Thanks for the pickup Jono. My mistake, I thought I'd found the right tags but apparently not. Your changes are great, thanks for fixing it up.

Sorry, yea it's probably a culvert instead. I've corrected this in this changeset. osm.org/changeset/92796189

Corrected in changeset 90894777 here: osm.org/changeset/90894777

Thanks jon. I'll revert that change.