Site Utilities
CSI Division 33, Utilities
The underground water, sewer, storm drainage, electrical, and gas infrastructure installed to connect a building to the municipal or utility systems it depends on, coordinated across multiple utility trades and typically installed before paving locks the site's final surface into place.
Why it matters
Site utility work happens underground and gets buried almost immediately, so coordination between the different utility trades has to happen on paper before digging starts: discovering a conflict between a sewer line and an electrical duct bank after one of them is already installed means excavating back into ground that's already been backfilled.
On a real project
A project's civil engineer produces a utility coordination drawing showing every underground utility's planned location before any excavation begins, letting each utility trade verify their work won't physically conflict with another trade's buried infrastructure.
Who this matters most to
An Equipment Operator excavates and backfills for each utility trench to the coordinated utility plan. A Project Engineer tracks the different utility subcontractors' installation sequencing, since site utilities often involve more separate trades working in the same confined area than almost any other project phase.
Where this goes wrong
A sewer line is installed at the depth shown on its own trade's drawing without cross-checking a nearby electrical duct bank's drawing, and the two are installed at crossing elevations that violate the required separation between utilities. The conflict isn't discovered until an as-built survey catches it, requiring one of the already-backfilled utilities to be re-excavated and re-routed.