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Elevation Data Processing

Elevation data provides crucial terrain information for route planning, helping identify steep grades and elevation changes that affect caravan towing.

Overview​

Data Source: SRTM (Shuttle Radar Topography Mission) 90m Digital Elevation Model

Coverage: All of Australia (4.3 million road segments)

Processing: Background process calculating elevation profiles for all road segments

What's Calculated​

For each road segment, the system calculates:

  • Start/end elevation
  • Minimum/maximum elevation
  • Elevation gain/loss
  • Average grade percentage
  • Maximum grade percentage
  • Grade category (flat, gentle, moderate, steep, very_steep)

Data Source​

SRTM 90m DEM​

  • Resolution: 90 meters
  • Tiles: 31 tiles covering all of Australia
  • Source: EarthExplorer (USGS)
  • Format: GeoTIFF (.tif files)

Coverage by State:

  • Western Australia (WA)
  • South Australia (SA)
  • Northern Territory (NT)
  • Victoria (VIC)
  • New South Wales (NSW)
  • Queensland (QLD)
  • Tasmania (TAS)

Processing Scripts​

Smart Elevation Processing​

Script: scripts/process-all-elevations-smart.ts

Features:

  • Loads SRTM tiles once at startup
  • Processes all segments with progress tracking
  • Match rate: ~69% (segments with elevation data)
  • Imports in batches of 1000

Command:

# Process all segments
npm run db:process-elevations

# Check progress
npm run db:check-elevation-progress

Download SRTM Tiles​

Script: scripts/download-srtm-tiles.sh

Downloads required SRTM tiles for Australia from Earth Explorer.

Command:

./scripts/download-srtm-tiles.sh

Performance​

Processing Rate: ~1,000 segments/minute Import Rate: ~700 elevation records/minute Estimated Time: 48-72 hours for all 4.3 million segments

Grade Categories​

Segments are categorized by maximum grade:

CategoryGrade RangeCaravan Impact
Flat0-2%✅ Easy
Gentle2-5%✅ Easy
Moderate5-8%⚠️ Caution
Steep8-12%⚠️ Difficult
Very Steep>12%❌ Avoid

Monitoring Progress​

Check Status​

npm run db:check-elevation-progress

View Progress File​

cat packages/database/scripts/.elevation-smart-progress.json

Example output:

{
  "totalSegments": 4300000,
  "processedSegments": 58000,
  "percentComplete": 1.35,
  "lastProcessedId": "uuid-here",
  "timestamp": "2025-10-14T10:30:00Z"
}

Watch Live Processing​

tail -f ~/Downloads/elevation-australia-FULL.log

Database Schema​

Elevation Records Table​

CREATE TABLE segment_elevations (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  segment_id UUID REFERENCES route_segments(id) NOT NULL,
  start_elevation DECIMAL(7, 2),
  end_elevation DECIMAL(7, 2),
  min_elevation DECIMAL(7, 2),
  max_elevation DECIMAL(7, 2),
  elevation_gain DECIMAL(7, 2),
  elevation_loss DECIMAL(7, 2),
  avg_grade DECIMAL(5, 2),
  max_grade DECIMAL(5, 2),
  grade_category grade_category_enum,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);

Usage Examples​

Find Steep Segments Along Route​

const { data } = await supabase
  .from('route_segments')
  .select('*, segment_elevations(*)')
  .gte('latitude', minLat)
  .lte('latitude', maxLat)
  .filter('segment_elevations.max_grade', 'gt', 8);

Get Elevation Profile for Route​

const { data } = await supabase
  .from('route_segments')
  .select('id, geometry, segment_elevations(start_elevation, end_elevation, max_grade)')
  .in('id', segmentIds)
  .order('sequence_number');

Status​

Implementation: In Progress Current Progress: Processing elevation data for all segments Estimated Completion: 48-72 hours for full Australia coverage

Future Enhancements​

  1. Higher Resolution DEMs: Use 30m or 10m resolution where available
  2. Real-time Updates: Automatically process new segments
  3. Elevation Alerts: Warn users of steep grades on planned routes
  4. Elevation Charts: Visualize elevation profiles in mobile app