Worked Example: The First Hour at a Burst Water Main

Burst water main traffic control in the first hour is about speed without shortcuts: get the right crew and gear moving, assess from a safe spot on arrival, keep everyone off a road that may be undermined, set up a layout prepared by a qualified person that fits the site, and escalate early. Record from the first call.

This is an example scenario, minute by minute. It is not a real utility, company or incident. It is written for allocators, supervisors and controllers who take emergency call-outs, and for utility staff who engage them. It is not legal or engineering advice: layouts must be prepared by a suitably qualified person, and state and road authority emergency procedures apply. For the broader picture, see our guide to traffic management for emergency repairs and burst water mains.

The example call-out

Example scenario: at 6:05 am on a weekday, the allocator at a traffic control company takes a call from a water utility's dispatcher.

• Location: a two-lane-each-way collector road, posted 60 km/h, near a set of shops and a bus stop.
• What's happening: a main has burst under the kerbside lane of one direction. Water is flowing across both lanes in that direction and into the gutters. The utility's crew is on the way; police are not on scene.
• Timing: the morning peak starts building from about 7 am.
• Request: a traffic control crew to make the site safe and manage traffic while the utility isolates the main and assesses the damage.

Minutes 0 to 10: the allocator's questions

The first 10 minutes decide the next 50. The allocator works through a short script and writes down the answers.

Then the allocator picks the crew: the nearest available supervisor with the implementation ticket and a fully stocked ute, plus a second controller. The allocator checks both have had their rest since their last shift, because emergency call-outs are exactly when fatigue gets ignored. A second ute with extra signs and barriers is sent as backup. The crew gets the address, the utility contact and the job number by text. Our guide to emergency traffic control covers how companies staff these calls.

Minutes 10 to 30: the drive and the arrival check

On the way, the supervisor thinks through the likely layout: a kerbside lane closure in one direction, possibly both lanes in that direction if water is across them, using the company's pre-approved emergency layout for this road type if it fits.

On arrival at 6:28 am, the supervisor does not drive into the water. They park upstream, off the travel lane with beacons on, and assess from a safe position.

Arrival checklist:

• Where is the water coming from, and how far has it spread?
• Is the road surface intact? Look for cracks, a dip, lifted asphalt or water bubbling up through the surface.
• Is anyone or anything at risk right now: pedestrians at the bus stop, cars driving through, the utility crew?
• Which lanes need to close to keep traffic away from the affected area with a margin?
• Does the pre-approved layout fit this site, including side streets, driveways and the bus stop?
• Are there overhead lines, open pits or other hazards?

In the example, water is flowing across both lanes in one direction, and there is a visible dip in the kerbside lane where it is coming up. The supervisor decides both lanes in that direction need to close. The road is undivided, and the company's pre-approved layout for this road type covers that case: it closes the affected direction's lanes and keeps one lane each way on the other side of the centreline, with signs and a reduced speed as the drawing shows.

Minutes 30 to 45: making it safe

Set-up follows the order drivers meet devices, starting upstream in the affected direction.

1. Advance warning signs, including a reduced speed if the layout includes one.
2. Lane closure signs and the taper, as the layout shows, keeping well back from the water and the dip.
3. Delineation around the affected area, with a margin beyond the visible damage.
4. Opposite direction signs as the layout shows, warning of the changed lane arrangement.
5. Pedestrians: the footpath next to the burst closed and pedestrians directed to the other side, because water and a possible void are next to the kerb.
6. Bus stop: closed and signed, and the utility asked to notify the bus operator.

What goes wrong in the example:

6:35 am. A driver goes through the water. Before the taper is complete, a car drives through the affected lane at speed, spraying water onto the footpath. The second controller holds traffic briefly with the layout's controls until the taper is in. Nobody is hurt.

6:42 am. The dip grows. The utility crew arrives, looks at the dip and says the surface may be undermined further than it looks. The supervisor extends the delineation to keep traffic, crew vehicles and people further from it. The utility's vehicles are parked upstream, not on the affected surface.

6:50 am. The layout doesn't fit one detail. A side street enters within the closure area, which the pre-approved layout does not show. The supervisor does not invent a new layout. They place the controller at the side street to manage turning traffic as a temporary measure, and phone the company's traffic designer for advice and a site-specific TGS. Our guide to standard TGS templates explains when a standard layout can and cannot be used.

Minutes 45 to 60: escalation and handover

By 6:50 am the immediate area is safe. The next 10 minutes set up the rest of the job.

• Road authority. The utility notifies the road authority as its emergency process requires. In NSW, which authority depends on whether it is a state or council road; check the current process with the authority. The supervisor confirms the notification has been made and records who made it.
• Duration. The utility estimates the repair will take most of the day. That means the morning peak will hit the closure, queues will grow, and the job needs a site-specific TGS and probably more controllers.
• More crew. The supervisor calls the allocator for a relief controller and a third person for the peak, with the backup ute's barriers.
• Queue watch. The second controller watches the back of the queue in the affected direction. If it reaches back to the intersection upstream, they call it in.
• First formal inspection. At 6:58 am the supervisor records the first inspection: devices, signs, the extent of the closure and photos from each approach and of the damage.

At 7:05 am, the designer emails a site-specific TGS that includes the side street. The supervisor checks it against what is on the road, makes the changes it shows, and briefs the crew and the utility's foreman. The SWMS is signed on by everyone on site, including the backup crew as they arrive.

The first-hour timeline at a glance

Common first-hour mistakes

• Driving into the water to get a closer look. The road may collapse under the ute.
• Coning around the visible water only. The damage underneath can be wider than the water.
• Using a layout that doesn't fit and not saying so. Get advice and a site-specific TGS.
• Leaving pedestrians next to the burst. Close the footpath beside it.
• No record until things calm down. By then the times are guesses.
• Ignoring fatigue because it's an emergency. Check rest before sending people.

For the WHS framework, check SafeWork NSW and Safe Work Australia; for NSW road requirements, Transport for NSW. Our guide to utility works traffic management covers planned work by water, gas and power crews.

Next steps

Write an allocator's call-out script, keep pre-approved emergency layouts in every ute, and start the record at the first call. Operators can see today's shifts on a live operations view and send emergency shift offers to available crew through TrafWise.