2026-08-16

Six new high-resolution bathymetry sources across four countries, restored drying-area rendering on macro-tidal coasts, and a hardened data pipeline behind them.

New coverage

• Norway, Svalbard and the Barents Sea — Kartverket's declassified 50 m sea terrain model, chart datum inshore (~z11).
• Brittany, France — SHOM's Litto3D coastal lidar at 5 m, the chart's first French source. Depths are corrected onto French chart datum per pixel by a new reference surface built from SHOM's own BATHYELLI model, validated against their per-port tables (median residual 0.00 m).
• England & Wales nearshore — three complementary sources: the Channel Coastal Observatory's multibeam surveys (0.25–4 m, the south and southwest coasts' first high-resolution coverage), the Environment Agency's multibeam archive (0.5 m, mostly east coast), and the DORIS seabed survey of the Dorset coast (1 m).
• German tidal estuaries — WSV's DGM-W river terrain models for the Elbe, Weser and Jade at 2 m, on the German chart datum.
• 25 large lakes gain real depths — Ladoga, Onega, Winnipeg, Great Bear, Great Slave, Vänern, Balkhash, Biwa, Champlain and more, from the Global Lake Database. These previously rendered as flat unknown-depth water, including a corrupt GEBCO patch across southern Lake Ladoga now replaced by digitised bathymetry.

Every source is licence-vetted per grid before it ships, and each carries its attribution and provenance in the tile metadata.

Chart fixes

• Drying areas no longer vanish on big-tide coasts. Large connected foreshores (Brittany, and any coast where high-resolution data meets a large tidal range) could be silently dropped from the vector chart during writing; 232 km² was missing around Saint-Malo alone. Fixed, with guards that make any recurrence a loud failure instead of a quiet hole.
• Tideless coasts no longer show phantom green foreshore. Drying-area tint is now gated on water that can actually dry, so lake and low-tide-range shorelines render as plain water.
• Style: the safety contour gets its own color and stronger emphasis, depth labels drop their units, hillshade is now a viewer option, and relief band edges align exactly with contour lines. These ship in the style package as @openwaters/seascape 0.3.0 on npm.

Pipeline

• Depth-area artifacts self-heal: corrupt or mistyped files on the build store are detected and repaired or refetched automatically.
• Raw source downloads are no longer retained after processing — the staged data is the durable record, cutting storage while keeping every build reproducible from mirrors.
• Build memory reservations refit from measured usage; planet builds should run roughly twice as fast.
• Weekly garbage collection re-rooted on the published mosaic, and the tile contract now carries a declared schema version.

Seascape is not an official Electronic Navigational Chart and is never a replacement for one. Not for navigational use.