On October 17, 1989, a 6.9 magnitude earthquake struck the Bay Area at 5:04 p.m. The rupture was related to the San Andreas fault system and effected all Bay Area counties with a maximum Mercalli intensity of IX ("Violent"). Many structures in Oakland were badly damaged including the double-decker Cypress Street Viaduct in West Oakland that collapsed. The eastern span of the San Francisco–Oakland Bay Bridge also sustained damage and was closed to traffic for one month; the bridge reopened on November 18. Oakland became the home of the emerging nonprofit preparedness movement in the aftermath of the earthquake when local agencies formed CARD (Collaborating Agencies Responding to Disasters) to address the unmet emergency readiness needs of the nonprofit and faith sectors.