From OpenStreetMap Wiki
|This key shows if a shared path is segregated or not.|
|Used on these elements|
|Documented values: 2|
|Tools for this tag|
This key is used for combined cycle- and footways. If both have their own lane tag segregated=yes. If they share one lane tag segregated=no. This key has no default value and should be tagged on all shared ways!
|* highway=cycleway/footway/path + bicycle=designated + foot=designated + segregated=yes|
|highway=cycleway/footway/path + bicycle=designated + foot=designated + segregated=no|