Given its relatively light flow, it can run dry (especially late in summer) if it hasn't rained for a while. The proprietor at the Vossestolen Hotel in Oppheim showed me a pair of photos he took when it was dry and the next day when a thunderstorm gave the falls new life.

You might also see this waterfall referred to as "Tvinnefossen," which is typical of many Norwegian features as they tend to have multiple spellings or called by different names.