Hydropower: More Than Just Electricity

When Silvan Frei, Head of Infrastructure at the Wildegg-Brugg Power Plant, gets into his pickup truck, his day begins away from the turbines. Much of what seems to go without saying is the result of his work—from safe paths to a healthy forest. After all, the mission of hydropower extends far beyond electricity production.

The Wildegg-Brugg power plant is the most powerful hydropower plant on the Aare. It supplies an average of around 300 million kilowatt-hours of clean electricity per year—enough for approximately 55,000 households. The concession area stretches 9.35 kilometers from Wildegg to the railway bridge between Umiken and Brugg and includes parts of the Aargau Floodplain Protection Park. The species-rich floodplain forest is of national importance.

This local recreation area attracts numerous joggers, cyclists, walkers, and nature lovers. People come here to swim, row, picnic, and even party. To make this possible, regular maintenance of the trails, rest areas, and facilities is required behind the scenes, along with measures for nature conservation and flood protection.

“When people think of a power plant, they usually just think of turbines and electricity production. But our mission goes far beyond that,” says Operations Manager Manuel Häfeli. In addition to Wildegg-Brugg, he is also responsible for the operational management of the Rüchlig, Windisch, and Augst hydroelectric power plants. Every plot within the perimeter must be maintained in accordance with the concession requirements of the respective plant. Many people only realize how much work goes into it when it’s not done—for example, when heavy rain leaves large potholes on forest roads. The occasional complaint from a cyclist who has to slow down is just part of the job.

Local businesses benefit

In total, the four plants employ 35 people, including apprentices. This summer, another apprentice will join the Infrastructure department and begin his three-year training as a maintenance technician. Silvan Frei will take him under his wing. The trained forester and agricultural machinery mechanic heads the department. He spends about 80 percent of his working time outdoors on site—where power plant operations, nature conservation, safety, and local recreation intersect. 

Frei grew up in the region and knows the people, the communities, and the businesses. This regional connection has practical value. When a path is blocked after a storm, a tree needs to be secured, or personnel and machinery are urgently needed during flooding, short distances are crucial. Close communication with authorities is equally important when measures need to be coordinated, permits clarified, or priorities set. In addition, the power plant relies on local providers whenever possible—for example, for vehicles, machinery, forestry services, or technical work.

The beaver as builder—and challenge

Frei climbs into the pickup truck. There is much to do. Since early morning, his employees have been cutting back grass and shrubs along the access road to the powerhouse near Villnachern to keep the road clear so vehicles can pass safely. “Without regular maintenance, nature quickly reclaims everything,” Frei sums it up.

Upstream, near Schinznach-Bad, a dam on the right bank of the Aare protects the residential and commercial area. It lies significantly lower than the dammed-up river. Behind the dam runs a small canal. It serves a crucial function: it collects water that might seep through the dam, thereby indicating whether the structure is sufficiently watertight and the settlements are protected. But it is precisely in this canal that beavers particularly like to build. Using wood and mud, the rodent dams up the water. While its architecture is impressive, Frei explains: “If its structures block the canal, we can no longer reliably assess the water level.” That is why, despite the protected status of this species—once extinct throughout Switzerland—beaver dams may be periodically removed here with cantonal authorization.

Near Biberstein, Frei spots a tree that has been severely gnawed. But to the professional, it’s clear: the paths and infrastructure are not yet at risk. The tree will remain standing for now. However, other trunks and branches must be removed. The entire infrastructure team is on site for this, complete with a tractor, trailer, and hydraulic lift arm. The work is not without risk. The men work with focus—their own safety matters too.

Fighting Japanese knotweed & Co.

The next “work site” is less obvious but crucial for the ecosystem: invasive neophytes. “The battle against introduced species like ragwort or Japanese knotweed is the major ongoing issue,” explains Frei. The plants must be pulled out by hand, root by root, and disposed of. This is labor-intensive and ties up staff. “We’re already gearing up for the next operation so we can catch the plants before they go to seed,” says Frei.

Maintenance work generally follows the seasons. Preparations for the summer are currently underway. “For example, we repair the warning signs for boats and water sports enthusiasts, or clean and clear them so they are clearly visible in accordance with concession requirements. Or we grade paths and small roads,” he explains. In the summer, large areas are mowed. In addition, he and his staff at the weir ensure that recreational boats can cross safely and maintain the fish ladder so that fish can migrate. The team also regularly clears away driftwood as a precaution—that is, before logs become wedged or pose a risk during high water. In the winter, the focus is on logging: Forest areas are thinned and secured—always in consultation with the authorities. 

Educate, inform, foster understanding

Near Schinznach-Bad, right next to a popular rest area with a view of the weir, Frei points out one of the bee hotels. It offers native wild bees a variety of nesting structures. An information board explains: “Pollinators are indispensable to us. Without them, we would have to do without a third of our food. In addition, around 80 percent of wild plants depend on pollination by bees. They are therefore crucial for a healthy, stable ecosystem. However, more than half of the over 600 wild bee species in Switzerland are threatened.” The fact that a power plant creates and maintains such structures shows just how broad and important this mission has become today.

A few steps further on, where a striking oak tree once stood, a sign explains that the tree had to be removed for safety reasons. It was infested with fungi. Large, dry branches had already fallen onto the road. It comes as no surprise that walkers react sensitively to such interventions. This makes education all the more important.

“We carefully assess such interventions and explain to the public why we must act as we do,” he emphasizes. In the meantime, a new oak tree is already growing, and it too is expected to once again define the landscape one day.