{
 "ocl_version": "0.1.0",
 "name": "Tunnel Road",
 "slug": "tunnel-road",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 24.731910456611672,
   "diagnostic": true,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 358.0,
   "end_distance_m": 360.0,
   "start_elevation_m": 424.1087310150701,
   "end_elevation_m": 424.6033692242023,
   "min_gradient_pct": -19.540376116810876,
   "suppressed_max_gradient_pct": 44.63412050870943,
   "suppressed_location_m": [
    343.0,
    345.0
   ]
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 22.579427240521,
   "diagnostic": true,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 357.0,
   "end_distance_m": 360.0,
   "start_elevation_m": 423.9259864069867,
   "end_elevation_m": 424.6033692242023,
   "min_gradient_pct": -18.710121649532613,
   "suppressed_max_gradient_pct": 42.82564131638461,
   "suppressed_location_m": [
    342.0,
    345.0
   ]
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 17.499813886083757,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 357.0,
   "end_distance_m": 362.0,
   "start_elevation_m": 423.9259864069867,
   "end_elevation_m": 424.80097710129087,
   "min_gradient_pct": -15.976459517836474,
   "suppressed_max_gradient_pct": 39.17040755575954,
   "suppressed_location_m": [
    341.0,
    346.0
   ]
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 17.09043678932403,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 308.0,
   "end_distance_m": 318.0,
   "start_elevation_m": 415.0645839082782,
   "end_elevation_m": 416.7736275872106,
   "min_gradient_pct": -12.554410734111912,
   "suppressed_max_gradient_pct": 32.96220940194246,
   "suppressed_location_m": [
    341.0,
    351.0
   ]
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 16.600065172661118,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 307.0,
   "end_distance_m": 327.0,
   "start_elevation_m": 414.90635722679565,
   "end_elevation_m": 418.2263702613279,
   "min_gradient_pct": -9.35377244482055,
   "suppressed_max_gradient_pct": 24.45302206578873,
   "suppressed_location_m": [
    333.0,
    353.0
   ]
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 16.370314383319737,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 306.0,
   "end_distance_m": 331.0,
   "start_elevation_m": 414.7509040204906,
   "end_elevation_m": 418.84348261632056,
   "min_gradient_pct": -8.660619190801071,
   "suppressed_max_gradient_pct": 22.452830363211433,
   "suppressed_location_m": [
    328.0,
    353.0
   ]
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 14.938125442999649,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 287.0,
   "end_distance_m": 337.0,
   "start_elevation_m": 412.1312308795206,
   "end_elevation_m": 419.60029360102044,
   "min_gradient_pct": -8.110194395411554,
   "suppressed_max_gradient_pct": 19.346280407692802,
   "suppressed_location_m": [
    303.0,
    353.0
   ]
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 12.514695490396491,
   "diagnostic": false,
   "flags": [
    "texture_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 788.0,
   "end_distance_m": 888.0,
   "start_elevation_m": 462.4808149917758,
   "end_elevation_m": 474.9955104821723,
   "min_gradient_pct": -7.559236990766806,
   "suppressed_max_gradient_pct": 15.211868701948788,
   "suppressed_location_m": [
    261.0,
    361.0
   ]
  }
 ],
 "shape": {
  "ascent_concentration": 0.42,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 219.0,
  "shape_class": "sustained"
 },
 "length_m": 997.6969876186007,
 "start_elevation_m": 411.13907160817723,
 "end_elevation_m": 480.3676636013143,
 "endpoint_gain_m": 69.22859199313706,
 "overall_gradient_pct": 6.938839432439155,
 "accumulated_ascent_m": 79.03776023268256,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 17.499813886083757,
   "start_distance_m": 357.0,
   "end_distance_m": 362.0,
   "midpoint_distance_m": 359.5,
   "start_elevation_m": 423.9259864069867,
   "end_elevation_m": 424.80097710129087,
   "start_xy": [
    668621.4127760306,
    4727916.575357654
   ],
   "end_xy": [
    668623.981598562,
    4727920.865013556
   ]
  },
  "max_10m": {
   "gradient_pct": 17.09043678932403,
   "start_distance_m": 308.0,
   "end_distance_m": 318.0,
   "midpoint_distance_m": 313.0,
   "start_elevation_m": 415.0645839082782,
   "end_elevation_m": 416.7736275872106,
   "start_xy": [
    668590.793030578,
    4727878.7006474985
   ],
   "end_xy": [
    668598.4243643127,
    4727885.159965043
   ]
  },
  "max_20m": {
   "gradient_pct": 16.600065172661118,
   "start_distance_m": 307.0,
   "end_distance_m": 327.0,
   "midpoint_distance_m": 317.0,
   "start_elevation_m": 414.90635722679565,
   "end_elevation_m": 418.2263702613279,
   "start_xy": [
    668590.0253400552,
    4727878.05982679
   ],
   "end_xy": [
    668604.029186218,
    4727892.201693927
   ]
  },
  "max_25m": {
   "gradient_pct": 16.370314383319737,
   "start_distance_m": 306.0,
   "end_distance_m": 331.0,
   "midpoint_distance_m": 318.5,
   "start_elevation_m": 414.7509040204906,
   "end_elevation_m": 418.84348261632056,
   "start_xy": [
    668589.2584745035,
    4727877.418019076
   ],
   "end_xy": [
    668606.5200605273,
    4727895.331477258
   ]
  },
  "max_50m": {
   "gradient_pct": 14.938125442999649,
   "start_distance_m": 287.0,
   "end_distance_m": 337.0,
   "midpoint_distance_m": 312.0,
   "start_elevation_m": 412.1312308795206,
   "end_elevation_m": 419.60029360102044,
   "start_xy": [
    668572.4763576399,
    4727869.007994164
   ],
   "end_xy": [
    668610.2565104329,
    4727900.026041988
   ]
  },
  "max_100m": {
   "gradient_pct": 12.514695490396491,
   "start_distance_m": 788.0,
   "end_distance_m": 888.0,
   "midpoint_distance_m": 838.0,
   "start_elevation_m": 462.4808149917758,
   "end_elevation_m": 474.9955104821723,
   "start_xy": [
    668815.3703761768,
    4728299.291684775
   ],
   "end_xy": [
    668912.5129767252,
    4728308.418110233
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -15.976459517836474,
   "start_distance_m": 50.0,
   "end_distance_m": 55.0,
   "midpoint_distance_m": 52.5,
   "start_elevation_m": 407.6349318151162,
   "end_elevation_m": 406.8361088392244,
   "start_xy": [
    668395.7636638209,
    4727718.115980965
   ],
   "end_xy": [
    668397.3445022342,
    4727722.859497226
   ]
  },
  "min_10m": {
   "gradient_pct": -12.554410734111912,
   "start_distance_m": 51.0,
   "end_distance_m": 61.0,
   "midpoint_distance_m": 56.0,
   "start_elevation_m": 407.5093092259279,
   "end_elevation_m": 406.2538681525167,
   "start_xy": [
    668396.0804869632,
    4727719.0644655945
   ],
   "end_xy": [
    668399.2424643441,
    4727728.551397666
   ]
  },
  "min_20m": {
   "gradient_pct": -9.35377244482055,
   "start_distance_m": 50.0,
   "end_distance_m": 70.0,
   "midpoint_distance_m": 60.0,
   "start_elevation_m": 407.6349318151162,
   "end_elevation_m": 405.7641773261521,
   "start_xy": [
    668395.7636638209,
    4727718.115980965
   ],
   "end_xy": [
    668404.8834307635,
    4727735.333541193
   ]
  },
  "min_25m": {
   "gradient_pct": -8.660619190801071,
   "start_distance_m": 49.0,
   "end_distance_m": 74.0,
   "midpoint_distance_m": 61.5,
   "start_elevation_m": 407.6792111919292,
   "end_elevation_m": 405.51405639422893,
   "start_xy": [
    668395.447432906,
    4727717.167298717
   ],
   "end_xy": [
    668407.785374686,
    4727738.086487978
   ]
  },
  "min_50m": {
   "gradient_pct": -8.110194395411554,
   "start_distance_m": 50.0,
   "end_distance_m": 100.0,
   "midpoint_distance_m": 75.0,
   "start_elevation_m": 407.6349318151162,
   "end_elevation_m": 403.5798346174104,
   "start_xy": [
    668395.7636638209,
    4727718.115980965
   ],
   "end_xy": [
    668426.646315415,
    4727755.982431732
   ]
  },
  "min_100m": {
   "gradient_pct": -7.559236990766806,
   "start_distance_m": 0.0,
   "end_distance_m": 100.0,
   "midpoint_distance_m": 50.0,
   "start_elevation_m": 411.13907160817723,
   "end_elevation_m": 403.5798346174104,
   "start_xy": [
    668367.839,
    4727678.293
   ],
   "end_xy": [
    668426.646315415,
    4727755.982431732
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 24.731910456611672,
   "start_distance_m": 358.0,
   "end_distance_m": 360.0,
   "midpoint_distance_m": 359.0,
   "start_elevation_m": 424.1087310150701,
   "end_elevation_m": 424.6033692242023,
   "start_xy": [
    668621.9266835356,
    4727917.433203256
   ],
   "end_xy": [
    668622.9544985455,
    4727919.148894459
   ]
  },
  "max_3m": {
   "gradient_pct": 22.579427240521,
   "start_distance_m": 357.0,
   "end_distance_m": 360.0,
   "midpoint_distance_m": 358.5,
   "start_elevation_m": 423.9259864069867,
   "end_elevation_m": 424.6033692242023,
   "start_xy": [
    668621.4127760306,
    4727916.575357654
   ],
   "end_xy": [
    668622.9544985455,
    4727919.148894459
   ]
  }
 },
 "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": {
  "texture_suppression": {
   "masked_fraction": 0.015,
   "windows_resited": [
    2.0,
    3.0,
    5.0,
    10.0,
    20.0,
    25.0,
    50.0,
    100.0
   ],
   "windows_unresolved": []
  },
  "texture_windows": {
   "rounds": 1,
   "windows_masked": [
    {
     "window_m": 10.0,
     "start_m": 341.0,
     "end_m": 351.0,
     "raw_pct": 32.96,
     "reason": "short-step"
    }
   ],
   "advisory": [],
   "unresolved": []
  },
  "overhead_obstruction": {
   "obstruction_threshold_m": 2.0,
   "obstructed_fraction": 0.707,
   "obstruction_max_height_m": 29.41,
   "flagged_windows_m": [
    2,
    3,
    5,
    10,
    20,
    25,
    50,
    100
   ]
  },
  "excluded_ranges_m": [
   [
    339.0,
    353.0
   ]
  ],
  "review": [],
  "extent": [
   "descends_at_start"
  ]
 },
 "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/ma/USGS_1M_18_x66y473_MA_Western_B24.tif"
  ],
  "calculated_at": "2026-09-11T23:06:06+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "output/texture-us-ma/batch-usa-rchunk05.pbf",
  "osm_snapshot": "",
  "run_id": "texture-us-ma-260911",
  "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, MA_Western_B24 (collected 2023-24)",
  "elevation_tile_ids": [
   "x66y473"
  ],
  "climb_origin": "discovered",
  "canopy_source": {
   "kind": "ept_corridor_max_return",
   "ept_source": "https://usgs-lidar-public.s3-us-west-2.amazonaws.com/USGS_LPC_MA_ME_MA_QL2_UTM18_L1_2015_LAS_2018",
   "ept_crs": "EPSG:3857",
   "station_coverage": 0.993,
   "cell_ground_m": 1.0,
   "nodes_failed": 0
  },
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing"
 },
 "area": {
  "place": "Rowe",
  "county": "Massachusetts"
 }
}