ISJ Underground Utilities LLC delivers expert underground infrastructure — water mains, sewer systems, lift stations, and fire line services — for commercial and municipal projects across the Greater Houston area.
ISJ Underground Utilities LLC is a Houston-based general contractor specializing in the construction and installation of underground utility infrastructure. From domestic water lines to complex lift stations and force mains, we bring the experience, equipment, and dedication required to deliver every project safely and on schedule.
As a certified Disadvantaged, Minority, Small, and Women's Business Enterprise, we partner with municipalities, developers, and general contractors to build the systems communities depend on — the ones you never see, but always rely on.
We self-perform a complete range of underground utility and site infrastructure work, handling each project from excavation through final connection and testing.
Installation of domestic water line mains and service connections that deliver safe, reliable potable water to your development.
Precision installation of sanitary sewer collection systems engineered for proper grade, flow, and long-term performance.
Storm sewer drainage systems that protect sites and roadways from flooding through properly engineered conveyance.
Design-build support and installation of wastewater lift stations and pressurized force mains for challenging terrain.
Storm sewer detention systems that manage runoff and meet stringent municipal stormwater requirements.
Complete fire line packages — TS&V, fire line risers, FDC connections, and full system installation to code.
Hand tunneling for crossings and tight-access work where open cut isn't an option — precise, controlled, and minimally disruptive.
Water storage tank installation and site piping — foundations through final connection and testing.
Fire pump house construction and equipment installation — pumps, piping, and controls built to fire code.
Standby and backup generator installation for lift stations, pump houses, and critical site infrastructure.
Dry bore and trenchless crossings under roads, highways, and utilities — up to 36" and beyond.
An experienced team of project managers, estimators, and administrators dedicated to delivering your underground utility project on time and on budget.
A look at our underground utility work across Texas — organized by project. Tap any photo to view it larger.
ISJ Underground Utilities is part of the multi-year effort bringing municipal water and sewer service to the historic community of Tamina, north of Houston.
Launched in 2023, the project will allow the City of Shenandoah to deliver water and sewer service to property owners and businesses across the community — work that's now entering its final phase.
Follow ISJ Underground Utilities on LinkedIn for project updates, jobsite photos, and news from the field.
Reach out for estimates, bid invitations, or to learn more about our underground utility services. We respond promptly to every inquiry.
We partner with the engineering firms shaping Houston's infrastructure.
