ROCK RIVER
Retired 2020Natural Gas power plant
- Capacity
- 169 MW
- Primary fuel
- Natural Gas
- County
- Rock County
- Operator
- WISCONSIN POWER & LIGHT CO
- EIA plant ID
- 4057
- Coordinates
- 42.5820, -89.0276
ROCK RIVER, a retired 169 MW Natural Gas power plant in Rock County, Wisconsin. It was retired in 2020, according to EIA-860.
How ROCK RIVER compares
It was retired in 2020 according to EIA-860, so it is not counted in Wisconsin's operating fleet. Its operator, WISCONSIN POWER & LIGHT CO, runs 8 operating plants in Wisconsin totaling 3,001 MW. It shares Rock County with 2 other operating plants, RIVERSIDE ENERGY CENTER and AMERESCO JANESVILLE.
Grid neighborhood
The nearest named substation is NORTHWEST BELOIT (138 kV), about 4.3 miles away; the closest transmission line found within 10 miles is a 138 kV line, under 0.1 miles away. Another 7 operating power plants totaling 1,472 MW sit within 25 miles; the largest is RIVERSIDE ENERGY CENTER (696 MW, Natural Gas). Within 50 miles are 4 mapped data centers; the nearest is Network 222 in Madison, about 38.5 miles away.
Computed by Bywatts from HIFLD power plant, substation and transmission line records, EIA-860 retirement records and PeeringDB data center locations; distances are straight-line. Sources and methodology
Weather peril exposure
ROCK RIVER is a retired 169 MW natural gas power plant in Rock County, WI, formerly operated by WISCONSIN POWER & LIGHT CO. Rock County carries high modeled catastrophe exposure in the FEMA National Risk Index, scoring 4.1 of 5 at the 77th national percentile. Lightning is the leading peril, rated Relatively High by FEMA at the 97th percentile.
The Bywatts loss layer is calibrated to solar PV hardware, so it is not applied to a natural gas plant. The ratings below are the FEMA National Risk Index county hazard ratings for this location.
Rock County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Lightning | Relatively High | 97th | 4.9 of 5 | 38.5 |
| Hail | Relatively High | 81st | 4.2 of 5 | 4.3 |
| Tornado | Relatively High | 73rd | 3.9 of 5 | 0.58 |
| Riverine flooding | Relatively Moderate | 61st | 3.4 of 5 | 2.1 |
| Heat wave | Relatively Moderate | 56th | 3.3 of 5 | 3.6 |
| Strong wind | Relatively High | 50th | 3.0 of 5 | 5.5 |
| Earthquake | Very Low | 31st | 2.2 of 5 | <0.01 |
| Wildfire | Very Low | 23rd | 1.9 of 5 | <0.01 |
| Ice storm | Relatively Low | 13th | 1.5 of 5 | 0.63 |
| Winter weather | Relatively Moderate | 3rd | 1.1 of 5 | 14.1 |
| Hurricane | Very Low | 1st | 1.1 of 5 | <0.01 |
Perils not assessed in Rock County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Coastal flooding | FEMA rating is "Not Applicable" for this county |
Model hail, wind and flood exposure for Rock County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level.