May 2011, Issue 48: Editors’ Notes

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This editorial is from the May issue of M&A’s Arizona Water Policy Update.

In the relatively small universe of truly renewable energy sources, hydropower has drawn little attention, until very recently. Although the negative environmental consequences of dams are well known, their ability to generate power around the clock make them a suitable source of reliable baseload power — a claim that cannot be made for unaided wind and solar.

Last month, government and industry analysts convened in Washington, D.C., to discuss the untapped potential for additional hydropower in the U.S. In general, opportunities for increasing capacity are found at smaller sites and at flood-control projects that can be retrofitted with power-generation equipment. To capitalize on these opportunities, bipartisan legislation has been introduced in the Senate to fast track and provide tax incentives for hydropower project applications. In addition, the Departments of Interior and Energy recently announced $26.6M in funding for hydropower retrofit projects.

Those pushing for renewed support for hydropower may soon rediscover why such initiatives in the West have not moved forward for many years. Fundamentally, a dam redefines the natural flow regime of its river. Managing releases to both simulate pre-dam seasonal flows and optimize hydroelectric output is difficult. According to USGS studies, attempts to simulate spring floods with planned high-flow releases from Glen Canyon Dam have generally benefitted the downstream ecosystem but have yielded mixed results for some critical species. Environmental groups are aware of these challenges and continue to collect data and develop models to predict the future impacts of existing dams. For example, the National Parks Conservation Association released a report in April cataloguing the impact of dams on the ecological systems of the Colorado River Basin. It is believed that these impacts will be exacerbated by climate change; Reclamation projects that Colorado River flows will be reduced on average by as much as 8.5 percent by the middle of 21st century (see “Shortage Planning” below). The new federal hydropower incentives are being proposed at a time when environmental groups are broadening their understanding of how dams impact river dynamics and ecosystem functions, and when drought, climate change, and a growing demand for water supplies are increasing the pressures on our river systems.

What is the future of hydropower in the West? Because it is not inherently a consumptive water use, there may be room for compromise by modifying the timing and magnitude of releases — if future tests show clear benefits to species of concern. Optimizing hydroelectric output under these modified release schedules must also be examined. The NPCA report proposes changes to dam operations that would benefit cultural and environmental resources and reportedly have “relatively minimal effects” on hydropower revenues. However, hydropower industry representatives at a House Committee hearing this week for Senate Bill 629, the Hydropower Improvement Act, are expected to claim that environmental regulations are often at odds with hydropower generation. Ultimately, Congressional action will either stimulate or stop the momentum toward new hydropower initiatives.

Juliet M. McKenna, MS, PG | Taylor D. Shipman, MS | Mark H. Myers, MBA