In the heart of Yosemite National Park, where granite cliffs rise above ancient forests and waterfalls cascade into deep valleys, lies a quieter kind of wonder: Ackerson Meadow. One of the largest mid-elevation meadows in the Sierra Nevada, and the largest in Yosemite, it is a place of stillness, wildlife and ecological importance. But for more than a century, this landscape was slowly being drained, eroded and diminished by human activity.In 2023, a landmark restoration project began. By June 2025, it had become the largest wetland restoration effort in Yosemite’s history; and the largest, by fill volume, ever undertaken in the Sierra Nevada. The results were transformative: 94 acres of lost wetlands restored, 84 additional acres protected and a 230-acre headwater meadow system returned to self-sustaining hydrologic function, according to a report on NPS.gov.A meadow in crisisAckerson Meadow is an ecologically critical wildlife corridor and habitat for several at-risk species, including the state-endangered great grey owl and little willow flycatcher. Yet for decades, a massive erosion gully network, up to two miles long, 14 feet deep and 100 feet wide, had been draining the meadow’s wetlands.The gully was the result of over a century of landscape manipulation, including domestic water diversion, farming, ranching and timber harvest. It had already drained 90 acres of wetlands and was actively eroding an additional 100 acres. Without intervention, the meadow’s ecological functions, including water storage, flood protection, wildlife habitat and carbon sequestration, would continue to decline.In 2016, Ackerson Meadow was purchased from private ownership and donated to Yosemite by a coalition including the Trust for Public Lands, National Park Trust, Yosemite Conservancy and American Rivers. The stage was set for restoration, as per the report.Filling the gully, restoring the flow

Yosemite National Park

Between August 2023 and June 2025, a partnership of Yosemite National Park, Stanislaus National Forest, American Rivers and Yosemite Conservancy implemented a bold plan: fill the erosion gully to the elevation of the surrounding meadow.The team filled 18,538 linear feet, 3.51 miles, of gully with 162,000 cubic yards of locally sourced material. This included 132,900 cubic yards of mineral soil combined with 29,100 cubic yards of woodchips. The “full fill” approach was chosen because it offered rapid, comprehensive restoration of the wetland area lost to human impacts, protected remaining intact wetlands and was expected to become a self-sustaining ecosystem within three to five years, requiring minimal long-term maintenance.The work was carried out in two phases. Phase 1, from August to November 2023, focused on filling the gully in the lower half of main Ackerson Meadow and the full extent of the gully in south Ackerson Meadow. Phase 2, from August to November 2024, completed the fill in the main meadow. Revegetation followed each phase in the spring of 2024 and 2025.Bringing the meadow back to lifeRestoring the land was only part of the work. The team also replanted the meadow with native species to ensure the ecosystem could thrive. Revegetation efforts included:– Broadcast seeding of more than 117 pounds of native, locally collected seed from 25 plant species– Installation of 434,000 wetland container plants, including species such as Scirpus microcarpus, Juncus dubius and Carex athrostachya– Harvest and replanting of wetland sod and 600 whole-plant willows– Restoration of 15.11 acres of borrow area with broadcast seeding, mulching and planting of 170 black oak saplingsThe result was a meadow reborn, one that could once again support the wildlife and ecological processes that had defined it for millennia.Benefits for wildlife, water and climateThe restoration provides outstanding long-term benefits for rare and endangered species, including the Pacific fisher (federally endangered), northwest pond turtle (proposed federally threatened), great grey owl (California endangered) and little willow flycatcher (California endangered). It also supports a diverse suite of native songbirds.Beyond wildlife, the project improves water quality and drinking water supply, increases groundwater storage, sequesters carbon and enhances resilience to drought and wildfire. The healthy headwater system helps mitigate the impacts of drought and floods on downstream communities within the Tuolumne River watershed, including the cities of Turlock and Modesto.The project also aligns with California’s 30 by 30 Initiative, which aims to protect 30% of the state’s land and coastal waters by 2030, and supports the Sierra Meadow Partnership goal to restore 30,000 acres of meadow by 2030, as per the report.A collaborative effortThis monumental project was made possible through the collaboration of multiple partners, including American Rivers, the National Park Service, the U.S. Forest Service, Yosemite Conservancy and numerous funding organisations such as the California Department of Fish and Wildlife, Google, the National Park Foundation and the Bipartisan Infrastructure Law, as per NPS.Tribal participation was also a key component. The National Park Service initiated consultation with seven associated American Indian tribes and groups in October 2017. Tribal members participated in revegetation, beaver dam analogue development and on-site resource protection throughout the project.Volunteers played a vital role as well. In 2021 and 2022 combined, 167 volunteers provided 3,145 hours of support. In 2023, 137 volunteers contributed 2,018 hours. In 2024, 233 volunteers provided 2,933 hours, and in 2025, 44 volunteers contributed 689 hours.A model for the futureAckerson Meadow is now a living example of what is possible when science, partnership and community come together. Research studies are ongoing, including USGS-led work on topography, vegetation and habitat structure change, as well as soil carbon sequestration studies to improve decision-support tools for future restoration projects.The meadow’s recovery is not just a victory for Yosemite. It is a model for wetland restoration across the Sierra Nevada and beyond; a reminder that even landscapes scarred by a century of human impact can be healed, given time, care and commitment.Today, Ackerson Meadow is a living testament to what happens when we choose restoration over degradation and protection over exploitation. It’s a place where water is flowing again, wildlife is thriving and the future of the Sierra Nevada looks a little brighter.