{
 "ocl_version": "0.1.0",
 "name": "Thomas Hill Road",
 "slug": "thomas-hill-road",
 "confidence": "A",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 53.40135803219539,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 999.0,
   "end_distance_m": 1001.0,
   "start_elevation_m": 492.9706828789182,
   "end_elevation_m": 494.0387100395621,
   "min_gradient_pct": -39.14602694695759
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 43.93254441069985,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 999.0,
   "end_distance_m": 1002.0,
   "start_elevation_m": 492.9706828789182,
   "end_elevation_m": 494.2886592112392,
   "min_gradient_pct": -31.869858247944194
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 34.105314239850486,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 998.0,
   "end_distance_m": 1003.0,
   "start_elevation_m": 492.73384161848594,
   "end_elevation_m": 494.43910733047846,
   "min_gradient_pct": -17.5513121455117
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 26.191910434795886,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 894.0,
   "end_distance_m": 904.0,
   "start_elevation_m": 478.20981029688124,
   "end_elevation_m": 480.82900134036083,
   "min_gradient_pct": -5.768123506847473
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 22.326162356476118,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 956.0,
   "end_distance_m": 976.0,
   "start_elevation_m": 487.1297752253274,
   "end_elevation_m": 491.59500769662264,
   "min_gradient_pct": -5.4252927957253405
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 20.86306471494504,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 894.0,
   "end_distance_m": 919.0,
   "start_elevation_m": 478.20981029688124,
   "end_elevation_m": 483.4255764756175,
   "min_gradient_pct": -5.189615600532079
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 17.89063959475675,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 868.0,
   "end_distance_m": 918.0,
   "start_elevation_m": 474.26505683141784,
   "end_elevation_m": 483.2103766287962,
   "min_gradient_pct": -4.279119732698405
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 15.940974855601326,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 884.0,
   "end_distance_m": 984.0,
   "start_elevation_m": 476.81896337818165,
   "end_elevation_m": 492.759938233783,
   "min_gradient_pct": -2.842464955906621
  }
 ],
 "shape": {
  "ascent_concentration": 0.414,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 256.0,
  "shape_class": "sustained"
 },
 "length_m": 2820.7370606419054,
 "start_elevation_m": 379.9957485420002,
 "end_elevation_m": 559.2793184120568,
 "endpoint_gain_m": 179.28356987005662,
 "overall_gradient_pct": 6.3559121611022364,
 "accumulated_ascent_m": 192.73754118816845,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 34.105314239850486,
   "start_distance_m": 998.0,
   "end_distance_m": 1003.0,
   "midpoint_distance_m": 1000.5,
   "start_elevation_m": 492.73384161848594,
   "end_elevation_m": 494.43910733047846,
   "start_xy": [
    688428.8493935453,
    4743402.141478159
   ],
   "end_xy": [
    688424.3447089458,
    4743399.971727791
   ]
  },
  "max_10m": {
   "gradient_pct": 26.191910434795886,
   "start_distance_m": 894.0,
   "end_distance_m": 904.0,
   "midpoint_distance_m": 899.0,
   "start_elevation_m": 478.20981029688124,
   "end_elevation_m": 480.82900134036083,
   "start_xy": [
    688522.3404573968,
    4743447.673748174
   ],
   "end_xy": [
    688513.5374640148,
    4743442.932785079
   ]
  },
  "max_20m": {
   "gradient_pct": 22.326162356476118,
   "start_distance_m": 956.0,
   "end_distance_m": 976.0,
   "midpoint_distance_m": 966.0,
   "start_elevation_m": 487.1297752253274,
   "end_elevation_m": 491.59500769662264,
   "start_xy": [
    688466.6887441806,
    4743420.367381251
   ],
   "end_xy": [
    688448.6700057829,
    4743411.6883797785
   ]
  },
  "max_25m": {
   "gradient_pct": 20.86306471494504,
   "start_distance_m": 894.0,
   "end_distance_m": 919.0,
   "midpoint_distance_m": 906.5,
   "start_elevation_m": 478.20981029688124,
   "end_elevation_m": 483.4255764756175,
   "start_xy": [
    688522.3404573968,
    4743447.673748174
   ],
   "end_xy": [
    688500.0234102166,
    4743436.423533974
   ]
  },
  "max_50m": {
   "gradient_pct": 17.89063959475675,
   "start_distance_m": 868.0,
   "end_distance_m": 918.0,
   "midpoint_distance_m": 893.0,
   "start_elevation_m": 474.26505683141784,
   "end_elevation_m": 483.2103766287962,
   "start_xy": [
    688545.147722045,
    4743460.156883969
   ],
   "end_xy": [
    688500.9243471364,
    4743436.857484048
   ]
  },
  "max_100m": {
   "gradient_pct": 15.940974855601326,
   "start_distance_m": 884.0,
   "end_distance_m": 984.0,
   "midpoint_distance_m": 934.0,
   "start_elevation_m": 476.81896337818165,
   "end_elevation_m": 492.759938233783,
   "start_xy": [
    688531.1124822615,
    4743452.474954249
   ],
   "end_xy": [
    688441.4625104237,
    4743408.21677919
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -17.5513121455117,
   "start_distance_m": 990.0,
   "end_distance_m": 995.0,
   "midpoint_distance_m": 992.5,
   "start_elevation_m": 493.39740295182946,
   "end_elevation_m": 492.5198373445539,
   "start_xy": [
    688436.0568889044,
    4743405.613078749
   ],
   "end_xy": [
    688431.552204305,
    4743403.443328381
   ]
  },
  "min_10m": {
   "gradient_pct": -5.768123506847473,
   "start_distance_m": 1554.0,
   "end_distance_m": 1564.0,
   "midpoint_distance_m": 1559.0,
   "start_elevation_m": 509.6751250768854,
   "end_elevation_m": 509.0983127262007,
   "start_xy": [
    687883.3814807391,
    4743318.960895364
   ],
   "end_xy": [
    687873.3834434963,
    4743318.762775977
   ]
  },
  "min_20m": {
   "gradient_pct": -5.4252927957253405,
   "start_distance_m": 1553.0,
   "end_distance_m": 1573.0,
   "midpoint_distance_m": 1563.0,
   "start_elevation_m": 509.7303652523038,
   "end_elevation_m": 508.6453066931587,
   "start_xy": [
    687884.3812844635,
    4743318.980707303
   ],
   "end_xy": [
    687864.3852099779,
    4743318.58446853
   ]
  },
  "min_25m": {
   "gradient_pct": -5.189615600532079,
   "start_distance_m": 1550.0,
   "end_distance_m": 1575.0,
   "midpoint_distance_m": 1562.5,
   "start_elevation_m": 509.8618519590881,
   "end_elevation_m": 508.56444805895507,
   "start_xy": [
    687887.3806956363,
    4743319.040143119
   ],
   "end_xy": [
    687862.3856025293,
    4743318.544844652
   ]
  },
  "min_50m": {
   "gradient_pct": -4.279119732698405,
   "start_distance_m": 1550.0,
   "end_distance_m": 1600.0,
   "midpoint_distance_m": 1575.0,
   "start_elevation_m": 509.8618519590881,
   "end_elevation_m": 507.7222920927389,
   "start_xy": [
    687887.3806956363,
    4743319.040143119
   ],
   "end_xy": [
    687837.4670562164,
    4743316.9698990695
   ]
  },
  "min_100m": {
   "gradient_pct": -2.842464955906621,
   "start_distance_m": 1544.0,
   "end_distance_m": 1644.0,
   "midpoint_distance_m": 1594.0,
   "start_elevation_m": 509.9934781732027,
   "end_elevation_m": 507.15101321729605,
   "start_xy": [
    687893.3795179819,
    4743319.159014751
   ],
   "end_xy": [
    687795.8519524888,
    4743327.631429131
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 53.40135803219539,
   "start_distance_m": 999.0,
   "end_distance_m": 1001.0,
   "midpoint_distance_m": 1000.0,
   "start_elevation_m": 492.9706828789182,
   "end_elevation_m": 494.0387100395621,
   "start_xy": [
    688427.9484566253,
    4743401.707528086
   ],
   "end_xy": [
    688426.1465827856,
    4743400.839627939
   ]
  },
  "max_3m": {
   "gradient_pct": 43.93254441069985,
   "start_distance_m": 999.0,
   "end_distance_m": 1002.0,
   "midpoint_distance_m": 1000.5,
   "start_elevation_m": 492.9706828789182,
   "end_elevation_m": 494.2886592112392,
   "start_xy": [
    688427.9484566253,
    4743401.707528086
   ],
   "end_xy": [
    688425.2456458657,
    4743400.405677865
   ]
  }
 },
 "diagnostic_note": "Windows <=3 m are at raster-noise scale (1-sigma raster noise alone is roughly +/-7 pp at 2 m and +/-5 pp at 3 m on a 1 m DTM). Diagnostic use only: never a headline or ranking value.",
 "quality_summary": {
  "review": [],
  "extent": [
   "may_start_earlier"
  ]
 },
 "provenance": {
  "analysis_version": "0.1.0",
  "sample_interval_m": 1.0,
  "interpolation": "bilinear",
  "smoothing": "none",
  "gradient_windows_m": [
   5.0,
   10.0,
   20.0,
   25.0,
   50.0,
   100.0
  ],
  "diagnostic_windows_m": [
   2.0,
   3.0
  ],
  "elevation_crs": "EPSG:26918",
  "elevation_resolution_m": 1.0,
  "elevation_tiles": [
   "data/cache/usa/vt/USGS_1M_18_x68y475_VT_Statewide_A23.tif"
  ],
  "calculated_at": "2026-08-25T00:51:46+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/vermont-260821.osm.pbf",
  "osm_snapshot": "2026-08-21T20:21:11Z",
  "run_id": "redo-vt-1-260824",
  "elevation_provider": "USGS 3DEP (The National Map)",
  "elevation_licence": "Public domain \u2014 USGS 3DEP 1 m DEM, courtesy of the U.S. Geological Survey",
  "elevation_dataset": "USGS 3DEP 1 m DEM, VT_Statewide_A23 (collected 2023)",
  "elevation_tile_ids": [
   "x68y475"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 14.3% over 200 m (Terrain 50), gain 179.6 m over 2821 m way. KEPT at seed extent: no ascending continuation (min_avg=2.0%). ADOPTED (NE wave 1, 2026-08-25): clean-steep. Wales dials per PRODUCTION 'US ADOPTION DIALS'.",
  "canopy_check": "unavailable \u2014 EPT corridor failed: VT_Statewide_2_A23: no EPT nodes intersect the corridor; VT_Statewide_1_A23: no EPT nodes intersect the corridor",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
 "area": {
  "place": "Halifax",
  "county": "Vermont"
 }
}