Restore freshwater ecosystems

Restoration is critical for freshwater systems

Restoration offers a powerful pathway to conserve freshwater ecosystems, secure water resources and sustain ecosystem services for current and future generations, while addressing the interconnected crises of climate change and biodiversity loss.

Although restored freshwater ecosystems often fail to reach the same level of ecosystem functioning and structure as undisturbed systems — making conservation the top priority — restoration remains essential for reversing environmental degradation, revitalizing nature and giving humanity a chance to build resilience against growing climate impacts.

Well-designed and appropriately implemented freshwater restoration can support climate mitigation and biodiversity conservation by restoring habitat and ecological connectivity for freshwater species. It can also provide life-sustaining ecosystem services to communities near and far, including protecting against intensifying climate impacts through flood protection and erosion control, and mitigating severe droughts by providing water sources during dry periods. Beyond environmental gains, well-designed and implemented habitat restoration efforts can also help reduce poverty, provide food security and support local economies through job creation and broader socioeconomic gains, including improved education, skills development and capacity-building.

The 2020-2030 U.N. Decade on Ecosystem Restoration is a collective effort to prevent, halt and reverse the degradation of ecosystems on every continent and throughout the world’s ocean. Freshwater ecosystems are among the most severely impacted, with one-third of natural freshwater systems having disappeared since the 1970s. As such, they must be a central focus of this global restoration effort.
 

Scaling restoration across freshwater ecosystems

Restoration will look different depending on the context — whether it is rewetting drained wetlands by reconnecting them with their original waterways, reducing impervious surfaces to enhance groundwater recharge, or removing dams to restore free-flowing rivers. Successful restoration will require an integrated approach that identifies and addresses the land-based drivers of degradation, including pollution from industrial activities, agricultural runoff, urban land-use and land cover changes.

Global data is still far too limited to regularly assess restoration progress for several key freshwater ecosystems — including wetlands (with the exception of mangroves and salt marshes), peatlands, rivers and lakes — underscoring the urgent need for improved global monitoring. For some of the ecosystem types where we do have data, we are far off track from meeting global climate and biodiversity targets. For example, mangrove restoration must accelerate more than tenfold, while an additional 15 million hectares (Mha) of peatlands must be restored by 2030. Although some gains have been observed in salt marsh restoration, there is insufficient data to determine whether these are enough to meet climate and biodiversity goals.

These are measures of gross gains in ecosystem extent. However, measures of ecosystem integrity are also essential for understanding the extent to which freshwater restoration efforts result in healthy, resilient and self-sustaining ecosystems. While global efforts to monitor ecosystem integrity are beginning to emerge, there is still no dedicated dataset that tracks this vital measure specifically for freshwater ecosystems.

To successfully scale and strengthen global restoration efforts, we must ensure that our underlying economic and political systems actively support and sustain meaningful, long-term impact. Given that many freshwater ecosystems and river basins span national borders — with approximately 60% of the world’s freshwater flows associated with transboundary rivers, lakes and aquifers — cooperation among countries is crucial for success.

Restoration must also be locally led and carried forward in partnership with Indigenous Peoples and Afro-descendant Peoples, who have long stewarded these ecosystems. Engaging their knowledge systems in respectful, ethical and reciprocal ways is essential to ensure that scientific and community expertise inform restoration together.