Like most parts of the country, the Pacific Northwests power transmission system is stretched to its limits. To deal with it, the Bonneville Power Administration is planning to expand the grid by as much as 155 miles. But at the same time, it is changing its public approach to make sure that construction is the best way to go.
To smooth the contentious approval process and find cost-effective solutions to power congestion, the Portland, Ore.- based agency in early 2003 established a roundtable to examine nonconstruction alternatives. It involved potential stakeholders from the beginning. "That we are seriously considering all transmission alternatives...increases the comfort level of stakeholders," says Brian Silverstein, BPAs manager of network planning.
The 18-member roundtable includes representatives from utilities, tribes and environmental and other interest groups. It examines the feasibility of energy efficiency programs, demand-reduction initiatives, pricing strategies and distributed generation as alternatives to all new transmission lines. It also identifies circumstances in which construction is the only viable approach to meet energy needs.
"If nonconstruction alternatives are rejected because they have failed the screening criteria developed by the roundtable, then there is already buy-in for a transmission fix," says Silverstein.
The exhaustive nonconstruction analysis and consensus-building process that preceded the recently approved Kangley-Echo Lake transmission line became the model for this new approach. It may not be long, but the nine-mile, 500-kv line crosses the 90,546-acre Cedar River Municipal Watershed that supplies nearly 70% of Seattles drinking water. The $43-million line will funnel electricity to Seattle and surrounding areas.
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"Originally, the city said no, but council members were finally persuaded that the project provided enough benefits to justify moving forward," says Martin Mungia, spokesperson for the Seattle City Council.
BPA sited the line parallel to an existing right-of-way and will forgo development in the watershed. The utility also will purchase and donate 600 acres of adjacent buffer and pay the Seattle Public Utilities Water Fund $6 million.
Minimizing erosion during construction is essential. "This is an unfiltered drinking-water supply," says Lou Dreissen, BPA project manager. "Turbidity is a very big issue." BPA awarded the construction contract to Charlotte, N.C.-based Duke Energy and Blue Bell, Pa.-based Henkels & McCoy Inc. They are using helicopters instead of trucks to remove trees cut along the 100-acre right-of-way.
Subcontractors also are using helicopters to place 47 lattice-steel towers that are being assembled off site. The footing design calls for placing parts of tower legs above ground that are typically buried. The micropile footings are being placed in 6-in.-dia holes to a depth of 30 ft. They are anchored with a steel bar grouted in place.
"Normally, we do clearing, road construction, then footing in sequence, but we dont have time for that," says Dreissen. "We have 150 people working simultaneously." The project, which includes a substation upgrade, is scheduled to be in service by the end of the year.