Excavation should be carried out in a manner that avoids undue damage to the surrounding area. If, before works commencing, an undertaker feels that it is unavoidable, they should contact the authority as soon as possible to discuss the best way forward. Furthermore, if damage is caused they should inform the authority immediately so that an appropriate reinstatement method can be agreed (also see S2.8).
Trench walls should be even and vertical with no undercutting of the running surface. If undercutting occurs and compaction is impossible, measures should be taken to fill any voids as soon as practicable or immediately after trench support has been provided.
Excavations must be protected, as far as is reasonably practicable, from the ingress of water, and water running into them must be drained or pumped to an approved disposal point. Any drainage sumps must be sited to prevent damage to the excavation.