The City of San Diego allows contractors to use steel trench plates on trench projects. Following is the language from city Standard Specifications for Public Works Construction:
“Trenches shall be backfilled or trench-plated at the end of each work day. An asphalt ramp shall be placed around each trench plate to prevent the plate from being dislodged.”
Also see 7-10.6 Traffic Plate Bridging in Standard Specifications for additional requirements for the use of trench plates.