The City of Hayward Police Detention Facility is located at Hayward Police Building
300 West Winton Ave, call 510-293-7017, 510-293-7000 to find out about new arrests or outstanding warrants. This is a police jail for housing inmates immediately after their arrest. Local police departments are not built for long-term inmate holding, they are for very short-term stays because there are not enough cells. There are no visits, commissary or phone accounts available to the offenders.
If they are to remain incarcerated, it will be most likely to the Alameda County Sheriff's nearby facility.