Cost To Bury Power Lines In Heber Valley Is Four Times The Price Of Overhead Project

Jul 26, 2018

Credit Wasatch County

Rocky Mountain Power Company and the municipal power company, Heber Light and Power, are evaluating the feasibility of burying new high power lines through the Heber Valley. The community has expressed opposition to the original plan which would run the 100 foot power poles through sensitive view corridors. Rocky Mountain Power would pay for the costs of installing above ground lines but the Heber Valley Community would have to pay for the difference in costs to bury them.   Carolyn Murray has this:

The spokesperson for Rocky Mountain Power, Dave Eskelsen, says the original intention for installing the new transmission lines is being reconsidered by officials.

“We’re working with Heber Valley Light and Power. They’re the lead project manager of that because they need a new delivery point in the Heber Valley. We’ve faced some significant questions about whether that’s really needed. We’re working with elected officials there on some alternative proposals. They wanted some estimates of underground costs. So we’re just working through the process there.”

Eskelsen says there are just two supply lines into the Heber Valley and that’s not enough to insure service to the area if one line goes down.

“Well it’s mostly about what the Heber Valley community needs. Right now there are two feeds into Rocky Mountain Power Customers in the Heber Valley. Also, that includes Heber Valley Light and Power. If either one of those supply lines goes down for any reason, the one alone is not sufficient to supply the entire valley. That’s a particular concern in the winter months.”

Eskelsen says Rocky Mountain Power needs to complete the supply loop to serve their customers on the Wasatch Front in the event that one of the two current power lines is compromised.

“Heber’s needs are a little different.  They need another delivery point for transmission to serve their customers.  Until those additions are in place, that area does not have the same kind of reliability that most of our customers enjoy.”

Power interruption from wind, storms and fires can disrupt above ground power lines but overall, Eskelsen says,the service is not necessarily better when lines are buried.

“Underground service presents its own reliability issues for transmission.  If you bury transmission, it’s a vital enough concern that you have to make it redundant which greatly amplifies the costs and also with underground service, when something does go wrong, it usually takes much longer to fix. That’s why most transmission of the voltage we are talking about is constructed overhead.”

The Heber Light and Power Board continues to work with Rocky Mountain Power to look for transmission and reliability solutions for the region overall. Over-head power lines cost about $1.2 million a mile. Buried power lines cost up to 4.5 million per mile.