I don't know what your specific water meter box is made of but most that I ever seen are heavy plastic open framed rectangles. That is to say they are open at the top and bottom and have slots in each of the narrow ends so it will slide down over the water meter inlet line from the utility company on the street side and also on the outlet side of the meter on the home site side. This is to allow for raising or lowering the height of the box so the lid is not damaged by a lawn mower. The flip-up access door for the meter reader is flush with the top and is usually made of Cast metal. You adjust the height by adding or removing the soil below the box frame.