Swiss Water Management and the Delta Works of the Alps
17 April 2026
Swiss engineers can not only drill tunnels and build railways, but are also canal diggers, dyke builders and excellent water managers.
The Thielle between Nidau and Büren before the Jura water regulation project. The flood of 1817. Bern State Archives
Seeland
Seeland and the big marsh (das Grosse Moor/ le grand marais) is the region in the Three-Lakes-Region (Drei-Seen-Land/le Pays des Trois Lacs), the lakes of Neuchâtel (Neuenburg), Bienne (Biel) and Morat (Murten), and stretches across the cantons of Bern, Freiburg, Solothurn, Waadt and Neuchâtel.
The lakes and rivers
After the last Ice Age (around 12 000 years ago), a lake stretched over 100 kilometres from Yverdon-les-Bains (canton of Vaud) to Solothurn. The rivers Aare, Emme, and Zihl (Thielle in French) crossed this region, causing many floods.
Image: Musée d’Yverdon et région
The water management
From the beginning of the 18th century, engineers devised plans to mitigate this flooding. However, the technical possibilities were still too limited. The Industrial Revolution in the nineteenth century created new opportunities.
Moreover, the new Swiss Confederation of 1848 was authorised to finance cross-border cantonal projects. The regulation of water management concerned the five cantons mentioned above.
A view following the lowering of the water level in Lake Neuchâtel and the remains of Celtic pile-dwelling houses, circa 1890
Image: Amt für Wasser und Abfall (AWA, Kanton Bern).
La Correction des Eaux du Jura/Juragewässerkorrektion
The so-called Jura water correction (La Correction des Eaux du Jura/Juragewässerkorrektion) occurred in two stages.
The engineer Richard La Nicca (1794-1883) developed the first project (1868 to 1891). The Aare was diverted into Lake Biel by digging a canal between Aarberg and Hagneck (1 in the picture). In addition, three other canals were dug: the Canal La Broye (3) between Lake Morat and Lake Neuchâtel, the Canal Zihl (Thielle, 2) between Lake Bienne and Lake Neuchâtel and the Canal Nidau-Büren (4 on the illustration), which regulated the Aare from Büren to Lake Bienne. The Emme was excluded from the project. Figure 5 shows the area of Seeland.
The Aare was the primary source of concern. The river transported more water than the Swiss Rhine. The water levels in the lakes were lowered by several metres due to these projects. It created new agricultural, natural and recreational areas in this region.
Even the island (île St. Peter/St Petersinsel) in the Bielersee/lac de Bienne, where Jean-Jacques Rousseau (1712-1778) lived in 1765, became a peninsula due to a lowering of the water level.
In addition, at the end of the nineteenth century, one of Europe’s first hydroelectric works, the BKW (Bernisch Kraftwerke), was built near Hagneck.
Centrepiece
The new water management system’s focal point was the regulation of the Aare. The water-permeable Dam of Port (Regulierwehr Port/Barrage de régulation) in the Nidau-Büren Canal is the central focus of the project. This major work includes a lock (Schiffsschleusse Port/Écluse de Port), a road connection between Brügg and Port, and, later, a hydroelectric power station (Wasserkraftwerk Brügg/Centrale hydroélectrique de Brügg).
Hagneck Channel. Photo: TES.
However, there were still some floods. The second water correction was carried out between 1962 and 1973. This project included the construction of the Flumenthal hydropower plant on the Aare beyond Solothurn and the expansion, deepening and widening of the Hagneck, Broye, Zihl and Nidau-Büren canals.
The power plants, locks and dams were also modernised at the end of the 20th century. Additionally, a new hydropower plant was constructed in the Nidau-Büren canal to generate electricity.
Nidau-Büren-Kanal
Today, the central regulation of water levels in the three lakes and the Dam of Port is carried out from Bern (Regulierzentrale/Centrale de Régulation). From here, the water levels of the three lakes and the River Aare are monitored.
Today, the region is the most fertile agricultural region and the country’s leading supplier of fruit and vegetables. In addition, several nature reserves have been created on the banks of the lakes, including on the southern shore of Lake Neuchâtel. The area has been developed to suit tourism and its facilities.
Conclusion
The water management of the three lakes and the rivers Aare, Emme and Zihl has been the subject of various projects since 1868. Differing, sometimes conflicting, interests in shipping, fishing, landscape and nature conservation, agriculture and safety for the inhabitants also played a role.
Despite these human interventions, nature proved stronger in the summer of 2021. The floods were not nearly as devastating as they had been before these interventions, and the control mechanisms were effective, but they underscore the need for modesty concerning the power of nature.
This water management has consequences for other areas, such as the Brienz and Thun lakes and the Aare’s further course, which flows into the Rhine at the Swiss town of Koblenz (canton of Aargau).
The Gotthard tunnels are widely known. However, these great ‘Delta Works’ of the Alps deserve attention.
(Source and further information: Besucherzentrum Wasserkraftwerk Hagneck,www.bielerseekraftwerke.ch; www.schlossmuseumnidau.ch)
Nidau, Richard la Nicca (1794-1883)