Rivers that exist on 3DHP but don't exist above ground in real life are tagged, can I safely remove?

Help and support
1

Hey all, new mapper here,
Was mapping and someone has various waterways mapped out that don’t exist. They’re ripped directly from the NHD/3DHP and are present on those maps as Channel Lines but in person they are non existent and are trivially easy to prove as such since they pass almost entirely through houses and neighborhoods with no infrastructure. Currently they are mapped as ditches (they are DEFINITELY not ditches) and I wanted to see if I’d be best off editing them to be something else or just removing them entirely since I couldn’t find anything else on the topic, thanks

2

Can you link example case?

Are these cases of bogus data in original source?

Mapping canalized now underground waterways? (like river in Brussels)

Mapping former rivers?

Something else?

Maybe it is utterly unclear?

Have you left info about this thread to whoever imported them?

3

The link above shows an example that I found. From further research, the rivers listed like this one did exist at one point but were filled in around 2003 due to human development. From what I understand these should be deleted, yeah?

4

yes, if something was demolished it should be removed from OSM

note, if it was transformed into something else mapping this would be nice (for example deleting demolished building is good, but if remnants are visible then deleting building and mapping these ruins is even better)

if these are visible on best aerials for given area, then Lifecycle prefix - OpenStreetMap Wiki would be better to prevent accidental remapping (only for temporary keeping, once aerial updates these should be deleted)

and there is OHM if someone wants to record past

5

If they were genuinely filled, yes, but it’s rare for rivers to simply be filled in – the water has to go somewhere. More often, they’re channelized and covered over, producing a tunnel=yes or tunnel=culvert.

6

though if we have no idea what happened and whether they were rerouted - deleting now bad data is better than guessing

7

In this particular case, the area is relatively flat, low-lying, swampy land. That’s exactly the case where developers would fill in the swamp to make it suitable for development. And there aren’t any natural barriers that would make it difficult to divert the surface water elsewhere.

Maybe we don’t know for sure what happened – historical aerial imagery might help, e.g., from Copernicus – but it looks like you’ve already got the right idea of how to map the current situation.

8

They were filled in and replaced with various ponds and reservoirs connected via tunnels that I’m doing my best to map as is but the routing is effectively entirely distinct from the original set of rivers. I’ll either find something to source from or just try and look for the tunnel entrance points on aerial.