of water resources” (Interreg-SUDOE V programme) which aims to capitalize, test, disseminate and transfer innovative practices for the preservation, monitoring and integrated management of aquifers.

FutureWater expertise was required for providing a novel and open-source hydrological modelling framework able to quantify spatial patterns of daily root percolation as a direct surrogate of groundwater recharge in the Campo de Cartagena Quaternary Aquifer (CC-QA). This aquifer is located at SE Spain and is one of the most important vectors of water drainage to the Mar Menor lagoon.

This task is addressed through the improvement and local calibration of the SPHY code for the Campo de Cartagena and the simulation of the water balance in the soil root zone from the 1950s until the end 2020. The SPHY-Campo de Cartagena includes a new routine able to compute irrigation inputs at the pixel level based on satellite data. Timeseries of monthly root percolation are taken as good surrogates of potential groundwater recharge and used as the main forcing input to an hydrogeological model of the Quaternary aquifer. The calibration process is performed through a sensititivity-intercomparison analysis in which model-derived outputs (irrigation and streamflow) during the calibration period are cross-checked against actual observations.

Spatial patterns of root percolation and the relative contribution of irrigation return flows to the total groundwater recharge were quantified (e.g. Figure 1) under historical and current conditions. Simulation results would show the lack of a significant temporal trend in the long-term recharge rates in the aquifer, most likely due to the the strong interannual variability observed in rainfall patterns, but also by the trade-offs resulting from the combination of climate, land use and irrigation-crop management drivers.

Figure 1. Mean Annual values of the main water balance components in Campo de Cartagena (2000-2020). RPer_ratio refers to the fraction between Root Percolation (MA.RPer) and Precipitation (MA.Pre)