Originally established as the Riverside County Office of Disaster Preparedness (ODP) in 1971 through County Ordinance 533.4, the organization and role of this function has evolved to meet an every increasing demand for emergency and disaster management activities. The functions and organization of (OPD) were transferred to the Riverside County Fire Department in 1984 and became known as the Emergency Services Division or ESD. In following suit with other County Emergency Management organizations and the Governor's Office of Emergency Services, the Emergency Services Division (ESD) was renamed the Office of Emergency Services in the Spring of 2002.

Today, OES maintains two active Emergency Operations Centers (EOC's) and employees a staff of twelve people who collectively cover two EOC's, all field activities and related administrative responsibilties in one of the fastest growing county's in the nation.