Reference

KZZO, a radio station based in Sacramento, has a notably high Effective Radiated Power (ERP) of 115,000 watts. This allows the station to cover a larger geographical area compared to other FM stations in the region. The reason for this higher ERP is historical; KZZO is "grandfathered" at this higher power level. This grandfathering means that KZZO was allowed to maintain its higher power output from before newer regulations were put into place, which now typically cap the power levels for most FM stations to lower limits.

For more detailed historical information, you can refer to the KZZO Wikipedia page.