May is the month the valves wake up. Rivet Irrigation opens systems across Clawson as the ground warms — charging lines, setting heads, tuning spray so the water lands on turf and not on the driveway — then comes back in October to blow every line dry before the first hard freeze can find it. In between are the August weeks when the clay under these lawns bakes and cracks, and a system that runs right is the difference between green and gone. Repairs, head replacements, zone adjustments and controller settings fill the middle of the season, along with the lawn work itself. Water is the quiet ingredient under every green yard in town, and putting it exactly where it belongs is a satisfying kind of precision.