River waves · Case studies

Case study Leinewelle Hanover: 2.5 million without public money

The enercity Leinewelle lies in the middle of the state capital, behind the Leineschloss and under the Schlossbrücke. It is the counter-model to Nuremberg: the same technology, but not a single euro of public money. And it shows what a permitting procedure looks like when an angling club sues. Profile and location: Leinewelle in the wave directory.

At a glance

Timeline

The idea dates from 2013. In 2015 the club moved the site around 200 metres downstream under the Schlossbrücke, to the narrowest point of the Leine, and opted for a fully lowerable installation. In 2018 the City of Hanover concluded a licence agreement (Gestattungsvertrag) with the club, unanimously in the committees. In 2019 the Hanover Region issued the water-law permit – a planning approval procedure (Planfeststellung) was not necessary. The Hanover angling club filed a lawsuit against it; the administrative court dismissed the suit in January 2021, and in April 2021 both sides reached an out-of-court settlement. Ground-breaking was on 25 June 2021. In November 2021 a construction stop followed: the clay subsoil required a reinforced foundation. In August 2022 the first wave body was lifted in, in October 2022 trial operation ran, on 28 April 2023 the wave was opened – with the German Championships in Rapid Surfing on the same weekend.

Ten years from idea to opening, four years from permit to opening.

Technology

The Leinewelle uses the Dreamwave technology like Nuremberg: steel wave bodies with a patented hydraulic ramp whose angle can be set continuously via app. A fish pass is integrated; the control system runs on green electricity. Before construction, a 1:7 scale model was tested in the flume of the University of Innsbruck. In summer two modules run (around 6 metres wide), in winter three (around 9 metres) – the wave is adapted to the discharge, not the other way round.

The subsoil was the expensive surprise: clay instead of load-bearing ground, hence the construction stop and foundation reinforcement. And the flood around Christmas 2023 washed so much sand into the installation that it stood still until March 2024; draining it with a needle weir and pumps and installing pneumatic flushing flaps cost an unplanned 40,000 euros or so.

Costs and funding

The cost estimate of 1.2 to 1.4 million euros (2021) ended up at 2.4 to 2.5 million. The club has borne everything itself: planning, permits, construction and operation – that is what the licence agreement with the city says, and the city contributes at most to a monitoring device. Around two million euros came together in ten years through donations and sponsorship. Main sponsor and namesake is the energy supplier enercity, joined by Sparkasse Hannover, the construction company Gundlach and the university sports club. Operation is non-commercial and is funded by sponsors, membership fees and donations. → Costs and funding

Permits and procedure

The responsible body was the Hanover Region as water authority; there was a preliminary environmental impact screening with expert reports, and the city acted as landowner through the licence agreement. The angling club with around 5,600 members sued on account of protected species such as bullhead, spined loach and river lamprey. The administrative court considered the section to be limited for fish by the Leine weir anyway and held the individually designed eco-pass with a monitoring requirement to be sufficient. The subsequent settlement: both sides jointly campaign for an additional fish pass at the upper weir. The opponent became a partner.

The licence agreement also governs operation: a term of 15 years with an option to extend, seasonal operating hours, no music and no lighting, operation stops during combined sewer overflows, an obligation to dismantle after the contract ends. → Ecology and permits

Operation

Surfing takes place all year round in one-hour slots with ten people, supervised by two volunteer "wavemasters". Guests pay 20 euros per slot, members 240 euros a year including 24 slots, then 10 euros for each further slot; trainees, students and minors get a discount. The club grew from around 200 members at the opening to over 400 in spring 2024, with more than 2,400 surfing hours in the first year; in 2026 the club speaks of over 500 members and guests. At "Die Finals 2026" in July the Leinewelle was the venue for the German Championships in Rapid Surfing with around 9,000 to 10,000 spectators per day – the attendance record for a surfing event in Germany. → Rapid surfing

What Winterbach can learn from this

Hanover proves that a river wave can be built without public money – if a large sponsor buys the naming rights, a savings bank and a construction company come on board and the club holds out for ten years. For Winterbach the second lesson is more important: the settlement with the angling club shows that the holder of the fishing rights belongs at the table early on, not first in court. And the licence agreement is a blueprint for how municipality and club can settle responsibility, operating hours and dismantling. The third lesson is the subsoil: what lies beneath the water determines the costs – a ground investigation belongs in every feasibility study.

Frequently asked questions

Who paid for the Leinewelle?

The club Leinewelle e.V. – with around two million euros in donations and sponsorship over ten years, above all from enercity, Sparkasse Hannover and Gundlach. No public money was involved.

Why did the angling club sue – and how did it end?

Because of protected fish species in the section. The administrative court dismissed the suit in 2021, after which the club and the anglers reached an out-of-court settlement and have since campaigned jointly for an additional fish pass.

Does the Leinewelle run all year round?

Yes, depending on weather and water level, with two modules in summer and three in winter. After the 2023/24 flood, however, it stood still for three months because of sand deposits.

Sources: Leinewelle e.V., FAQ, "Der Verein", "Surfen", notice 07.03.2024 (enercity-leinewelle.de) · State Capital Hanover, council document 1549/2018 · Hanover Administrative Court, press release 12.01.2021 · Weser-Kurier, 17.04.2021 · enercity, press releases 25.06.2021 and 28.04.2023 · State Capital Hanover, press release 12.08.2022 · Surfers Mag, August 2022 · t-online, 28.04.2023 · Xylem, case study Leinewelle · hannover-entdecken.de, July 2026 (Finals) · Wikipedia, "Leinewelle"

Last updated: 15 October 2026 · Initiative Remswelle