On Tuesday, the board directed staff to seek funding for the county-operated alert system that would allow residents to sign up to be notified by e-mail when a registered sex offender moves into their area.
Supervisor Bill Horn brought the proposal to the board, saying the county needs new ways to protect children from sexual predators.
San Diego has to "explore new ways to protect our children from sexual predators," Horn said.
Horn also said the current information available online is out of date.
The move by the board of supervisors came in the wake of the disclosure on Monday that investigators did not know to check in with registered sex-offender John Gardner, who was living with his mother near the spot slain Poway student Chelsea King was last seen but had not registered at that new address.