The Electrical System

The electrical power system is divided into generation, transmission and distribution. This system allows the PUD to provide safe, reliable and clean energy to more than 47,000 customer-owners.

Graphic of the steps in electrical power delivery
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In Chelan County, electrical power is generated at one of the PUD’s three hydroelectric projects: Rocky Reach Dam, Rock Island Dam, and Lake Chelan Dam.


The power generated at the hydroelectric projects moves at a high voltage to a transmission switchyard, where electrical voltage is reduced by transformers. The power then travels along smaller transmission lines to distribution substations throughout the County.


When the high voltage electricity reaches the substations, it is transformed down to a lower voltage appropriate for distribution. Finally, power travels along distribution lines that may be overhead or underground. It reaches smaller transformer, where it is converted to a standard voltage for use in a customer’s residence or business. 

Maintaining the Electrical System

The PUD regularly performs upgrades and maintenance on the power system to maintain reliable electrical service for our customer-owners. Visit our In Your Neighborhood page for more information about our current projects!

Image of power line with line crew making repairs
Line crews make repairs to a distribution line
Aerial photo of Rocky Reach Dam
Rocky Reach Dam on the Columbia River