To find your water main valve, near your curb you should see a covered box labeled WATER. You can lever the top off with a screwdriver or a special “meter key” (available at local hardware stores, like Ace Hardware, Lowe’s, and Home Depot). Be very careful removing the lid as it is attached by a wire to the reading device and it is very costly to repair that connection if you break it. Go slowly.
Once you fit the meter key into the “lock,” turn it counter-clockwise, and then tilt the key toward the outer edge of the box to lift the lid open. Be careful when opening the box. Sometimes snakes, black widow and other spiders, small critters, reptiles, bugs, and other surprises are waiting for you. And, don’t forget to be careful to not break the wire connection from meter to lid.
Once you have located, opened, and cleared away any dirt or debris, it will probably look something like this: