Unable to answer "What’s the surface here?" for https://osm.org/way/1112478615 via StreetComplete 49.0:

Footbridge over lock gates

Attached photo(s):
https://westnordost.de/p/121118.jpg
https://westnordost.de/p/121119.jpg
https://westnordost.de/p/121120.jpg
https://westnordost.de/p/121121.jpg
https://westnordost.de/p/121122.jpg