The wide Hvítá River flows southward, and about a kilometre above the falls it turns sharply to the right and flows down into a wide curved three-step "staircase" and then abruptly plunges in two stages (11 metres or 36 feet, and 21 metres or 69 feet) into a crevice 32 metres (105 ft) deep. The crevice, about 20 metres (66 ft) wide and 2.5 kilometres (1.6 mi) in length, extends perpendicular to the flow of the river. The average amount of water running down the waterfall is 140 cubic metres (4,900 cu ft) per second in the summer and 80 cubic metres (2,800 cu ft) per second in the winter. The highest flood measured was 2,000 cubic metres (71,000 cu ft) per second.
During the first half of the 20th century and some years into the late 20th century, there was much speculation about using Gullfoss to generate electricity. During this period, the waterfall was rented indirectly by its owners, Tómas Tómasson and Halldór Halldórsson, to foreign investors. However, the investors' attempts were unsuccessful, partly due to lack of money. The waterfall was later sold to the state of Iceland, and is now protected.. In the early 20th century foreign investors wanted to harness the power of Gullfoss to produce electricity. In 1907 Howells, an Englishman wanted to buy Gullfoss from Tómas Tómasson, a farmer who owned Gullfoss at this time. Tómas declined Howells´ offer to buy the waterfall but later he leased it to him. The farmer´s daughter, Sigriður Tómasdóttir who grew up on his father´s sheep farm sought to have the rental contract voided. Sigriður using her own saving hired a lawyer in Reykjavik to defend her case. The trial lasted years and Sigriður went several times barefoot on traitorous terrain to Reykjavik to follow up on her case. She even threatened to throw herself into the waterfall if the construction would begin. Her attempts failed in court but before any damage was done to the waterfall the contract was disposed due to the lack of payments of the