Familiar issues, such as underground versus overhead lines, continued to be debated in rebuttal testimony filed with the Public Service Commission of Wisconsin (PSCW) Oct. 30 in connection with the Western Milwaukee County Electric Reliability Project (Docket No. 5-CE-139).
While the proposed east-west line could be placed underground, beneath Walnut Road, an official with project partner American Transmission Company (ATC) said such an alignment would mean a significant cost increase.
“The all-underground route … works from an electrical perspective and generally addresses many of the concerns raised by a majority of the intervenors and the public,” Peter Holtz, ATC’s routing and siting manager, said. “However, there are a number of significant constructability challenges [that] significantly increase the cost of this option. The estimated cost to construct this route, with one cable per phase, is $30.3m.”
Holtz continued, “While constructible, ATC believes the cost and engineering challenges of that route (particularly in the area of the Hwy 100/Watertown Plank Road intersection where the presence of two rail lines, Underwood Creek, a recreation trail, and extensive existing utility infrastructure below ground) make it non-competitively expensive.”
By contrast, the “hybrid” modification to the Wauwatosa all-underground proposal for the east-west line would reduce the estimated cost by $8.75m compared to an all-underground route, he said.
The proposed north-south line was also a topic of discussion.
The head of the Milwaukee Montessori School, Monica Van Aken, filed testimony in support of a combination routing that would place the line underground, along an easement offered to ATC by the school and St. Therese’s Church. Van Aken said that alignment “would result in a cost savings of approximately $2.5M.”
ATC’s expert disagreed, and said the alternative was not technically viable.
“ATC evaluated the proposal in cooperation with We Energies’ (WE) distribution planning engineers and the lead designer for the [Wisconsin Department of Transportation] zoo interchange project,” Holtz said. “[T]hese parties determined that, using standard conductor sizes and construction techniques, there was not sufficient room to locate the project underground along with the existing distribution circuits that are west of the apartment building. Based on this analysis, this proposal is not feasible.”
Van Aken also criticized ATC for not being sufficiently responsive to its concerns about an overhead alignment.
“ATC has not acknowledged our concerns regarding the viability of the school nor conducted a sufficient and accurate analysis of the economic consequences of their proposed route alternatives,” Van Aken said.
“Had ATC evaluated the cumulative and synergistic effects of the overhead lines in the vicinity of the school, ATC would have come to far different conclusions in the analysis of alternatives and a far more accurate evaluation of the hardship impacts on the school, the church and the Cannon Park neighborhood community,” she continued.
ATC’s expert, however, disputed the prediction of purported financial consequences for the school and church if the line was built overhead, and cited other instances in which overhead lines had not proven to be detrimental.
“We have not seen the dire financial consequences forecast by the witnesses for the Milwaukee Montessori School, (MMS)” Holtz said. “For example, Pius High School, located … approximately one mile to the east of MMS, has a double circuit 138-kV line located approximately 100 feet from the school building. St Thomas Aquinas Academy … in Milwaukee is approximately 175 feet away from a 138-kV overhead line.”
He said: “There are a number of public and private schools in ATC’s service area which [are] located within 200-250 feet of overhead transmission lines. None of these institutions have indicated to ATC that there is a negative impact – financial or otherwise – from the presence of the overhead transmission facilities.”
Although ATC said the revised underground proposal presented by the school was not feasible, Holtz did not categorically rule out all underground route alignments.
“ATC has reviewed the underground proposals provided by a number of parties and has identified some as constructible and as meeting the reliability criteria of the Level 1 Trauma Center Planning Guide,” he said, referring to the reliability needs of the Milwaukee Regional Medical Center, which the new lines will serve.
He also restated the additional expense of undergrounding the proposed lines.
“While these underground alternatives are generally two to three times more expensive [than] the overhead options, they avoid certain impacts of overhead lines,” he said. “Whether those benefits are worth the extra cost is essentially a value judgment that also implicates issues of fairness to all ratepayers across the ATC system.”
Projected cost data submitted in rebuttal testimony revealed a cost range of the ATC-proposed alignments that range from $17.8m to $35m for the transmission lines. The new substation that is part of the project will add an additional $5.5m to the total cost.
ATC also estimated the cost of the alternative routes suggested by other parties.
“The total transmission line costs, using either of the Wauwatosa routes starting at Walnut Road combined with either an overhead or underground route from the south, result in a range of transmission line (only) costs from approximately $26.4m to $50.8m” for the project, according to Holtz’s testimony.
Hearings before the PSCW are scheduled for Nov. 27 and 28. Regulators are expected to decide early next year whether the lines are needed. The PSCW would then select routes for the two lines and decide whether they should be built underground.
The PSCW will determine the final routes for the two lines. We Energies will build the necessary substation facilities, while ATC will build the transmission lines. The project is planned to be in service by March 2015.
We Energies is a subsidiary of Wisconsin Energy (NYSE:WEC).