Half the world’s countries have degraded freshwater systems, UN finds

In half the world’s countries one or more types of freshwater ecosystems are degraded, including rivers, lakes and aquifers. River flow has significantly decreased, surface water bodies are shrinking or being lost, ambient water is growing more polluted, and water management is off-track. These are some of the findings of three reports tracking progress on freshwater, published on Wednesday 28 August 2024 by UN-Water and the UN Environment Programme (UNEP).

The triennial series of reports is focused on progress towards achieving the goal of “clean water and sanitation for all” (SDG 6) through protecting and restoring freshwater sources. Based on greater data sets than ever before, the reports reiterate the call to scale up support for Member States in tackling challenges through the UN System-wide strategy for water and sanitation and the accompanying upcoming Collaborative Implementation Plan.

“Our blue planet is being rapidly deprived of healthy freshwater bodies and resources, with dire prospects for food security, climate change and biodiversity,” said Dianna Kopansky, Head of the Freshwater and Wetlands Unit, Ecosystems Division at UNEP. “At this critical point, global political commitments for sustainable water management have never been higher, including through the passing of a water resolution at the last UN Environment Assembly in February, but they are not being matched by required finance or action. Protection and restoration policies, tailored for different regions, are halting further loss and show that reversing degradation is within reach. We absolutely need more of them.”

A reported 90 countries, most in Africa, Central- and Southeast Asia, are experiencing the degradation of one or more freshwater ecosystems. Other regions, such as Oceania, mark improvements. Pollution, dams, land conversion, over-abstraction and climate change contribute to degradation of freshwater ecosystems.

Influenced by climate change and land use, river flow has decreased in 402 basins worldwide – a fivefold increase since 2000. A much smaller number is gaining in river flow.

Loss of mangroves due to human activities (e.g., aquaculture and agriculture) poses a risk to coastal communities, freshwater resources, biodiversity, and climate due to their water filtration and carbon sequestering properties. Significant decreases of mangroves were reported in Southeast Asia, though the overall net rate of deforestation has leveled off in the last decade.

Lakes and other surface water bodies are shrinking or being lost entirely in 364 basins worldwide. A continued high level of particles and nutrients in many large lakes can lead to algal blooms and low-oxygen waters, primarily caused by land clearance and urbanization, and certain weather events.

Nevertheless, the construction of reservoirs contributes to a global net-gain in permanent water, mainly in regions like North America, Europe, and Asia.

Low levels of water quality monitoring

The poorest half of the world contributes under 3 per cent of global water quality data points, including only 4,500 lake quality measurements out of almost 250,000. This reveals an urgent need to improve monitoring capacity.

Lack of data on this scale means that by 2030 over half of humanity will live in countries that have inadequate water quality data to inform management decisions related to address drought, floods, impacts from wastewater effluents and agricultural runoff.

Where good data are available, it shows that freshwater quality has been degrading since 2017. Where data are lacking, the signs are not promising.

Report authors recommend the expansion and development of routine government-funded monitoring programmes, as well as incorporating citizen science into such national programmes, and exploring the potential of satellite-based Earth observation and modelled data products to help fill the data gap.

Inadequate progress on water resources management in over 100 countries

Balancing competing needs for sustainable water use from society and the economy requires the implementation of integrated water resources management (IWRM) across sectors, at all levels and across borders by 2030.

47 countries have fully reached or almost reached IWRM, 63 countries need to accelerate implementation, while 73 countries have only limited capacity for IWRM. At the current rate of reported progress, the world will only achieve sustainable water management by 2049. This means that by 2030 at least 3.3 billion people in over 100 countries are likely to have ineffective governance frameworks to balance competing water demands.

Solutions include unlocking finance through revenue raising and cost recovery arrangements, investments in infrastructure and management, as well as coordinated action, greater institutional capacity and better monitoring networks.