Study Team: Northern Mid C Study Team

Northern Mid C Study Team Overview

The 2008 System Assessment found deficiencies in the Northern Mid-Columbia transmission system. The transmission system that delivers generation from Wells, Rocky Reach, and Rock Island dams is primarily 230-kV, with an underlying 115-kV system that provides load service. Contingencies that disrupt the 230-kV system at either Rocky Reach or Columbia substation, or the 115-kV system at Valhalla, McKenzie, or Columbia substations result in overloads. The underlying causes of these problems are a combination of load growth and the wide range of possible generation patterns. ColumbiaGrid has formed the Northern Mid-C Study Team to resolve these transmission issues.

A report was completed and the impacted utilities agreed on cost allocation of preferred plans. The plans are now being implemented.



Status: Complete

Lead Staff:
Larry Furumasu   Contact

03/09/2021 N. Mid C Outage Results Final (v: 1)   

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02/25/2010 N. Mid C Outage Summary Tables (Final) (v: 1)   

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02/23/2010 North Mid-Columbia Study Report (Final) (v: 14)   

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06/23/2009 North Mid C Summer 2019 Base Case (v: 4)   

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05/14/2009 North Mid C Winter 2019 Base Case (v: 1)   

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