Brúarfoss waterfall from a different angle than the usual pov This guide tells people to drive through land that is private property.
The correct route would be to park the car by the bridge over Brúará (on road nr. 37) and walk upstream to Brúarfoss (walk on the east side of the river). There is plenty of space to park by that bridge. Also, if you walk upstream from the main road you get to see the other two waterfalls as well. Its well worth it