Provenance
Exploratory method-comparison artifact. NOT a published chart. No ArcGIS File GDB / product shapefile release while vertical datum is parked.
Surveys
| Survey ID | Source | Soundings (approx.) |
|---|---|---|
| H07599 | NOS/NCEI GEODAS XYZ | ~5,087 |
| H07600 | NOS/NCEI GEODAS XYZ | ~9,966 |
| H07601 | NOS/NCEI GEODAS XYZ | ~18,562 |
| Total | concatenated extracts | ~33,609 kept |
Distributor: NOAA National Centers for Environmental Information (NCEI) / GEODAS. Access / run date: 2026-10-07 (America/Los_Angeles). Collection DOI: https://doi.org/10.25921/qh2z-7261 · CC0-1.0. License for display: NOS hydrographic digital extracts are CC0 / public domain — OK to cite with provenance + disclaimer.
Horizontal CRS
| Role | EPSG | Notes |
|---|---|---|
| Source soundings | 4269 | NAD83 geographic lon/lat as delivered |
| Staging / project (locked) | 2243 | NAD83 / Idaho West (ftUS), FIPS 1103 |
| Meter twin (reference) | 26970 | Not 26971 (Illinois East) |
This viewer’s heatmap / overlay PNGs were built from the geographic copy
(EPSG:4269 lon/lat). Projected TIN/IDW staging lives in the engineering pack
(crs-idaho-west/). Face copy cites EPSG:2243 as the staging CRS.
Depth / vertical
| Item | Value |
|---|---|
| Source / grid units | meters (NOS digital) |
| Depth range kept | 0.0 … 353.0 m (≈ 1158 ft deep basin — real, not clipped) |
| Vertical datum | PARKED / TBD (B2) — face copy: datum TBD |
| Product display | feet via depth_ft = depth_m × 3.280839895 |
| Default contours | 10 ft; majors every 50 ft; tunable ≥ 2 ft |
Interpolation
- TIN: scipy Delaunay + LinearNDInterpolator
- IDW: k=12, power=2.0, hull-masked to TIN
- Palette: Structure Signal default (classified breaks; 12 selectable)
- Product lock: TIN ↔ IDW toggle required on viewer
Shoreline
Shoreline: USGS National Hydrography Dataset (NHD/NHDPlus HR) waterbody, accessed 2026-10-07.
Product: USGS NHD Waterbody (Large Scale / High Resolution), The National Map ·
feature Permanent_Identifier 120026590 · GNIS_ID 00398523 (Lake Pend Oreille) ·
FCode 39009 · public domain.
Source: hydro.nationalmap.gov nhd/MapServer/12 · accessed 2026-10-07 ·
staged in EPSG:2243 as Shoreline_NHD.
Basemap: soft land fill only — no map tiles, no OpenStreetMap data.
NHD is the average/visible water edge; no full-pool claim (vertical datum TBD).
Boat launches (BETA)
Public access points: Idaho Department of Fish and Game — “IDFG Fishing and Boating Access Sites Public” (copyright IDFG, IFWIS), ArcGIS REST
https://gisportal-idfg.idaho.gov/hosting/rest/services/Access/IDFG_Fishing_and_Boating_Access_Sites_Public/FeatureServer/0,
queried by envelope around the lake, accessed 2026-10-14. 7 sites kept (Cocolalla Lake and Shepherd Lake removed as separate waterbodies). Vendored as
assets/access/pend-oreille-idfg-access.geojson; no runtime request. Only IDFG-managed or co-managed sites, so other public launches (for example USFS, county or city) are not listed. No OpenStreetMap data.
Beta tools
Depth readout, highlight, cross-section and slope all sample the same TIN/IDW feet grid (473×500). Slope is computed in the browser from neighboring cells (degrees). The water-level offset is a display offset only — not a datum correction; vertical datum TBD. A future option may fill it from USGS gauge 12392500 (Lake Pend Oreille near Hope, ID). That is not wired up.