Water on the corridor floor. A dozen lines overhead. Which one?

It's locating the source of water inside a utility tunnel or service corridor — the walk-through or crawl-through galleries that carry a building's or campus's services (domestic water, heating and chilled loops, steam and condensate, fire lines, sometimes electrical and comms) packed close together. Water appearing in a corridor could come from any of those lines, from condensate, or from groundwater infiltrating the structure itself — and telling them apart is the whole job, because each source sends a completely different repair.

Because everything is in one place and water travels. A drip on the floor of a tunnel may originate from a chilled-water line ten metres back that's been running condensate along a cable tray, from a pinhole in a heating main overhead, or from groundwater entering a wall joint. Lines run parallel and close, labels are often gone, and shutting the wrong one wastes an outage. Methodical discrimination — chlorine and temperature testing, acoustic and thermal work, line isolation — is what separates the actual source from its neighbours.

Yes, and it's one of the most valuable distinctions we draw. Treated system water tests positive for chlorine and tracks system pressure and usage; groundwater follows rain and the water table and enters at structural joints. Temperature, flow pattern, and acoustic checks confirm it. Getting this right means you either fix a pipe or address waterproofing and drainage — never both blindly, and never the wrong one.

Usually not for the investigation — acoustic, thermal, and discrimination work happen on the live, operating services, and access follows the facility's confined-space and safety procedures for the corridor. Isolation of a specific line is only used to confirm a suspected source, planned with your operations team around redundancy. The aim is to find the source without the broad shutdown a blind search would force.

Universities and colleges, hospitals and health campuses, large institutional and government complexes, airports, and older downtown districts with shared service tunnels. Anywhere a central plant distributes services to multiple buildings through accessible galleries rather than direct burial — exactly the settings where a corridor leak is both common and consequential.

A documented source determination: which line or which structural path is leaking, where, with the evidence (chlorine results, thermal imagery, acoustic findings) and a clear repair scope handed to the right trade. For institutional and public-sector facilities that report integrates into facility-condition records and procurement processes — see our leak detection reports service for the documentation framework.