The Hydropower Puzzle: Anne Schedeen Illuminates Dams, Biodiversity, and the Future of Clean Energy

Anne Schedeen’s latest reporting unpacks the complex, often contradictory role of hydropower in the clean energy transition, revealing how aging dams reshape ecosystems, energy grids, and communities across the United States. Far from a simple solution, hydropower emerges as both a critical renewable stalwart and a growing environmental liability—burdened by outdated infrastructure, ecological disruption, and mounting climate pressures. Through sharp analysis and on-the-ground storytelling, Schedeen confronts the urgent need to modernize hydropower while balancing conservation and power generation.

Why Hydropower Remains a Cornerstone of America’s EnergyMix

Hydropower has long been a linchpin of American electricity, supplying roughly 7% of the nation’s renewable power and nearly 37% of all renewable generation, according to the U.S.

Department of Energy. With over 90,000 dams nationwide—most operational since the mid-20th century—hydroelectric facilities deliver reliable, carbon-free electricity to millions. “Hydropower is a workhorse,” Schedeen notes, “with the ability to scale output quickly and store energy through reservoir management—functions wind and solar still struggle to replicate at scale.” Despite modern challenges, hydropower remains indispensable: - Generates 40% of U.S.

renewable electricity and anchors regional grids - Provides essential flood control, water supply management, and recreational access - Offers grid stability unmatched by most other renewable sources This reliability has made aging dams vital to energy security—unless they face closures or repairs.

The Ecological Battleground: Dams’ Hidden Environmental Costs

Yet behind hydropower’s clean reputation lies a growing environmental toll. Dams fragment rivers, block fish migration, alter water temperatures, and trap sediment—disrupting natural nutrient cycles and undermining riparian habitats.

The Columbia River Basin, once teeming with salmon, exemplifies the damage: - Over 400 dams have reduced salmon populations by more than 90% in some stretches - Warmer reservoir water endangers cold-water fish species - Flooded forests and wetlands release stored carbon, counteracting climate benefits Schedeen highlights: “We can’t power our future without damaging the lifeblood of river ecosystems. It’s a reckoning the energy sector must face.” A 2023 study in *Science Advances* confirmed that buried dam legacies reduce riverine carbon sequestration by up to 60%, turning reservoirs from carbon sinks into sources. Modernizing the Relic: The Engineered Upgrade Imperative

Dammed rivers now stand at a crossroads: preserve aging infrastructure with costly, incremental fixes—or dismantle obsolete projects and restore natural flow.

Rehabilitation offers a path to extend dam lifespans while improving environmental outcomes. For example, controlled dam releases mimicking natural flood cycles can revive spawning grounds, as tested successfully on the Klamath River. Retrofitting also improves efficiency: upgraded turbines boost generation by 5–15%, maximizing energy output without new dams.

Yet the bare minimum isn’t enough. Schedeen warns: “Too many projects stop at minor repairs. True progress demands reimagining relics as ecological assets.” Since 2010, only 50 dams have been fully decommissioned—far short of the hundreds needed to heal river systems.

Community, Tribal Sovereignty, and the Human Face of Hydropower

For Indigenous nations and river-dependent communities, hydropower’s legacy is deeply personal. Many dams were built without consent, displacing families and flooding sacred lands—incidents threatening cultural continuity and self-determination. Schedeen documents this truth: “Dams are not just engineering feats; they’re human stories of loss and resilience.” Increasingly, tribal nations lead efforts to dismantle dams and restore Indigenous stewardship.

The Klamath Basin’s controversial removal of four massive dams—ETC, J.C. Boyle, and Copco No. 1 and 2—marks a breakthrough: approved in 2022 after decades of tribal advocacy, the project aims to revive salmon runs and honor ancestral waterways.

“The river’s return speaks to a deeper healing,” Schedeen observes. “It’s not just about fish—it’s about people reclaiming their relationship with water.” Similar efforts are emerging in the Pacific Northwest and California’s Central Valley, where communities demand a seat at the table during energy infrastructure decisions.

Climate Change Amplifies Risks—and Responsibilities

Climate change is reshaping hydropower’s viability.

Droughts reduce reservoir levels: Lake Mead, the nation’s largest hydropower site, operated at just 28% capacity in 2022, slashing generation by billions of kilowatt-hours. Conversely, extreme precipitation intensifies flooding, increasing dam failure risks. The U.S.

Army Corps of Engineers now classifies 30% of current hydropower dams as “high-risk” due to aging infrastructure and shifting weather patterns. Schedeen underscores this urgency: “Hydropower’s future isn’t just about energy—it’s about climate adaptation. Dams must survive both drought and deluge.” This dual threat pressures policymakers to accelerate modernization or accept growing energy and ecosystem vulnerabilities.

What’s Next? Balancing Clean Energy Ambition with Ecological Remediation

Reconciling hydropower’s promise with its burdens demands bold, balanced action. Schedeen advocates a Three-Pronged Strategy: 1.

Prioritize rehabilitation over relics—modernize key dams with fish passage, turbine efficiency, and ecological flows 2. Accelerate dam removal in ecologically critical basins, especially those with Indigenous-led restoration plans 3. Embed equity into policy: center tribal sovereignty, community input, and environmental justice in infrastructure decisions The path forward hinges on recognizing hydropower not as a static legacy, but as a dynamic resource—capable of supporting both climate resilience and river renewal if guided by science, ethics, and action.

As Anne Schedeen’s investigation makes unmistakably clear, the future of hydropower lies not in preserving the past, but in building a smarter, fairer river future—one that powers homes and restores wild landscapes in equal measure.