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Adaptive management provides climate change tool

According to a recently published report, Climate Change and Water Resources Management: A Federal Perspective, using adaptive management of water resources can help managers make decisions sequentially over time. This strategy can be useful for coping with uncertainties brought about by climate change, the report says.

 

This 76-page report was prepared by the U.S. Geological Survey, the National Oceanic and Atmospheric Administration, the U.S. Army Corps of Engineers, and the U.S. Department of the Interior’s Bureau of Reclamation. These agencies are charged with weather prediction and water resources management.

 

The purpose of this report was to explore strategies for improving water management by tracking, anticipating, and responding to climate change. Because climate change likely will affect the hydrological cycle, it may have a large effect on water resources and water resource managers.

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The report calls for a policy of heightened monitoring and adaptive management of resources to prepare for anticipated climate change from global warming. The agencies said the report presents the best available science to help better manage and preserve the nation’s water resources in the face of a changing climate.

 

The report said long-term networks designed to monitor climate change are critical for detecting and quantifying changes over time and their effects. It said monitoring needs to focus on locations that describe the “climate signal,” such as upstream and downstream from major water management infrastructure or in vulnerable ecological reaches.

 

The agencies involved in preparing the report said adaptation options in the face of climate change include operational, demand management, and infrastructure changes to the water resources system.

 

“This report is a first step,” the document says. “The agencies will next address the knowledge, technology, and research gaps, and the monitoring strategies for improving understanding and aiding in decision-making. Although the report does not offer recommendations, it does lay a foundation for future climate change actions.”

– The report is available on the Internet at http://pubs.usgs.gov/circ/1331.

 

Assessment shows small hydro potential in Oregon

According to results of a recent report developed for Energy Trust of Oregon, opportunities exist in the state for development of hydro projects with a capacity of less than 20 MW. However, the report – entitled Small Hydropower Technology and Market Assessment – indicates several actions need to be taken to stimulate the market, including changing the permitting process.

 

With this 127-page report, Energy Trust of Oregon wanted to develop an understanding of:

 

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The report indicates there are three main opportunities for development of hydro projects with a capacity of less than 20 MW in Oregon: piggybacking on existing diversions (to avoid the need to obtain new water rights), leveraging planned construction processes (to minimize costs), and accessing year-round water for irrigation district projects (to make projects economically viable).

 

Energy Trust of Oregon is a non-profit corporation that invests state funds in renewable energy and energy efficiency under an agreement with the Oregon Public Utility Commission. The trust offers incentives for small hydro project development through its Open Solicitation program, such as financing for feasibility studies and limited technical assistance to organizations interested in developing a project.

 

With the above opportunities in mind, the report indicates there are four short-term actions that can be taken to stimulate the market for small hydro in Oregon:

 

Summit Blue Consulting LLC of Boulder, Colo., conducted the assessment and issued the report under a $60,000 contract with Energy Trust of Oregon.

– The report is available on the Internet at www.energytrust.org/library/reports/090126_Small_Hydropower.pdf.

USSD releases report on earthquake motion at dams

The U.S. Society on Dams (USSD) announces availability of a report: Strong Earthquake Motions at Dams.

 

There have been major improvements in the measurement, processing, dissemination, and use of strong motion data in recent years, the report says. It also says that improved technology and cooperation among many agencies make strong motion data available on the Internet minutes after earthquakes occur.

 

The report is intended to provide guidance and references on installing, using, and maintaining strong motion instruments and sources of recorded earthquake motions at dams.

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Topics covered in the report include:

 

This report updates and expands the scope of a 1989 report, Strong Motion Instruments at Dams. A subcommittee of the USSD Committee on Earthquakes prepared the current report.

– The report costs US$12 for USSD members and US$20 for non-members. To order, visit the website: www.ussdams.org/pubs.html.

Appalachian Power develops low flow operating protocol

To determine how flows from the 636-MW Smith Mountain pumped-storage project should be managed in the future, Appalachian Power Company is developing a probability-based operating protocol. This protocol is to be used during periods of low inflow to balance competing downstream water use.

 

Implementation of probability-based triggers will enable flows from the project to be reduced earlier but to a lesser degree than what occurred during past periods of low inflow, says Teresa Rogers, relicensing coordinator for American Electric Power (AEP). Appalachian Power is a division of AEP.

 

The Smith Mountain project is located in the headwaters of the Roanoke River Basin in Virginia. This area recently has experienced significant drought conditions, which intensifies competition for water use, Rogers says. In addition, development in the area has accelerated over the past 15 years, leading to greater concerns about lake levels, water supply, and downstream flows for recreation and fish habitat. In the face of these challenges, Appalachian Power needed to determine how flows from the Smith Mountain project should be managed to meet the various demands on the available water, particularly in times of low flow.

 

Appalachian Power hired HydroLogics in Raleigh, N.C., to develop a hydrologic model for the Smith Mountain project, and to then use the model to facilitate development of the low flow operating protocol.

 

The basin-wide hydrologic model, called RRBROM, simulates an 80-year inflow record to capture as many drought events as possible. The model is used to assess the effects of implementing different trigger strategies on reservoir levels and instream flows. The triggers were developed in an open, collaborative process with stakeholders, Rogers says.

 

The protocol uses the model, along with “ensemble” forecasts (i.e., multiple, equally likely forecasts of up to a year in duration), to develop three probability-based triggers. A trigger is activated when the forecasted lake level has an “X” percent chance of reaching a level of “Y” within “Z” weeks. For example, one trigger is a 20 percent chance of lake level dropping below 790.5 feet in 16 weeks. Activation of a trigger leads to a specified drought response. For this trigger, the target flow is 85 percent of the dry year target or the floor (the absolute minimum acceptable for maintenance of aquatic habitat), whichever is higher.

 

These probability-based triggers reduce the chances of taking corrective action prematurely because they account for time of year and the inflows leading up to and projected to occur from that point in time, Rogers says.

 

The Smith Mountain project began operating in the 1960s. The project’s Federal Energy Regulatory Commission operating license expires in 2010. AEP will include the protocol in its application for a new license.

 

 

 

Hydro Review always welcomes your suggestions for magazine articles and departments you believe would be helpful to colleagues.

Please send your ideas to the Editor, Hydro Review, 410 Archibald Street, Suite 100, Kansas City, MO 64111-3046; (1) 816-931-1311, extension 106; E-mail: marlab@pennwell.com.

 


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