Just cuz energy and hydro has long been a thing for me, I gotta' correct Todd. Seattle gets about half its electric energy from 5 dams in owns and operates, 3 on the upper Skagit River, one on Newhalem Creek, and one at Boundary on the Pend Oreille River. The other half comes from a combination of BPA and other utility contracts and the energy spot market.
Puget Sound Energy generates only a small amount of the power it sells. The Baker dams, Snoqualmie Falls, and Electron (which it sold to another private company about 5 years ago) provide a small fraction of PSE's energy. A lot comes from long term sales contracts with Chelan, Douglas, and Grant PUD dams on the mid-Columbia. It's worth noting that those 3 counties couldn't secure financing on their own to build their 5 mid-C dams. It was the long-term energy sales contracts with PSE (its predecessor actually) that swung the deal to finance those big dams.
The next 2 dams on the Columbia, Chief Joseph and Grand Coulee, are major socialist projects, built and operated by the Bureau of Reclamation, whose associated irrigation projects makes much of eastern WA inhabitable and economically productive. Absent the socialism, most of that area would remain an unproductive dustbowl.
Yea socialism! Right?