Recently released United Nations World Water Development Report, 2018 stressed upon Nature based solutions to address many of the world’s water challenges. These solutions are also aligned with the aims of the 2030 Agenda for Sustainable Development.

Report also says that Business-as-usual approaches to water security are no longer viable.

UN World Water Development Report

• The United Nations World Water Development Report (WWDR) is a global report that provides a comprehensive assessment of the world’s freshwater resources.
• It is produced annually by the World Water Assessment Programme and released by UN-Water.
• The Report examines the ways that the world’s water resources are being managed and the varied water problems that different regions of the world are experiencing.
• The Report also offers recommendations on how freshwater resources could be managed more sustainably.
• The topic of this year’s report is “Nature-based Solutions for Water“.

The world’s water: challenges

• The world’s population is expected to increase to nearly 10 billion people by 2050, with two-thirds of them living in cities.
• The global demand for water has been increasing at a rate of about 1% per year over the past decades as a function of population growth, economic development and changing consumption patterns.
• Industrial and domestic demand for water will increase much faster. An estimated 80% of industrial and municipal wastewater is released without any prior treatment, with harmful impacts on human health and ecosystems.
• The global water cycle is intensifying due to climate change, with wetter regions generally becoming wetter and drier regions becoming even drier.
• Ecosystem degradation is a leading cause of increasing water resources management challenges. Urbanisation, de-forestation, intensification of agriculture has further added to the existing water challenges.
• The International Water Management Institute estimates that total demand could increase from 680 billion cubic metres (BCM) to 833 BCM by 2025 and to 900 BCM by 2050.
• India also faces major threats to its water security, with most water bodies near urban centres heavily polluted. A Central Pollution Control Board report indicates that almost half of India’s inter-State rivers are polluted.
• Inter-State disputes over river resources are also becoming more intense and widespread.

How can Nature-based solutions address water challenges?

• Goal 6 of the 2030 Agenda for Sustainable Development recognises the importance of sustainable management of water and sanitation.
• Nature-based solutions are essential to meet this goal.
• Nature-based solutions (NBS) are supported by nature and use natural processes to contribute to the improved management of water.
• An NBS can involve conserving or rehabilitating natural ecosystems and can be applied both at micro and macro levels.
• NBS support a circular economy that is restorative and regenerative by design and promotes greater resource productivity. NBS aims to reduce waste and avoid pollution, including through reuse and recycling.
• Green infrastructure for water refers to the natural systems that provide water resources management is the application of NBS.
• Reducing Emissions from Deforestation and Forest Degradation (REDD+) is the application of a nature-based approach for managing the global climate.
• NBS also offer opportunities to reduce conflicts between sectors over water use through improved system performance.

Different types of NBS solutions

• Natural methods like reforestation and forest conservation, reconnecting rivers to flood plains, wetland restoration and water harvesting will regulate the water supply.
• Agricultural systems that conserve ecosystem services by using practices such as conservation tillage, crop diversification, legume intensification and biological pest control.
• The environmental co-benefits of nature-based solutions decrease pressures on land conversion and reduced pollution, erosion and water requirements.
• Constructed wetlands for wastewater treatment can also be a cost-effective and provides adequate supply of water for irrigation and additional benefits that include energy production.
• Natural and constructed wetlands also biodegrade or immobilise a range of emerging pollutants.
• Watershed management is another nature-based solution that will spur local economic development, job creation, biodiversity protection and climate resilience.
• NBS for addressing water availability in urban settlements are of great importance. . Managing water flows through urban landscapes can improve water resources availability.
• Catchment management outside urban areas, improved recycling of water within urban water cycles, green infrastructure within urban boundaries are some of the Nature based solutions for improving water resources availability.

Way forward

• Nature-based solutions are closely aligned with traditional and local knowledge including those held by indigenous and tribal peoples in the context of water variability and change.
• Effective NBS require Intersectoral collaboration, for example between those working with water management, agriculture, forestry, urban planning, and ecological protection.
• Harmonizing multiple policy areas at global, international, national, provincial and local scales is a key need for sustainable development. NBS offer a means to operationalize policy across scales.
• NBS applications need to be based less on generalized assumptions, and better assessed and designed specifically for local applications.