Trench Excavation and Backfilling

water pipe was being installed in a southern community next to an existing main. A trench was dug with steeply sloping sides, but little bracing was used, for the soil appeared to be quite stable. During the pipelaying, however, the trench caved in and trapped several workmen. Although the men were not killed by the cave-in itself, the old water main burst and they were drowned in the rising water. This is not an isolated case. The