If you have lost your card, notify the library immediately with your name and address or card number. We'll place a "block" on your account so no one can borrow without presenting valid picture ID.
You can replace the missing card on your next visit to your Community Library. Bring your valid picture ID. Replacement cards are free.
In the meantime, if you are a Contra Costa County resident you can apply online for an e-Card, which allows you to use databases and to place holds until you are able to replace your full-service library card.