Howdy! I'm in San Diego, about 8 miles inland from Del Mar.
About your front lawn ... look at it this way: 1 lawn sprinkler emits at least 3 gallons per minute of water. For every lawn sprinkler head, you could have 1 fruiting tree or 2 fruiting vines/shrubs instead.
My "front lawn" is a 4 x 10 foot walkway from the front door to the right side gate. It's in the shade a lot, so 2 sprinklers water it twice per week. I have a modest back yard lawn for pets and kids ... the rest is fruiting and flowering plants!
Here is what you could achieve, bit by bit over 7 years:
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