Three SDG 6 indicator progress reports highlight degradation in water related ecosystems

On 27 August, the UNEP and UN-Water’s Integrated Monitoring Initiative, in collaboration with partner agencies, published three reports on topics for which UNEP is the custodian agency. These reports provide overviews of progress on respectively ambient water quality with a special focus on health, the implementation of IWRM - with a special focus on climate change, and water-related ecosystems - with a special focus on biodiversity.

These three mid-term reports show an alarming lack of progress in achieving SDG 6, whereby the headline findings are amongst others, that in half of the world’s countries one or more types of freshwater ecosystems are degraded, including rivers, lakes and aquifers. Furthermore, data show that river flow has significantly decreased, surface water bodies are shrinking or being lost, and that ambient water is growing more polluted. Moreover, water management is off-track.

Each report is accompanied by its own set of visual summaries and videos.

The reports highlight the increased availability of data for decision making on indicators that have never been reported on globally before 2015. In that year, the UN established a fifteen-year initiative, known as the Integrated Monitoring Initiative for SDG 6 (IMI-SDG 6), as a support mechanism to track progress towards the goals of the 2030 Agenda for Sustainable Development. Progress on Sustainable Development Goal 6 (SDG6) on water and sanitation is measured through 11 indicators, which UNEP has classified into two classes: ‘tier 1’ - meaning there are methodologies established and data are regularly produced by a critical mass of countries, and ‘tier 2’ - meaning that only the methodologies have been established, but data on progress is not yet being regularly reported.

Because many of the indicators were new in 2015, and not yet being reported on at the global level, the IMI-SDG has progressed through four phases lasting three to four years each. In the first phase, the global baseline was set for the reporting, followed by a period in which - through information sharing and capacity building on data collection and reporting methodologies - national ownership of the process was built. The third phase was dedicated to integration and mainstreaming of the monitoring methodology, followed by consolidation and the application of the indicators to monitor sustainable development in the water sector in the fourth phase.

A good example of the strength of monitoring comes from the data on SDG indicator 6.6.1, which indicate that our freshwater ecosystems are in need of our attention and action. The target being monitored under SDG 6.6 is “by 2020, protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers and lakes”. To measure progress on this target, earth observations are used to determine changes to surface water bodies, such as lakes, large rivers, flooded wetlands and reservoirs. Countries may also incorporate a component on ecosystem health in their ecosystem monitoring programme, which is commonly measured through biological indicators.

Under SDG indicator 6.6.1, data is collected on the change in the extent of water-related ecosystems over time.

In 2020, SDG 6 data showed that 21% of the world’s water basins was experiencing rapid changes in the area covered by surface waters. At that time, 214 countries and areas had reported on these changes the previous five years. The 2024 midterm status report on SDG 6.6.1 shows that in 50% per cent of countries, currently, one or more water-related ecosystem types are in a state of degradation. This equates to more than 90 of the 185 countries reporting on indicator 6.6.1. These degraded ecosystems therefore deserve utmost attention in protection and restoration policies.

The growth in data on SDG 6.6.1 is facilitated through the update and use of Earth Observations (EO). Although EO is not yet capable of monitoring each and every basin on earth, according to UNEP it does currently collect enough satellite evidence from which to extract information on negative- or positive freshwater ecosystem changes and the extent of degradation of surface water and mangroves, the state of river flow and lake pollution.

In order to arrive at conclusions about the state of water related ecosystems, indicator 6.6.1 itself is subdivided into eight sub-indicators which each refer to a different aspect of the ecosystem. These are ‘river flow dynamics’, ‘permanent surface water extent dynamics’, ‘seasonal water extent dynamics’, ‘reservoir extent dynamics’, ‘water quality of large lakes: trophic state’, ‘water quality of large lakes: turbidity’, ‘inland wetland extent ‘and ‘mangrove area changes’. Each of these indicators is classified using a ‘traffic light’ colour system: the state of the ecosystems is identified as degraded (red), stable (orange), or improving (green), as compared to the baseline reference period.

It is on the basis of aggregation of national reporting on these sub-indicators that the 2024 SDG 6.6.1 midterm status report draws the conclusion that 50 per cent (90 out of of 185) countries have one or more water-related ecosystem type in a state of degradation. Also, as a result of land use changes and climate change, there has been a decrease of river flow in 402 basins worldwide -- a fivefold worsening since 2000.  

The report states that is abundantly clear that human interaction and the effects of climate change are the cause of the alarming increased degradation of freshwater systems. It is hoped that through the availability of high-quality data, the evidence is provided which may speed up of the protection and restoration of water related ecosystems at national and international levels.  

In the words of Alvario Lario, President of the International Fund for Agricultural Development (IFAD) and chair of UN-Water in his foreword to the report, “we face unprecedented challenges, but we now have unprecedented tools and political momentum. The data and insight gathered by the IMI-SDG6 must guide our prioritisation of efforts and investments to the areas of greatest need, ensuring no one is left behind.”