Drainage, Structures, and Temporary Traffic Control
Drainage
Pipe work is accepted on bedding and haunching, backfill placed in lifts on both sides, joint tightness, invert elevation, and line and grade - check the invert with a laser or level, not by eye. Confirm that flexible pipe deflection stays within limits and that inlets, manholes, and ditch grades shed water away from the roadway. Erosion control items such as silt fence, check dams, and riprap are inspected for placement, keying, and spacing, and must be maintained, not just installed.
Structures
For foundations and piles, watch excavation limits, pile location and cutoff elevation, and driving records. Reinforcing steel is inspected for size, spacing, laps, supports, and cover before any concrete goes in. Check forms and falsework for line, grade, and stability; watch concrete placement sequence, vibration, and cold joints; verify bearings and joint devices are set to the specified temperature and elevation.
Temporary traffic control
Work zones follow MUTCD Part 6 and are built from four areas: advance warning, transition, activity area, and termination. Taper length for a lane closure uses L = W × S when the speed limit is 40 mph or less, and L = W × S² ÷ 60 when it is 45 mph or more, where W is the lane/offset width in feet and S is speed in mph. Buffer space is kept free of workers and equipment, device spacing tightens through the taper, and flaggers need sight distance and escape routes.
Worked example: a 12-ft lane closed on a 45-mph road: L = 12 × 45² ÷ 60 = 12 × 2,025 ÷ 60 = 405 ft of taper.