River waves · building, running, surfing

Permitting a river wave: water law, ecology, floods

A wave in a river is an intervention in a watercourse. For that, Germany has a clear procedure – and clear questions that every initiative has to answer. Those who answer them early save years. Those who ignore them fail: not because of politics, but because of the water.

Which permit?

Converting a weir or installing a ramp is a watercourse modification (Gewässerausbau) within the meaning of the Federal Water Act (§ 67 WHG): a substantial reshaping of a watercourse or its banks. Under § 68 WHG, a watercourse modification requires a planning approval procedure (Planfeststellung) by the water authority – or, if no environmental impact assessment is needed and no significant effects are to be expected, the simpler plan permit (Plangenehmigung). The competent authority is the lower water authority at the district office (Landratsamt); in Baden-Württemberg, for larger projects, the Regional Council (Regierungspräsidium).

In the procedure, all affected interests are consulted: flood protection, river ecology, fisheries, nature conservation, heritage protection, neighbouring landowners. The authority does not decide on sympathy but on expert reports. That is why the feasibility study with a hydraulic proof is the entry ticket, not the list of signatures. → Feasibility study

Water Framework Directive and fish passage

The EU Water Framework Directive (WFD) obliges the member states to bring rivers into good ecological status. A core point is passability: fish and small organisms must be able to pass transverse structures such as weirs. A wave conversion must not worsen fish passage; how this is ensured in the individual case is clarified by the procedure. Nuremberg built the Fuchslochwelle this way: channel parallel to the Pegnitz, wave in the channel, fish pass on the river. Pforzheim placed the wave in an existing channel (Metzelgraben), the river itself remained untouched; the installation can also be lowered completely, so that at rest it hardly obstructs the discharge.

Flood protection

No structure in the river may worsen the flood discharge. The solution of the modern waves is adjustability: Nuremberg's ramp modules, Hanover's hydraulically controlled weir and Pforzheim's hydraulic cylinders move the installation out of the water when the water level rises. The discharge cross-section is then the same as before construction. The hydraulic proof for this belongs in the feasibility study.

Water quality – the lesson from Stuttgart

The Neckarwelle in Stuttgart-Untertürkheim had a feasibility study, a club and political support. The city nevertheless rejected it in 2019: the Neckar is contaminated with pathogens, and anyone who goes under after a fall and swallows water endangers their health. The authority classed this as a knock-out criterion. The lesson for every project: water quality is not a footnote but the first question. Measured values (E. coli, enterococci) at the wave site over a season, discharges upstream and stormwater overflows belong on the table early.

Further interests

Nature conservation. If the site lies in a protected area (Habitats Directive site, landscape protection area), compatibility assessments are added. Fisheries. The holder of the fishing rights is a party to the procedure and often a good early contact. Noise and traffic. A wave roars like a weir; operating hours and access routes are part of the operating concept. Safety. Run-out zone without obstacles, shutdown during floods, operating rules.

How long does it take?

Nuremberg: idea 2011, club 2012, planning from 2013, building permit 2017, opening 2022 – eleven years. Hanover: planning from 2013, start of construction 2021, opening 2023 – ten years. Pforzheim: vision 2014, permit 2018, operation 2021 – seven years. Anyone who wants a river wave plans in years, not in seasons.

Frequently asked questions

Which permit does a river wave need?

Converting a weir or installing a ramp is a watercourse modification under § 67 of the Federal Water Act. It requires a planning approval procedure (Planfeststellung) or, if no environmental impact assessment is needed, a plan permit (Plangenehmigung) from the water authority. Hanover managed with a water-law permit from the Region, Pforzheim with a permit from the municipal environmental office.

How long does the permitting procedure take?

Nuremberg needed four years from the start of planning in 2013 to the permit in 2017, Hanover six years from the idea in 2013 to the permit in 2019 including the licence agreement. With preparation, expert reports and consultation, one should reckon in years.

Can a river wave fail because of water quality?

Yes. The Neckarwelle in Stuttgart was not approved in 2019 because the Neckar is contaminated with pathogens. Measured values at the wave site over a season therefore belong on the table early.

Who has to be involved in the procedure?

The water authority conducts the procedure; nature conservation, fisheries, flood protection, heritage protection and neighbouring landowners are consulted. The holder of the fishing rights is an early contact – in Hanover there was a lawsuit and afterwards a settlement.

Sources: Federal Water Act (Wasserhaushaltsgesetz) §§ 67, 68 (gesetze-im-internet.de) · Stuttgarter Zeitung, March 2019, „Aus für die Neckarwelle“ (The end of the Neckarwelle) · Nürnberger Dauerwelle e.V., history and FAQ · blackforestwave e.V., „Welle“ · Wikipedia, „Leinewelle“ · infranken.de, 25.03.2022

Last updated: 15 October 2026 · Initiative Remswelle