Columbia, Missouri transmission project poised to advance

Officials at Columbia (Mo.) Water and Light are optimistic that a 13-mile transmission project identified as needed six years ago will be able to move forward after a public hearing in July gives area residents the opportunity to comment on two alternatives to the utility’s original plan to beef up the area’s transmission system.

The Southern Columbia electric transmission line project has been in the planning stages since 2007 when the utility’s annual reliability assessment identified the need for a new substation and transmission lines to accommodate growth in the southern portion of the city and to meet NERC standards.

“We need to build some redundancy, and we also have increased electric load in the southern part of town, so we need additional transmission lines,” a utility spokesperson told TransmissionHub June 14.

To meet those needs, the utility proposed constructing new 161-kV transmission lines to connect the existing Perche, McBaine and Grindstone substations with the proposed Millcreek substation. The three existing substations form a triangle, and the new substation will be located in the middle. However, after three open houses in 2010 resulted in complaints about the proposal from members of the public, the city council in early 2011 directed the municipal utility to come up with additional options.

Utility officials developed two options to augment their original proposal, which is now identified as Option A. Option B consists of a 161-kV segment that will connect the Perche substation to the McBaine substation, and a 69-kV transmission line to connect the Millcreek and Grindstone substations. Option B-2, a variation on Option B, would connect the same substations with lines of the same voltages as Option B, but would extend the route of the 161-kV line farther to the west to use city-owned property for a portion of the right-of-way (ROW).

Utility representatives met with city council members in a work session on June 13, during which they recommended the council approve the utility’s original alignment. Option A, the utility said, is the most cost-effective and the option that offers the longest-term solution to the city’s power issues.

Option A was also the alignment preferred when the utility surveyed its customers. When asked, 76% expressed a preference for implementing Option A. Option B was favored by 17% of respondents, while 7% favored Option B-2. As to their willingness to pay more for undergrounding, 53% of respondents said it would be acceptable to raise rates for burying the lines, while 47% said it was not acceptable. Approximately 1,600 customers responded to the survey.

After hearing from the public next month, the city council will render a decision on the two facets of the project.

“The council will decide on which route they want us to build, and whether they want it all overhead, all underground, or a combination of the two,” the spokesperson said. “From there, we’ll actually be able to go into the final design phase.”

The utility hopes to have a decision in August.

The council’s decisions will determine the direction of the project’s design phase, and will also help the utility determine a more accurate cost estimate for the project, which currently covers a fairly broad range.

“Our estimated construction cost for overhead lines ranges from $10m to $13m, and underground ranges from $76m to $98m,” the spokesperson said, noting that the figures do not include any costs for obtaining the necessary easements.

The utility hopes to have the project completed and energized by June 2017.