Trenching A specific type of narrow, deep excavation performed to install underground utilities, conduits, or drainage systems.
Whenever a property owner needs to install new plumbing, electrical lines, or drainage systems, trenching must be performed beneath the sidewalk area. In NYC, any trenching in the public right-of-way requires utility markouts via "811 Call Before You Dig" and specialized DOT permits. Once the utility work is complete, the trench must be backfilled and compacted perfectly to prevent the sidewalk above from settling.
Frequently Asked Questions About Trenching
What is trenching?
A narrow, deep excavation used to install underground utilities, conduits or drainage.
What is required before trenching in the right-of-way?
Utility markout through New York 811 and the applicable DOT permits.
Why does backfill compaction matter so much?
Poorly compacted backfill settles over the following months, dropping the sidewalk above and creating a defect.
Who restores the sidewalk after trenching?
The party that performed the work is generally responsible for restoring the surface to specification.