Europe's most powerful waterfall moves 500 cubic meters per second. Hydropower calculations show it could generate 100 megawatts, but it's protected as a natural monument.
Tbc, Public domain, via Wikimedia Commons
A River's Engine
Dettifoss contains a large amount of kinetic energy. The waterfall is approximately 100 meters (330 ft) wide and drops 44 meters (144 ft). Its power originates from the Jökulsá á Fjöllum river, Iceland's second-longest, which flows 206 kilometers from the Vatnajökull glacier, the largest ice cap in Europe. The river's average flow is about 193 cubic meters per second (m³/s), but during summer melts, this volume can surge to 500 m³/s or even higher during flood events.
This immense flow, combined with the significant vertical drop, gives the waterfall its power. Hydropower potential is a direct function of flow rate and height, and Dettifoss possesses both in abundance. The water itself is not clear; it has a characteristic greyish-white color due to a heavy load of suspended sediment—glacial flour—scoured from the volcanic rock beneath the Vatnajökull glacier. This constant abrasion is a powerful erosive force, with the waterfall carving its way southwards through the rock ledge at a rate of about half a meter per year. The sheer force of the water is tangible, causing the surrounding cliffs to vibrate.
A Natural Monument Over a Power Plant
The idea of harnessing the Jökulsá á Fjöllum for electricity is not new. Iceland began developing hydroelectric power in the early 20th century, and by the 1960s, was constructing large-scale stations to power energy-intensive industries. Proposals to dam the Jökulsá á Fjöllum and utilize the power of Dettifoss were discussed. In 2015, Iceland's National Energy Authority even published draft suggestions that included two power plants on the river, which would have affected Dettifoss.
These plans never materialized for both practical and philosophical reasons. Geologic analysis revealed that the porous volcanic basalt bedrock in the Jökulsárgljúfur canyon would make it difficult to create a stable and watertight reservoir. More importantly, a growing movement for conservation recognized the unique natural value of the waterfall and its surrounding landscape. The area was first protected as a natural monument in 1996. Later, it was incorporated into the much larger Vatnajökull National Park, established in 2008. This designation protects the entire series of waterfalls on this stretch of the river—including Selfoss 1 kilometer upstream and Hafragilsfoss 2 kilometers downstream—ensuring the river's energy is a force of nature and not a source of electricity.
💡Fun Facts
The waterfall appeared in the opening scene of the 2012 Ridley Scott science fiction film "Prometheus."
The Jökulsárgljúfur canyon, where Dettifoss is located, was carved not by gradual erosion but by a series of catastrophic glacial outburst floods, known as jökulhlaups.
The river's sediment load is among the highest in Iceland, carrying millions of tons of material to the sea each year.
The waterfall's name, Dettifoss, translates to "The Collapsing Waterfall" or "Tumbling Falls."
The area is accessible 24/7, but road access is highly dependent on weather and season. The west side road (862) has better winter service, while the east side road (864) is a gravel road often closed from autumn until late spring.
Admission
Free
Accessibility
The waterfall can be viewed from both an east and west bank, connected by separate roads. The west bank has a paved road (862), more facilities including toilets, and maintained hiking paths. The east bank is reached by a gravel road (864) and is considered to offer more dramatic, closer views but has fewer amenities. The terrain around the falls is rocky and uneven, and spray can make paths slippery.
