Most likely your water delivery agency will require you to choose from lists of approved plants. I don't imagine most veggie and fruit trees would fit the low water use requirements, though there might be some exceptions. From the SB WATER website : "approved irrigation equipment and landscape materials (but not landscaper labor costs)" They also require a minimum of 3" of mulch.
If you are planning on relandscaping with water wise plants, it's sure worth checking out. But ASK the agency FIRST what is required. Keep your receipts.