{
 "ocl_version": "0.1.0",
 "name": "South Hill Road",
 "slug": "south-hill-road",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 22.29476111598956,
   "diagnostic": true,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 495.0,
   "end_distance_m": 497.0,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 276.68115222975143,
   "min_gradient_pct": -131.92239132879848,
   "suppressed_max_gradient_pct": 216.30925117091948,
   "suppressed_location_m": [
    29.0,
    31.0
   ]
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 22.040021325936248,
   "diagnostic": true,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 495.0,
   "end_distance_m": 498.0,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 276.89645764720973,
   "min_gradient_pct": -107.54651180463668,
   "suppressed_max_gradient_pct": 156.68981161500994,
   "suppressed_location_m": [
    29.0,
    32.0
   ]
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 21.27507977387154,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 495.0,
   "end_distance_m": 500.0,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 277.2990109961252,
   "min_gradient_pct": -65.5044735008579,
   "suppressed_max_gradient_pct": 97.8309833131118,
   "suppressed_location_m": [
    29.0,
    34.0
   ]
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 20.27580167259714,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 490.0,
   "end_distance_m": 500.0,
   "start_elevation_m": 275.2714308288655,
   "end_elevation_m": 277.2990109961252,
   "min_gradient_pct": -33.57279778561718,
   "suppressed_max_gradient_pct": 54.84926278870631,
   "suppressed_location_m": [
    29.0,
    39.0
   ]
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 19.62709844766806,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 709.0,
   "end_distance_m": 729.0,
   "start_elevation_m": 309.65193179354515,
   "end_elevation_m": 313.57735148307876,
   "min_gradient_pct": -16.426885125029287,
   "suppressed_max_gradient_pct": 31.606341524393855,
   "suppressed_location_m": [
    29.0,
    49.0
   ]
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 19.24889493694036,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 490.0,
   "end_distance_m": 515.0,
   "start_elevation_m": 275.2714308288655,
   "end_elevation_m": 280.0836545631006,
   "min_gradient_pct": -14.03347934397243,
   "suppressed_max_gradient_pct": 27.583671417763185,
   "suppressed_location_m": [
    29.0,
    54.0
   ]
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 18.654930890895344,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 480.0,
   "end_distance_m": 530.0,
   "start_elevation_m": 273.4508280529024,
   "end_elevation_m": 282.7782934983501,
   "min_gradient_pct": -11.358623106213372
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 17.99985851585859,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 473.0,
   "end_distance_m": 573.0,
   "start_elevation_m": 272.2737415316443,
   "end_elevation_m": 290.2736000475029,
   "min_gradient_pct": -9.012642371777133
  }
 ],
 "shape": {
  "ascent_concentration": 0.433,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 362.0,
  "shape_class": "sustained"
 },
 "length_m": 4737.152820895283,
 "start_elevation_m": 229.93866322005633,
 "end_elevation_m": 577.2996846481172,
 "endpoint_gain_m": 347.3610214280609,
 "overall_gradient_pct": 7.332696127004248,
 "accumulated_ascent_m": 372.2227750743416,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 21.27507977387154,
   "start_distance_m": 495.0,
   "end_distance_m": 500.0,
   "midpoint_distance_m": 497.5,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 277.2990109961252,
   "start_xy": [
    679223.1717360697,
    4849017.250418897
   ],
   "end_xy": [
    679227.3010585459,
    4849014.445735271
   ]
  },
  "max_10m": {
   "gradient_pct": 20.27580167259714,
   "start_distance_m": 490.0,
   "end_distance_m": 500.0,
   "midpoint_distance_m": 495.0,
   "start_elevation_m": 275.2714308288655,
   "end_elevation_m": 277.2990109961252,
   "start_xy": [
    679220.820234129,
    4849021.662950894
   ],
   "end_xy": [
    679227.3010585459,
    4849014.445735271
   ]
  },
  "max_20m": {
   "gradient_pct": 19.62709844766806,
   "start_distance_m": 709.0,
   "end_distance_m": 729.0,
   "midpoint_distance_m": 719.0,
   "start_elevation_m": 309.65193179354515,
   "end_elevation_m": 313.57735148307876,
   "start_xy": [
    679281.1024493554,
    4848849.6664777715
   ],
   "end_xy": [
    679273.9854922022,
    4848831.037289925
   ]
  },
  "max_25m": {
   "gradient_pct": 19.24889493694036,
   "start_distance_m": 490.0,
   "end_distance_m": 515.0,
   "midpoint_distance_m": 502.5,
   "start_elevation_m": 275.2714308288655,
   "end_elevation_m": 280.0836545631006,
   "start_xy": [
    679220.820234129,
    4849021.662950894
   ],
   "end_xy": [
    679236.5284624344,
    4849002.775417222
   ]
  },
  "max_50m": {
   "gradient_pct": 18.654930890895344,
   "start_distance_m": 480.0,
   "end_distance_m": 530.0,
   "midpoint_distance_m": 505.0,
   "start_elevation_m": 273.4508280529024,
   "end_elevation_m": 282.7782934983501,
   "start_xy": [
    679216.8015141564,
    4849030.809482507
   ],
   "end_xy": [
    679245.3647932281,
    4848990.657653157
   ]
  },
  "max_100m": {
   "gradient_pct": 17.99985851585859,
   "start_distance_m": 473.0,
   "end_distance_m": 573.0,
   "midpoint_distance_m": 523.0,
   "start_elevation_m": 272.2737415316443,
   "end_elevation_m": 290.2736000475029,
   "start_xy": [
    679215.0917848842,
    4849037.592341592
   ],
   "end_xy": [
    679272.4837225352,
    4848957.307054729
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -65.5044735008579,
   "start_distance_m": 11.0,
   "end_distance_m": 16.0,
   "midpoint_distance_m": 13.5,
   "start_elevation_m": 230.3171564249176,
   "end_elevation_m": 227.04193274987472,
   "start_xy": [
    679580.607749378,
    4849261.473119321
   ],
   "end_xy": [
    679580.1262718224,
    4849256.496355376
   ]
  },
  "min_10m": {
   "gradient_pct": -33.57279778561718,
   "start_distance_m": 11.0,
   "end_distance_m": 21.0,
   "midpoint_distance_m": 16.0,
   "start_elevation_m": 230.3171564249176,
   "end_elevation_m": 226.9598766463559,
   "start_xy": [
    679580.607749378,
    4849261.473119321
   ],
   "end_xy": [
    679579.6447942669,
    4849251.519591431
   ]
  },
  "min_20m": {
   "gradient_pct": -16.426885125029287,
   "start_distance_m": 9.0,
   "end_distance_m": 29.0,
   "midpoint_distance_m": 19.0,
   "start_elevation_m": 230.2487503796766,
   "end_elevation_m": 226.96337335467075,
   "start_xy": [
    679580.8003404001,
    4849263.463824899
   ],
   "end_xy": [
    679578.8744301781,
    4849243.55676912
   ]
  },
  "min_25m": {
   "gradient_pct": -14.03347934397243,
   "start_distance_m": 4653.0,
   "end_distance_m": 4678.0,
   "midpoint_distance_m": 4665.5,
   "start_elevation_m": 585.3173929338667,
   "end_elevation_m": 581.8090230978736,
   "start_xy": [
    678056.9076110538,
    4845433.93646082
   ],
   "end_xy": [
    678058.2637744747,
    4845408.992924755
   ]
  },
  "min_50m": {
   "gradient_pct": -11.358623106213372,
   "start_distance_m": 4653.0,
   "end_distance_m": 4703.0,
   "midpoint_distance_m": 4678.0,
   "start_elevation_m": 585.3173929338667,
   "end_elevation_m": 579.63808138076,
   "start_xy": [
    678056.9076110538,
    4845433.93646082
   ],
   "end_xy": [
    678063.4699635516,
    4845384.612669219
   ]
  },
  "min_100m": {
   "gradient_pct": -9.012642371777133,
   "start_distance_m": 4637.0,
   "end_distance_m": 4737.0,
   "midpoint_distance_m": 4687.0,
   "start_elevation_m": 586.3223627381193,
   "end_elevation_m": 577.3097203663422,
   "start_xy": [
    678054.2149397044,
    4845449.7072036145
   ],
   "end_xy": [
    678074.5815241657,
    4845352.499345643
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 22.29476111598956,
   "start_distance_m": 495.0,
   "end_distance_m": 497.0,
   "midpoint_distance_m": 496.0,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 276.68115222975143,
   "start_xy": [
    679223.1717360697,
    4849017.250418897
   ],
   "end_xy": [
    679224.8081593069,
    4849016.114703031
   ]
  },
  "max_3m": {
   "gradient_pct": 22.040021325936248,
   "start_distance_m": 495.0,
   "end_distance_m": 498.0,
   "midpoint_distance_m": 496.5,
   "start_elevation_m": 276.23525700743164,
   "end_elevation_m": 276.89645764720973,
   "start_xy": [
    679223.1717360697,
    4849017.250418897
   ],
   "end_xy": [
    679225.6391257199,
    4849015.5583804445
   ]
  }
 },
 "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": {
  "structure_suppression": {
   "masked_fraction": 0.008,
   "windows_resited": [
    2.0,
    3.0,
    5.0,
    10.0,
    20.0,
    25.0
   ],
   "windows_unresolved": []
  },
  "excluded_ranges_m": [
   [
    0.0,
    39.0
   ]
  ],
  "review": [],
  "extent": [
   "descends_at_start",
   "descends_at_end"
  ]
 },
 "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_x67y485_VT_Statewide_A23.tif"
  ],
  "calculated_at": "2026-08-24T21:18:28+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": [
   "x67y485"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 16.8% over 200 m (Terrain 50), gain 346.9 m over 4703 m way. EXTENDED by graph walk: +1 segment(s) at base, +0 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (NE wave 1, 2026-08-25): big-gain. Wales dials per PRODUCTION 'US ADOPTION DIALS'.",
  "canopy_check": "unavailable \u2014 EPT corridor failed: VT_Statewide_2_A23: no corridor points fetched; VT_Statewide_1_A23: no EPT nodes intersect the corridor",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
 "area": {
  "place": "Stockbridge",
  "county": "Vermont"
 }
}