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Understanding Road Hazards

VanRoute tracks over 57,000 road hazards across Australia that could affect caravans, motorhomes, and large vehicles. This guide explains each hazard type and how to navigate them safely.

Hazard Severity Levels​

All hazards are categorized by severity relative to YOUR specific vehicle:

🔴 Critical Hazards​

Definition: Hazards that pose immediate danger to your vehicle

Examples:

  • Bridge clearance less than your vehicle height + 30cm
  • Road width less than your vehicle width + 20cm
  • Weight limit less than your vehicle mass + 500kg
  • Extremely steep grades (>15%)

What to do:

  • Find alternative route - Do not attempt passage
  • Report if clearance info seems incorrect
  • Plan route avoiding this hazard

🟡 Moderate Hazards​

Definition: Hazards requiring caution and reduced speed

Examples:

  • Bridge clearance between vehicle height + 30cm and + 50cm
  • Road width between vehicle width + 20cm and + 100cm
  • Weight limits close to vehicle mass
  • Steep grades (8-15%)
  • Sharp corners

What to do:

  • Proceed with caution
  • Reduce speed
  • Check for oncoming traffic
  • Verify clearance visually
  • Have spotter for tight clearances

🟢 Minor Hazards​

Definition: Hazards requiring awareness but generally safe

Examples:

  • Bridge clearance > vehicle height + 50cm
  • Road width > vehicle width + 100cm
  • Weight limits well above vehicle mass
  • Moderate grades (5-8%)
  • Unsealed but well-maintained roads

What to do:

  • Normal driving with awareness
  • Note location for return journey
  • Monitor conditions

Hazard Types​

Height Restrictions​

What they are:

  • Bridges with limited vertical clearance
  • Underpasses and tunnels
  • Railway overpasses
  • Power lines (rare)

Measured from:

  • Road surface to lowest point of bridge/structure
  • May vary across road width
  • Can change with road resurfacing

Critical information:

  • Clearance height - Exact measurement in meters
  • Sign posted height - What the road sign shows
  • Clearance across road - Full width or center only
  • Last verified - Date of last measurement

Common clearances in Australia:

  • Urban bridges: 3.0m - 4.5m
  • Railway overpasses: 4.2m - 5.0m
  • Motorway overpasses: 4.5m - 5.5m
  • Rural bridges: Variable (2.8m - 5.5m)

Safety margin:

  • VanRoute adds 30cm minimum safety margin
  • Road signs may be rounded down for safety
  • Roads can be resurfaced, reducing clearance
  • Suspension compression reduces effective height

Warning indicators:

  • 🔴 Red: Clearance less than vehicle + 30cm
  • 🟡 Yellow: Clearance less than vehicle + 50cm
  • 🟢 Green: Clearance greater than vehicle + 50cm

Width Restrictions​

What they are:

  • Narrow roads and bridges
  • Historical town centers
  • Mountain passes
  • Single-lane bridges
  • Tight turns

Measured by:

  • Usable road width (excluding gutters)
  • Narrowest point on route section
  • Width between barriers on bridges
  • Clearance through turns

Critical information:

  • Road width - Measurement in meters
  • Length - How long the restriction continues
  • Passing places - Are there pullouts?
  • One-way sections - Traffic control

Common widths:

  • Highway standard: >7m (3.5m each direction)
  • Rural roads: 5-7m
  • Narrow roads: 3-4m
  • Single lane: 2.5-3m
  • Very narrow: <2.5m

Safety considerations:

  • Allow 20cm clearance each side minimum
  • Wide vehicles may need to straddle center line
  • Check for oncoming traffic
  • Use passing places
  • Fold in mirrors if needed (check vehicle manual)

Warning indicators:

  • 🔴 Red: Width less than vehicle + 40cm
  • 🟡 Yellow: Width less than vehicle + 100cm
  • 🟢 Green: Width greater than vehicle + 100cm

Weight Restrictions​

What they are:

  • Load limits on bridges
  • Structural capacity limits
  • Pavement weight restrictions
  • Combination vehicle limits

Measured by:

  • Maximum gross vehicle mass (GVM)
  • Maximum gross combination mass (GCM)
  • Axle load limits
  • Point load restrictions

Critical information:

  • Weight limit - Tonnes (1000kg)
  • Applies to - Single vehicle or combination
  • Alternative route - Nearby heavier-rated crossing
  • Restriction details - Specific limitations

Common weight limits:

  • Urban bridges: 10-40 tonnes
  • Rural bridges: 15-50 tonnes
  • Heavy vehicle bridges: 60+ tonnes
  • Heritage bridges: May be 5-15 tonnes

Safety considerations:

  • Use loaded weight, not tare weight
  • Include all cargo, water, fuel, passengers
  • Know your Gross Combination Mass (GCM)
  • Check compliance plate
  • Allow margin for error

Warning indicators:

  • 🔴 Red: Limit less than vehicle + 500kg
  • 🟡 Yellow: Limit less than vehicle + 1000kg
  • 🟢 Green: Limit greater than vehicle + 1000kg

Unsealed Roads​

What they are:

  • Gravel roads
  • Dirt roads
  • Unsealed sections of highways
  • Bush tracks

Condition varies by:

  • Recent maintenance
  • Weather and rainfall
  • Traffic volume
  • Road age

Critical information:

  • Surface type - Gravel, dirt, sand, etc.
  • Length - Distance of unsealed section
  • Condition - Recent reports
  • 2WD suitable - Yes/No
  • Caravan suitable - Yes/No/Unknown

Surface types:

  • Graded gravel - Well maintained, generally suitable
  • Rough gravel - Corrugated, caution advised
  • Dirt/clay - Can be slippery when wet
  • Sand - 4WD may be required
  • Mixed - Variable conditions

Safety considerations:

  • Reduce speed significantly
  • Increase following distance
  • Watch for loose stones
  • Check insurance policy (some exclude unsealed roads)
  • Tire damage more common
  • Dust affects visibility

Warning indicators:

  • 🔴 Red: Not suitable for caravans
  • 🟡 Yellow: Rough surface, reduce speed
  • 🟢 Green: Well-maintained, caravan suitable

Steep Grades​

What they are:

  • Hill climbs and descents
  • Mountain passes
  • Escarpments
  • Valley crossings

Measured by:

  • Gradient percentage (rise over run × 100)
  • Length of grade
  • Average vs maximum grade
  • Direction (up or down)

Critical information:

  • Maximum grade - Steepest percentage
  • Length - Distance of steep section
  • Direction - Ascending or descending
  • Curve severity - Tight turns on grade

Gradient categories:

  • Mild: 0-5% (1 in 20) - Generally no issue
  • Moderate: 5-8% (1 in 12) - Caution advised
  • Steep: 8-12% (1 in 8) - Difficult for heavy vehicles
  • Very steep: 12-15% (1 in 7) - May require low gear
  • Extreme: >15% (1 in 6) - Avoid if possible

Safety considerations:

  • Ascending:

    • Select low gear before hill
    • Maintain momentum
    • Watch engine temperature
    • Use passing lanes

  • Descending:

    • Select low gear BEFORE descent
    • Do not ride brakes continuously
    • Allow brakes to cool if needed
    • Check brake temperature at bottom
    • Use engine braking

Warning indicators:

  • 🔴 Red: Grades >12% or >2km long
  • 🟡 Yellow: Grades 8-12% or 1-2km long
  • 🟢 Green: Grades 5-8% or <1km long

Sharp Turns and Corners​

What they are:

  • Hairpin bends
  • Switchbacks
  • Tight intersections
  • Roundabouts with small radius

Measured by:

  • Turn radius (meters)
  • Turn angle (degrees)
  • Road width through turn
  • Visibility

Critical information:

  • Turn radius - How tight the curve
  • Turn angle - How far you must turn (90°, 180°, etc.)
  • Width - Road width through curve
  • Visibility - Can you see oncoming traffic?

Turn categories:

  • Gentle: >50m radius
  • Moderate: 20-50m radius
  • Sharp: 10-20m radius
  • Hairpin: <10m radius

Safety considerations for large vehicles:

  • May need to use both lanes
  • Check for oncoming traffic first
  • Long vehicles may need to take wide entry
  • Offtracking can put rear wheels on shoulder
  • Trailer may cut corner (track inside vehicle)

Warning indicators:

  • 🔴 Red: Extremely tight, may require multi-point turn
  • 🟡 Yellow: Very sharp, use both lanes
  • 🟢 Green: Sharp but manageable

Other Restrictions​

Flood Prone Areas

  • Roads subject to flooding
  • Check conditions before travel
  • Never drive through floodwater

Bush Fire Risk

  • High-risk fire zones
  • Check fire danger ratings
  • Have evacuation plan

Tourist Season Congestion

  • Popular routes during holidays
  • Increased traffic and delays
  • Limited parking at destinations

Time Restrictions

  • Size/weight restrictions by time of day
  • Curfews in some urban areas
  • School zone restrictions

Hazard Data Sources​

VanRoute compiles hazard data from:

Government Databases​

  • State road authorities - Official bridge data
  • Transport departments - Weight and height limits
  • Local councils - Local road restrictions
  • National Heavy Vehicle Regulator - Route restrictions

Verified Sources​

  • OpenStreetMap - Community-verified data
  • Government surveys - Engineering assessments
  • Bridge inspection reports - Regular surveys

User Reports​

  • VanRoute user submissions
  • Photo verification
  • Crowd-sourced validation
  • Expert review

Quality Assurance​

  • Data verified against multiple sources
  • Regular updates and audits
  • User feedback integration
  • Professional validation

How to Report Hazard Issues​

If you find incorrect information:

Report Incorrect Data​

  1. Tap the hazard marker
  2. Tap Report Issue
  3. Select problem type:
    • Incorrect clearance measurement
    • Hazard no longer exists
    • Missing hazard
    • Incorrect location
    • Other issue
  4. Add details and photos
  5. Submit report

Add Missing Hazard​

  1. Tap and hold on map location
  2. Tap Report Hazard
  3. Select hazard type
  4. Enter measurements
  5. Add photo if possible
  6. Submit for review

Update Hazard Information​

  1. Tap hazard marker
  2. Tap Suggest Edit
  3. Update information
  4. Explain changes
  5. Submit for review

Verification process:

  • Reports reviewed within 48 hours
  • Cross-checked with other data
  • May request additional information
  • Updates published after verification

Regional Hazard Patterns​

New South Wales​

  • Many low railway bridges in Newcastle/Sydney
  • Narrow historic bridges in coastal towns
  • Weight restrictions on older rural bridges
  • Flood-prone areas in northern rivers

Victoria​

  • Numerous low railway overpasses in Melbourne
  • Narrow mountain passes in High Country
  • Heritage bridges with weight limits
  • Tight turns in Dandenong Ranges

Queensland​

  • Flood-prone areas in north
  • Weight restrictions on older timber bridges
  • Long unsealed sections in outback
  • Steep coastal ranges

South Australia​

  • Extensive unsealed roads in outback
  • Limited low bridges (flat terrain)
  • Long distances between services
  • Steep grades Adelaide Hills

Western Australia​

  • Vast unsealed road network
  • Few height restrictions
  • Long distances between fuel/services
  • Flooding in north during wet season

Tasmania​

  • Narrow winding mountain roads
  • Many older bridges with weight limits
  • Steep grades throughout state
  • Limited alternative routes

Northern Territory​

  • Extensive unsealed roads
  • Flood-prone in wet season
  • Limited infrastructure in remote areas
  • Extreme heat considerations

Australian Capital Territory​

  • Modern infrastructure (few restrictions)
  • Some steep grades around Canberra
  • Limited low clearances
  • Good road maintenance

Safety Best Practices​

Before You Travel​

  • Review all hazards on planned route
  • Check for road condition updates
  • Verify vehicle dimensions are correct
  • Plan alternative routes for critical hazards

During Travel​

  • Slow down when approaching hazards
  • Verify clearances visually
  • If in doubt, stop and assess
  • Trust your judgment over app data

Trust but Verify​

  • VanRoute data is usually accurate
  • Road conditions can change
  • Always verify critical clearances
  • Road signs are authoritative

Emergency Contacts​

  • 000 for emergencies
  • 13 11 26 for roadside assistance (NRMA/RACV/etc.)
  • Local council for road conditions
  • VanRoute support for app issues

Next Steps​