Ridgefield sits on a long ridge, and up at the Ridgebury end the snow starts sooner and the wind keeps rearranging it long after the sky has cleared. Keller Construction LLC plows through those nights — driveways opened wide, walks and steps shoveled, salt and sand on the steep pitches where a car would otherwise slide back. A drift will refill a driveway twice before dawn, so the job is often not one visit but three. Coming back at first light to a property plowed down to the pavement, with the walkway already cut through, is the whole reason for the hours. They serve Ridgefield and the towns nearby.