Worked Example: Running Stop/Slow on a Two-Lane Rural Road With a Crest

On any stop slow rural road job with a crest, one question decides the layout: can every approaching driver see the controller, or the back of the queue, in time to stop? Place stations and advance warning exactly as the TGS shows, test sight lines and radios on site, and keep the queue short of the crest.

This is an example scenario walked through from the night before to pack-down. It is not a real job, client or incident. It is written for supervisors and controllers who already hold the right cards, and it does not replace accredited training, the approved traffic guidance scheme (TGS) or your state's manual. The TGS must be prepared by a suitably qualified person. If you need the basics first, start with our guide to stop/slow traffic control.

The example site: culvert repair below a crest

Example scenario: a council maintenance crew needs to replace a collapsed culvert headwall on the shoulder and part of the northbound lane of a two-lane rural road.

• Road: one lane each way, sealed, posted 100 km/h, gravel shoulders, farm gates on both sides.
• Geometry: a crest about 250 metres south of the work site. Northbound drivers come over the top and descend towards the work.
• Work area: half the northbound lane plus the shoulder, so one lane must carry both directions.
• Plant: a small excavator and a tipper, with occasional truck movements in and out.
• Traffic: light, with farm vehicles, school buses at set times and some heavy vehicles.
• Hours: 7 am to 4 pm, one day.
• Crew: a supervisor with the implementation ticket, TC 1 at the north station, TC 2 at the south station, and a ute at each end.

The TGS provides for stop/slow with a reduced speed zone on both approaches, advance warning set back for the approach speed, and a note that the south station must be visible to northbound drivers before they reach it. The client considered portable traffic lights, but site access and the one-day duration led the designer to manual control with a reduced speed. That choice belongs to the TGS, not the crew.

The night before: reading the TGS against the road

A good supervisor does the first check from the depot. Using the TGS and a street-level map, they ask:

• Where exactly is the south station relative to the crest? The TGS puts it well down the descent, with the PREPARE TO STOP sign placed so drivers see it before the station.
• Where will the end of the queue sit if traffic is held? This is the question that matters most on a crest.
• Are there farm gates or side tracks inside the shuttle lane? Two farm gates are on the work side.
• Where is the nearest point for a U-turn if a heavy vehicle needs to be redirected?

Then the queue maths. This is an example calculation with assumed numbers, not a rule.

On those numbers the queue stays well short of the crest. But a school bus run plus a few trucks or a longer hold during a tipper movement could double it. The supervisor notes a trigger: if the northbound queue reaches the PREPARE TO STOP sign, shorten holds and call it in. Our free stop/slow cycle planner and the guide to stop/slow cycle time calculation show how to do this properly with your own counts.

Morning set-up: order, sight lines and radios

Arriving at 6:15 am, the supervisor runs the pre-start with the council crew: the TGS, the shuttle lane, who can enter it, escape routes for each station, where the tipper turns, the radio channel and backup, the fallback if radios fail, and SWMS sign-on.

Set-up then follows the order drivers will meet things, one approach at a time, with the controllers spotting for each other.

1. Ute at the north end parked off the road with beacons on, clear of the station sight line.
2. North approach advance signs in TGS order, including the reduced speed signs and PREPARE TO STOP.
3. North station signs and the STOP HERE WHEN DIRECTED position.
4. South approach advance signs, starting from the far side of the crest and working towards the site. Here the supervisor drives over the crest at the posted speed after each sign goes out.
5. South station signs and position.
6. Delineation of the shuttle lane and work area per the TGS.
7. Permanent 100 km/h signs inside the reduced zone covered, fixed against wind.

The radio check. TC 1 and TC 2 test radios from their actual stations, not from the utes. In our example, TC 2 at the south station can hear TC 1 clearly, but the transmission breaks up when TC 2 steps slightly into the cutting on the low side of the road. The fix: TC 2's station stays on the higher shoulder where reception is clean, and the escape route is re-checked from there. The backup is agreed: if contact drops for more than the briefed period, both ends hold on STOP and the supervisor drives through. Our guide to traffic control radio communication covers call formats and fallbacks.

The drive-through: what drivers over the crest actually see

Before the first stop, the supervisor drives each approach at the speed the signs ask for, then again at the posted speed, because some drivers will ignore the reduction.

Northbound, over the crest, the supervisor looks for three things: the first sign seen early enough to read, the PREPARE TO STOP sign seen before the descent levels out, and the controller at the south station visible from far enough back to stop comfortably.

In our example, the low morning sun is directly behind TC 2 for northbound drivers. The controller is backlit and hard to see. The supervisor cannot move the station off the TGS position without approval, so they call the designer, explain the problem, and get approval to move the station a short way to a spot in front of a dark tree line where TC 2 stands out. The approval, time and reason go in the site diary. By mid-morning the sun has moved, but the new station stays because it is now the approved one.

Running the shuttle: the calls and the first problem

Stop/slow on a rural road runs on clear, repeated calls. The briefed format for this job:

• "North to South, stopping northbound... last vehicle is a red tray-back ute." (The controller showing SLOW stops their traffic and calls the last vehicle.)
• "South copies, red tray-back ute." Once it passes: "Red ute clear, releasing southbound."
• "Holding for the tipper" when plant needs the lane.

At 8:10 am, the first real problem: a stock truck heading north reaches TC 2 as TC 2 turns the bat to STOP. The truck stops, but late, and heavily. Heavy vehicles need more distance to stop than cars, and a truck coming down from the crest has momentum. TC 2 notes it, and from then on avoids stopping traffic with a heavy vehicle as the first vehicle where a safe gap allows. The near miss goes in the diary with the time and vehicle description. See the bat technique guide for stop and release sequences.

Managing the back of the queue over the crest

At 8:30 am the school bus run coincides with the tipper leaving. Southbound release is delayed while the tipper turns, and the northbound queue grows to about 12 vehicles. TC 2 sees the back of the queue approaching the PREPARE TO STOP sign and calls the supervisor.

The supervisor's options, in order:

1. Shorten the hold. Hold the tipper until the queue clears; plant can wait, the crest cannot.
2. Warn earlier. If the TGS includes an end-of-queue warning option, deploy it. In this example it does: a spare controller position with a warning sign is set up on the far side of the crest during the bus window.
3. Stop the work. If the queue still builds, stop the plant and run traffic until it clears.

The supervisor does not ask TC 2 to leave the station and walk back to move signs. The end-of-queue section in our guide to end-of-queue management at roadworks explains why this point is a recurring focus for road authorities, and NSW's TS 05492 adds requirements in this area.

Farm gates, relief and the long afternoon

Rural jobs bring their own interruptions.

• Farm gate access. At 11 am a farmer wants to leave a paddock gate inside the shuttle lane. TC 1 holds both ends, the supervisor walks the vehicle out and into the shuttle in the correct direction, and the release call accounts for it as the last vehicle.
• Relief. Controllers on the bat are relieved on a schedule briefed in the morning, with the supervisor or a third person taking the station. A relief break is not more traffic control.
• Heat and fatigue. A long rural day in the sun slows reactions. Water at each station, shade where possible, and the supervisor watching for drifting or missed calls.
• Inspections. The layout is inspected at start, at suitable intervals and at end of shift, with findings recorded.

Pack-down and the record

Pack-down runs in reverse: stop the work, clear plant from the shuttle lane, remove work area delineation, then each approach from the station back to the furthest sign, with the crest approach handled last and with a spotter. Covers come off the permanent signs. The supervisor drives both approaches one final time.

For the national guidance, check Austroads; in Queensland, Transport and Main Roads; in NSW, Transport for NSW. Check the current version of the manual your project specifies.

Next steps

Before your next rural stop/slow job, do the queue maths with real counts, drive every approach at the posted speed, and test radios from the stations themselves. Operators can roster relief controllers with fatigue checks and capture pre-starts and dockets on the crew's phones in TrafWise.