Fire flow, not building area, sizes the water line serving an industrial building. A warehouse with high-piled storage can demand sprinkler flow and hose-stream allowance that exceed what a standard municipal service can deliver, and the answer shows up as a larger main, a looped system, an on-site tank and pump, or all three. We build fire water systems on industrial sites, and we start by asking what you will store, how high, and in what packaging.
The usual package includes a fire service line from the main, a looped private main around the building where the fire district requires it, post indicator and sectional valves, hydrants spaced to the fire code and the district's access rules, backflow prevention, fire department connections, and the riser room tie-in. For larger demand we add a fire pump house, jockey pump and water storage tank, often with the electrical and controls scope carried by the same team.
Because the fire district reviews and accepts the work, we treat it as a regulated scope with its own schedule. Material submittals for pipe, fittings and hydrants, the flow test of the municipal main, the underground inspection before backfill, the hydrostatic test, and final flushing are scheduled as milestones. Missing any one of them delays the certificate of occupancy for a building that is otherwise finished.
Fire codes are local too
Fire codes in Colorado are adopted by cities, counties and, in many places, individual fire districts. Denver adopted new building and fire codes on June 13, 2025, based on the 2024 International Building Code, with a transition period of about six months. In Eagle County, the Building Resolution amended January 21, 2025 adopts the 2021 International Building Code with fire codes amended and adopted by Vail Fire and Emergency Services and other fire districts. The authority that signs off on your hydrants can be different from the one that signs off on your building.
We therefore meet the fire marshal during design. Hydrant spacing, distance from the building, required flow, apparatus access width and turning radius, gate and key-box requirements and fire lane marking are confirmed in writing. In mountain communities near Vail and Eagle County and Summit County, the wildfire provisions add another layer, which we cover in the site plan.
Demand, supply and the flow test
The flow test of the nearest main tells us what pressure and volume the municipal system can supply. We schedule it early because water providers often need advance notice, and a test run in the wrong season or at the wrong time of day can give a misleading result. The result then drives the decision between a direct connection, a larger extension, a looped main, or a tank and pump.
Hazard class and storage matter. A warehouse building storing plastics at rack heights above the base design needs a more demanding sprinkler system than the same building storing steel parts. A plant with a hazard such as a process fuel supply, for example near the kind of refining and fuel handling that the 98,000 barrel-per-day Suncor refinery in Commerce City represents, has to consider adjacent exposure in the site plan. We make sure the sprinkler contractor, the engineer of record and the fire marshal agree on the basis before we size the underground.
Building the underground
Fire mains are ductile iron or PVC, installed to the standards of the water provider and the fire code, with restrained joints, thrust blocks, tracer wire and depth of bury that matches the local frost depth. Mains are bedded, joints are inspected, and the line is hydrostatically tested at the pressure and duration required before backfill is completed and before connection to the building riser.
Hydrants are set at the correct elevation relative to finished grade, with a gravel sump, restraint, bollards where exposed to traffic and a protected valve box. Post indicator valves and control valves are placed where the fire department can reach them and where trucks cannot strike them. The site utilities package trade crew builds the fire line in the same trench plan as water, sanitary and storm, and the crossing elevations are drawn before excavation.
Sequence and lead times
Underground fire lines are installed before the slab, since riser penetrations and thrust blocks are tied to the foundation. Pump house equipment, tanks and controls can take a long time to deliver, and they appear in the long-lead procurement register. Acceptance testing needs the system to be clean and charged, so site cleanup and permanent water have to be available in time.
The schedule for the final acceptance should be set with the fire marshal weeks ahead. In many offices, the fire inspector's calendar is the pacing item. We invite the sprinkler contractor and the alarm contractor to the walk so the tests are completed in one visit and not three.
Where it fits with the rest of the project
Fire water ties into the overall utility plan, the commissioning and turnover process, and the layout of yards and aprons. Hydrants and fire lanes occupy space in a truck court, so we coordinate them with traffic and trailer positions to keep fire access clear at all times.
For owners in logistics and distribution, where the storage is dense and the building is large, getting the fire water right at the start avoids redesign when the sprinkler design is finalized. Owners with process or hazardous areas can expect additional design review, and we plan for it from the beginning.
Test the water before you design the building
Send us the parcel and the storage plan. We will arrange the flow test and size the fire water system with your engineer.
Common Questions
How do I know if I need a fire pump and tank?
The flow test and the sprinkler demand answer that. If the municipal main cannot supply the required flow and pressure at the building, you need a pump, a tank, or a larger main. We compare the cost of each so you can choose.
Who owns and maintains the private fire main?
Usually the property owner. Municipal systems end at the connection point, and the private main is the owner's responsibility for inspection, testing and repair. We provide as-built drawings and a record of tests so maintenance is straightforward.
What are the acceptance tests?
Typically a flush of the line, a hydrostatic test at the specified pressure and duration, and a flow test of the hydrants and the sprinkler system. The fire district may witness. We prepare the paperwork and keep it with the turnover package.
Do wildfire rules affect industrial sites?
In some mountain jurisdictions, yes. Summit County, for example, rates all of the county as moderate to high fire intensity and requires Class 2 structure hardening under the Colorado Wildfire Resiliency Code with county amendments for permits applied for after May 4, 2026. We check the rules for each location.