Mangrt stream is the left tributary of the Predelica, which flows along the Mangrt Valley, and it is mainly dry in the upper more gradual part.

Water sinks into the sandbanks, which spread to the Mangrt alpine pasture, where it comes to the surface again and flows across the area of the glacier moraine which still fills up the stream in times of heavier rain.
It gets some more water from the right, from Sinji dol and from below Brlogi.

In the last part, since it was artificially dammed, it has been piercing through and forming beautiful troughs with numerous pools and waterfalls for millennia.