39th largest plant in Washington · 1794th nationally
Mayfield is a hydroelectric power plant in Washington with a nameplate capacity of 162 MW. It generates roughly 545.0k MWh per year — enough to power about 51,905 average U.S. homes.
Its capacity factor of 38% reflects intermittent or peaking operation.
| Plant Name | Mayfield |
|---|---|
| Operator | City Of Tacoma - (Wa) |
| City | Silver Creek |
| County | Lewis County |
| State | Washington |
| ZIP | 98585 |
| Coordinates | 46.50350, -122.58850 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| 41 | Conventional Hydroelectric | Water | 40.5 MW | Operating | 1983 |
| 42 | Conventional Hydroelectric | Water | 40.5 MW | Operating | 1963 |
| 43 | Conventional Hydroelectric | Water | 40.5 MW | Operating | 1963 |
| 44 | Conventional Hydroelectric | Water | 40.5 MW | Operating | 1963 |
| NERC Region | WECC |
|---|---|
| Balancing Authority | City Of Tacoma, Department Of Public Utilities, Light Division |
Hydroelectric plants spin turbines using falling or flowing water — typically from a dam-impounded reservoir. They are dispatchable, long-lived, and emission-free at the point of generation, though large reservoirs can disrupt rivers and ecosystems and methane can be released from flooded vegetation.