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Updated: Nov 13, 2021

By David John Smith

The Rocky Road

Located at the Svælgfos waterfall at the head of a deep and narrow river gorge, Svælgfos I was the first power plant that Hydro built, the second largest in the world at the time. Supplying power directly to the Calcium Nitrate Factory in Notodden four kilometres to the south, this power plant was internationally known as a pioneer plant in hydroelectric power production.

A smooth flow of electricity was essential, and without it production in Notodden would stop. By then, in October 1907, a new factory had been put into operation with increased capacity. Located on the eastern side of the Test Factory, this was the very first full-scale Hydro production facility processing nitrogen for the manufacturing of mineral fertiliser.

Svælgfos Lightning Arrester House and Workshop

Upon completion, Svælgfos I had persistent problems and was plagued by unstable operations for several years. These problems included generators burning out – which had an effect on the Hydro production operations to the south, since the power was being transmitted directly south to Notodden.

A challenge was that there were few power plants the size of Svælgfos I, but Hydro did learn that power plants in Paris, Hamburg and Mexico all experienced some similar problems.

A group of electrical experts were brought together, and the conclusion made that the commutator that switched power to the rotor coils was not correctly constructed. The result was that such high temperatures were generated that the insulation burnt out.

The solution for a smooth flow of electricity would be the construction of a separate lightning arrester house believed to be the largest in the world at the time. This was indicative of Hydro’s ongoing processes to find solutions to problems with new innovations that were being implemented, tested and improved upon, on an ongoing basis.

A Vibrant Community

The challenges brought the small but close-knit permanent community of up to 140 inhabitants even closer together, and expertise was continually brought in to ensure that energy production went smoothly.

As construction of the power plant was concluding and leading into the operations stage, over the following seven-year period from 1906 to 1913 Hydro built a total of 16 houses with 33 separate living quarters.

In addition, a group of five identical multi-family houses for the workers were built where the workers’ cabins had stood before – large, simple, barrack-like dwellings of four housing units and a shared water closet in the basement.

Duplexes and villas were built for the engineers, including an elegant home for the chief engineer built in 1913. This was named the Fougner Villa in honour of the manager, the last of the housing built at Svælgfos, and it marked the end of Hydro’s housing projects at Svælgfos.

Plans for the Future

Sam Eyde had rested all of his vision and ambitions upon success here at Svælgfos – and

the people of Hydro had risen to the occasion. Even now as you stand by the dam at Svælgfos, one still feels this and truly understands why.

The famed Norwegian artist Theodor Kittelsen was commissioned to show the world the power of the people, the industry – and the water that powered a new revolution in hydroelectricity.

Today, even many years later there are still twelve ‘Hydro’ houses at Svælgfos from that period, the majority of these being well-preserved. The importance of this area to the Rjukan-Notodden Industrial Heritage site is unmistakable.

There are plans underway at Svælgfosen to honour this legacy. These plans will bring together the cultural and industrial history as the world begins to rediscover the importance of what occurred here.

Special thanks to NIA for use of the historical photographs used in this article.

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