Water Scarcity is a Dual Threat: Quantity and Quality Demands Integrated Solutions
Category: Resource Management · Effect: Strong effect · Year: 2021
Global water scarcity is significantly underestimated when only considering water quantity, as degraded water quality exacerbates the problem and requires a broader approach to clean water technologies.
Design Takeaway
When designing water solutions, consider not just how much water is available, but also how clean it is, and explore technologies that can improve both aspects sustainably.
Why It Matters
Designers and engineers must recognize that water scarcity is not solely a supply issue. Solutions need to address both the availability and the potability of water resources, integrating quality considerations into the design of water management systems and technologies.
Key Finding
Water scarcity is worse than we think, affecting 40% of the world's population when water quality is considered alongside quantity. Technologies like desalination and wastewater reuse can help, but we need to manage their environmental and economic impacts.
Key Findings
- Including water quality increases the percentage of the global population experiencing severe water scarcity from 30% to 40%.
- Water quality impacts are particularly severe in regions like eastern China and India, where pollution from withdrawals degrades water sources.
- Expanding desalination and treated wastewater reuse can significantly reduce water scarcity, but their side effects (brine, energy, cost) require careful consideration.
Research Evidence
Aim: To quantify the impact of water quality degradation on global water scarcity and evaluate the potential of clean water technologies to alleviate it.
Method: Integrated modelling and scenario analysis
Procedure: The study modelled global water scarcity by incorporating both water quantity and water quality parameters (temperature, salinity, pollution, nutrients). It then simulated the expansion of desalination and treated wastewater reuse technologies to assess their impact on reducing the number of people affected by water scarcity.
Context: Global water resource management and clean water technology development
Design Principle
Holistic water resource design requires the integration of quantity and quality management strategies.
How to Apply
When designing a water purification system, evaluate its effectiveness not only in terms of volume treated but also in removing specific pollutants relevant to the local water source.
Limitations
The study's projections for technology expansion do not fully account for all technical and economic constraints.
Student Guide (IB Design Technology)
Simple Explanation: Water scarcity isn't just about not having enough water; it's also about the water we have being too polluted to use. New technologies can help, but we need to be smart about how we use them.
Why This Matters: Understanding the dual nature of water scarcity is crucial for developing effective and sustainable design solutions that truly address user needs and environmental challenges.
Critical Thinking: How might the 'side effects' of desalination and treated wastewater reuse, such as brine disposal and energy consumption, create new resource management challenges that designers need to address?
IA-Ready Paragraph: This research highlights that global water scarcity is a complex issue driven by both insufficient water quantity and degraded water quality. The study found that incorporating water quality parameters significantly increases the estimated proportion of the global population facing severe water scarcity, underscoring the need for design solutions that address both aspects holistically.
Project Tips
- When researching a water-related design problem, look for data on both water availability and water quality in your chosen region.
- Consider how your design solution might impact water quality, even if it's primarily focused on increasing supply.
How to Use in IA
- Reference this study to justify the importance of considering water quality in your design project, especially if it relates to water access or management.
Examiner Tips
- Demonstrate an understanding of the complex interplay between water quantity and quality in your design rationale.
Independent Variable: ["Expansion of clean water technologies (desalination, treated wastewater reuse)","Inclusion of water quality parameters"]
Dependent Variable: ["Number of people suffering from water scarcity","Percentage of world's population suffering from severe water scarcity"]
Controlled Variables: ["Water temperature","Salinity","Organic pollution","Nutrients","Sectoral water withdrawals"]
Strengths
- Integrates both water quantity and quality for a more comprehensive view of scarcity.
- Quantifies the potential impact of specific clean water technologies.
Critical Questions
- What are the most significant local water quality issues in my target region, and how do they interact with water availability?
- Beyond desalination and reuse, what other design interventions could address both water quantity and quality challenges?
Extended Essay Application
- Investigate the feasibility and environmental impact of implementing advanced water purification technologies in a specific region facing combined water quantity and quality issues.
Source
Global water scarcity including surface water quality and expansions of clean water technologies · Environmental Research Letters · 2021 · 10.1088/1748-9326/abbfc3