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Dam Safety & Security

Government awards contract for Folsom Dam modifications

The Bureau of Reclamation awarded a $3.2 million construction contract for dam safety modifications planned for Folsom Dam, on California’s American River.

DD-M Crane and Rigging, Alameda, Calif., the contractor, is to perform the work as part of a larger dam safety program at the dam. It will modify Dike 5, an earthen embankment feature on the north shore of Folsom Reservoir. Principal work will include partial removal of the downstream face of the dike to add filters and drains to control internal erosion.

Site preparation, including trail relocation and development of the contractor’s use area, began in May and will continue until about Labor Day, September 1.

Reclamation anticipates principal construction work on Dike 5 will begin after Labor Day. It expects the contracted work will be completed in spring 2009. Some construction activities will be limited to certain periods to maintain dam safety and operational and recreational requirements, Reclamation said.

The work is part of a multi-year construction program to perform safety modifications at Folsom Dam and Reservoir.

Another component of the program involves building an auxiliary spillway to increase flood protection at the dam. Construction of the auxiliary spillway – being built as a Joint Federal Project by Reclamation, the U.S. Army Corps of Engineers, California Department of Water Resources, and Sacramento Area Flood Control Agency – began in January 2008. Kiewit Pacific Co. of Concord, Calif., is construction contractor.

The auxiliary spillway is to address the hydrologic risk to Folsom Dam identified through Reclamation's Safety of Dams program. It also is to achieve the Corps' objective to double protection for the city of Sacramento, to a 200-year flood.

Security guide informs dam owners, operators

A dam security guide prepared for dam owners and operators presents indicators of surveillance and suspicious activity, and how to report such activity.

The Dams Sector Security Awareness Guide includes a list of more than three dozen indicators of suspicious activities, such as: people possessing or using night-vision devices near the dam perimeter or in the local area; people parking, standing, or loitering in the same area over multiple days with no apparent reasonable explanation; and non-military people seen with military-style weapons and clothing or equipment.

The guide also discusses procedures for reporting suspicious incidents and activity.

The Dams Sector Security Education Workgroup initiated development of the guide to help owners and operators maintain security awareness. Representatives of the Dams Sector Coordinating Council, Dams Sector Government Coordinating Council, and the U.S. Department of Homeland Security formed the workgroup. The Association of State Dam Safety Officials contributed to the guide.

– The guide is available from Homeland Security by sending an e-mail to dams@dhs.gov. It also is available on ASDSO’s Internet site, www.damsafety.org; go to the "Publications and Resources" link, choose "Download Documents," and click on "Dams Sector Security Awareness Guide" below "State and National Program Information."

Canadian dam group to address dam decommissioning

The Canadian Dam Association (CDA) said it plans to prepare a technical bulletin examining issues associated with dam decommissioning and the environment.

CDA said the association, through its Dam Safety Committee, would establish a working group to look at the issues and to develop a technical bulletin.

The association noted there are instances where societal values could weigh in the balance to decommission structures to restore fish passage and natural ecosystems.

CDA said its 2007 Dam Safety Guidelines, based on a life-cycle approach, provide the overarching principles regarding issues associated with decommissioning and the environment. However, it added, it has no technical bulletins specific to those aspects of dam safety.

Dam organizations announce plans for annual conferences

Two North American dam organizations announce plans for their 2008 annual conferences.

Association of State Dam Safety Officials

The Association of State Dam Safety Officials (ASDSO) meets Sept. 7-11 in Indian Wells, Calif. ASDSO anticipates about 850 people will attend.

The program features concurrent technical paper presentations on a variety of topics associated with dams, including rehabilitation, failures, removal and environmental issues, regulations, emergency action planning, geotechnical issues, hydrology and hydraulics, seismic issues, and roller-compacted concrete.

In addition, the conference features an exhibition of companies providing services and equipment to the dam industry.

As part of the conference, ASDSO organized a field trip to the Metropolitan Water District of Southern California’s Eastside Reservoir.

The conference agenda and registration information is on the Internet: www.damsafety.org.

Canadian Dam Association

The Canadian Dam Association (CDA) meets Sept. 27-Oct. 2 in Winnipeg, Manitoba. The conference theme is "Emerging Technologies for Dams."

Several sessions throughout the conference will feature new and emerging technologies in dam engineering throughout the world. The conference also will feature an exhibition of companies providing services and equipment to the dam industry.

As part of the conference, CDA is offering pre-conference workshops on: CDA’s Dam Safety Guidelines and Dam Safety Regulation; Risk and Uncertainty in Dam Safety; and Real Time Instrumentation Monitoring. Post-conference technical tours are available to: Winnipeg’s Red River floodway expansion project and St. Andrews Lock and Dam; hydroelectric plants in southern Manitoba; hydroelectric plants in northern Manitoba; and Northern Manitoba tailings facilities.

Information about registration is available on the Internet at www. cda2008.ca.

USSD names new officers; presents awards, scholarships

Officers for the U.S. Society on Dams (USSD) for 2008-2009 are: Kenneth A. Steele of the San Diego County Water Authority, San Diego, Calif., president; Daniel J. Hertel, Barnard Construction Co., Bozeman, Mont., vice president; and Douglas D. Boyer of the Federal Energy Regulatory Commission (FERC), Portland, Ore., secretary-treasurer.

Board members re-elected for another term are: Donald L. Basham, Stantec Consultants, Topsham, Maine, and Daniel J. Mahoney, FERC, Washington. New board members are: Keith A. Ferguson, Kleinfelder Inc., Golden, Colo., and Bruce C. Muller Jr., U.S. Department of Interior’s Bureau of Reclamation, Denver, Colo.

Officers and board members were announced at USSD’s 2008 annual meeting and conference in Portland, Ore. More than 350 engineers, managers, and scientists involved in the design, construction, operation, and safety of dams attended the conference.

During the meeting, USSD presented multiple awards:

– Award of Excellence in the Constructed Project to Lake Brazos Labyrinth Weir, near Waco, Texas. The labyrinth weir replaced a gated spillway and overflow embankment on the Brazos River near downtown Waco, eliminating operation and maintenance problems that plagued spillway gates. The new 3,000-foot-long labyrinth weir was built in phases within the footprint of an existing dam to accommodate regulatory requirements and reduce costs. Construction was completed in less than two years at a final cost of $16.4 million. The award recognized: the city of Waco, the owner; Archer Western Contractors Ltd., the contractor; and Freese and Nichols Inc., the consultant.

– Scholarships to three students: Robert Jaeger, a graduate student at the University of California, Davis; Rachael Bisnett, Purdue University; and, Brian Crookston, Utah State University. Jaeger received a $10,000 scholarship to support his research on development of a variable rate cone penetration test for assessing the presence and engineering properties of intermediate Soils in dams and levees. Bisnett and Crookston each received $1,000 scholarships.

– Outstanding Paper to Gregg A. Scott and Barbara L. Mills-Bria, both with the Bureau of Reclamation. Their paper, "Nonlinear, 3-D, Dynamic, Coupled Dam-Foundation Analyses for Estimating Risks at Hungry Horse Dam," was selected based on technical content and oral presentation.

– Lifetime Achievement Award to Ralph Peck, presented posthumously. Peck, who died in March 2008 at age 95, was recognized for his achievements and expertise in geotechnical engineering. In 1948, he co-authored a book with Karl Terzaghi, Soil Mechanics in Engineering Practice, which USSD called the most influential textbook in geotechnical engineering. In 1953, Peck co-authored the widely used textbook Foundation Engineering. He was a professor of foundation engineering at the University of Illinois from 1948 to 1974. Following retirement from the university, Peck continued a consulting practice, which included jobs in 44 states and 28 countries.

Inspectors question safety of two Rio Grande dams

Technical experts who inspected four dams in the Rio Grande Basin in the U.S. and Mexico are calling for additional analyses of two of the structures they said could be unsafe.

The technical experts spent five years inspecting the four dams. They found the dams at the 132-MW Amistad and 63-MW Falcon hydro projects could be unsafe and recommended additional study.

The International Boundary Water Commission (IBWC), which is responsible for the dams, plans to use its annual allotment of dam safety program money appropriated by Congress to initiate the recommended studies, said IBWC U.S. Section spokeswoman Sally Spener.

The U.S. Section said it would work with its counterpart in Mexico to convene a joint panel of dam experts that will guide the commission in evaluating Amistad and Falcon dams. The panel could release recommendations for Amistad by fall 2008, followed by recommendations for Falcon Dam, Spener said.

A tentative schedule calls for design work in 2008 and 2009, followed by recommended repairs in 2009 and 2010, subject to appropriations, Spener said.

Amistad Dam declared potentially unsafe

Declaring the need for action at Amistad to be urgent, the inspectors classified that 254-foot-tall dam to be "potentially unsafe." The multi-purpose dam is near Del Rio, Texas, in the U.S., and Ciudad Acuna, in Mexico.

The Amistad finding was based largely on naturally occurring sinkholes that have existed since the dam was completed in 1969 and that could affect stability. The dam has a concrete gravity section and flanking earth embankments. A hydro plant was built on the U.S. side of the dam in 1983; Mexico added a powerhouse in 1987.

Falcon Dam called conditionally unsafe

The inspectors classified Falcon Dam "conditionally unsafe," saying the need for action is a high priority.

They recommended current analytical methods be used to update seepage and stability analyses of the 150-foot-tall, multi-purpose rolled earthfill embankment near Roma, Texas, in the U.S., and Nueva Ciudad Guerrero, in Mexico.

"Based on our observations, review of records, and in consideration of the project experiences with foundation seepage, sulfates in the foundation seepage, and lack of current seepage and stability analysis, we conclude that the dam is conditionally unsafe, and that specific investigations, evaluations, and studies are needed," the inspectors reported.

They said updated analyses of Falcon would help IBWC confirm, or change, classification of the dam and to make needed repairs. Power plants on the U.S. and Mexico sides of the dam each house three turbine-generators.

ASDSO offers Peer Review Program

The Association of State Dam Safety Officials (ASDSO) offers a Peer Review Program to agencies and organizations to improve dam safety programs throughout the U.S.

ASDSO says the process can validate the decisions of agencies and organizations, and point the way to improvements.

Peer Review Program committee members evaluate an agency or organization’s mission, objectives, policies, and procedures. Committee members also review the agency or organization’s program, in relation to dam safety standards. When the review is complete, the Peer Review Program team provides a confidential report of the findings to the agency engineer or director.

Peer Review Program team members are experienced dam safety professionals with at least 15 years of related experience. Most are senior members of agencies or consulting firms. The team consists of at least three reviewers, including a state dam safety official.

A review usually takes four or five days for state agencies and can last a week or more for larger programs.

Peer Review services to state agencies are included as part of the states' membership in ASDSO. Reviews of outside organizations are paid for by the organization requesting the review. Costs vary depending on size and depth of review and can be tailored to meet needs and budgets.

Since the program was created in 1990, ASDSO said it has completed more than 25 state and organization peer reviews. Four states have gone through the process twice. Several federal agencies, including the U.S. Army Corps of Engineers, and two Canadian organizations, BC Hydro and Ontario Hydro, have participated in the program.

– For information, contact: Susan Sorrell, ASDSO Peer Review Program Coordinator, (1) 859-257-5140; E-mail: sasorrell@damsafety.org.


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