That's nice, but yea the stream connects all the the way to the dougava,  so it's atleast 5km long, i walked alongside it for quite a while and part of it is already shown on the map , it also has some minor ditches withch make it much wider in it's lower stretches, plavūpe is actually natural , it's been here for ever, those are kind of rare around Salaspils because the natural ones often get barried or covered especially because the build up of the town happened recently so there are new rodes and houses everywhere witch take the place of the natural streams, plavūpe used to be slightly bigger but in 80s and 90s from what i know houses were built on top of some of it's small tributerys, but the stream survives till this day, it's common to see ditches around here but not streams, i highly suggest following the stream, it's buetiful and the wildife is plentiful, it's good you cant Hunt around these parts