Rijkswaterstaat water levels: is it worth wiring in? #198

Merged

viberfox-agent merged 1 commit from docs/197-rijkswaterstaat-water-levels into main

2026-08-30 00:16:15 +00:00

viberfox-agent commented

2026-08-30 00:16:12 +00:00

Collaborator

Closes #197

Merged by the autopilot (docs/direction.md) after every Actions job passed on the branch head.

Closes #197 Merged by the autopilot (docs/direction.md) after every Actions job passed on the branch head.

viberfox-agent added 1 commit

2026-08-30 00:16:13 +00:00

docs(direction): Rijkswaterstaat water levels checked and not taken 004d9b0b84

The frontier row promised "canal and river surfaces at their real height".
Checked read-only against the live service on 2026-08-30. The levels are real,
keyless and CC0; the client has nowhere to put them.

Value 5, "the frame budget is not negotiable", and value 3, "degrade, never
break", settle it as a pair. A water surface takes one height for the whole
cell, and over a canal that height is the quay: AHN does not measure water and
the banks are dilated inward to fill the hole. The sheet then sits on an 8 mm
coplanar ladder over a clipmap eight opaque layers deep that nothing cuts holes
in, its finest level 2.65 cm below the water. So the row is not a data wire-in,
it is a rewrite of the ground sheet into a solid, and the intermediate state --
water hidden under the basemap, the world visible through the missing bank -- is
a broken picture rather than a degraded one.

Value 1, "measured beats plausible", is the case for it and loses on the join:
a station carries no water-body identifier of any kind, so every polygon's level
would be a nearest-point guess against 705 points. Value 6 agrees -- with no
visible change available there is no --dump-state field an --expect could hold.

Measured here and recorded in the note: the endpoint has moved off
waterwebservices.rijkswaterstaat.nl (301 to a migration notice) to
ddapi20-waterwebservices.rijkswaterstaat.nl; the catalogue is 1,573,954 B with
2,498 locations of which 705 carry WATHTE; a station-hour is 3,374 B and 7
measurements at 10-minute cadence; four of six city centres have no station
within a kilometre.

Also taken, which the ticket left open: the size of the drop. AHN's DTM over the
Groningen Diepenring is no-data on the water and +1.1 to +4.6 m NAP on the
banks, against an anchor datum of +7.57 m and a register level of -0.91 m NAP --
a drop of two to five metres, far past the 8 mm the stack can hold.

Documentation only -- no crate is touched, so nothing here compiles.

Refs #197

viberfox-agent merged commit d83a3bd5e1 into main

2026-08-30 00:16:15 +00:00

viberfox-agent referenced this pull request

2026-08-30 00:16:16 +00:00

Rijkswaterstaat water levels: is it worth wiring in? #197

viberfox-agent referenced this pull request from a commit

2026-08-30 00:16:16 +00:00

Merge pull request 'Rijkswaterstaat water levels: is it worth wiring in?' (#198) from docs/197-rijkswaterstaat-water-levels into main