Water levels in Lake Constance have reached a record low in the Untersee. The Swiss Federal Environment Agency carries out measurements in Berlingen On Wednesday, 7 October, the water level stood at around 394.16 metres above sea level. The previous lowest level recorded there, on 14 January 1949, was 394.31 metres. The current figure is approximately 15 centimetres lower than that. This refers to the water level at this measuring point, not the water depth in a specific harbour.
Shallow harbours are becoming a problem
In the Untersee, a matter of a few centimetres determines whether a pleasure boat can leave or return to its berth. Particularly shallow harbour approaches and moorings are affected. Anyone moored there should not assume that their boat can manoeuvre simply because its draught is comparatively shallow: the propeller and propulsion system also need clearance from the seabed.
As early as the Low water levels in 2022 Boat owners on Lake Untersee had to remove their boats from the water or move them to other harbours. The figures from that time do not reflect the situation in October 2026. However, they do show how quickly a low water level can turn into a real mooring problem.
For upcoming journeys, this means: the Current water level at Lake Constance Check this and ask the harbour authorities about the actual usable depth at the approach and berthing area. The water level reading alone does not answer this question. Our article explains how a water level reading differs from the water depth in front of the boat: Water levels and water levels on waterways.
Scheduled ferries are operating on a limited basis
The consequences extend beyond recreational boating. The Lake Constance Shipping Companies have their Untersee routes between Radolfzell, Iznang, Mannenbach and Reichenau has been suspended until further notice due to low water levels. The Swiss Untersee and Rhine Shipping Company According to its revised timetable, it will operate between Gottlieben and Öhningen from 5 to 18 October. Among others, its vessels are currently unable to call at Konstanz, Kreuzlingen, Mammern and Wangen.
There is no sign of the situation easing any time soon. The official Report on the water level of Lake Constance describes the water level as extremely low for this time of year and, in line with the natural annual cycle, expects levels to fall further in the coming weeks. It is not possible to make a general assessment of the extent to which individual harbour basins remain navigable. Before setting sail, it is important to check the information for the specific berth.
Further articles on this topic
Our report on how low water levels have previously restricted the use of the harbour describes Problems at the Lake Constance ports in the summer of 2022.
Our guide explains why a water level is not the same as the available depth: Water levels and water depth.
Book recommendation
Lake Constance provides information on Obersee, Untersee and Überlinger See for sailors and motorboat enthusiasts. Harbour maps, aerial photographs and navigation advice help you to plan your trip and identify possible alternative harbours. Particularly when water levels are low, it is important to distinguish between route planning and current navigability: the information provided in the sailing guide is no substitute for checking the latest water levels or consulting the harbour master regarding usable depths.
What is the situation like at your harbour on the Untersee: are the access routes and moorings still usable, or have you already had to move your motorboat? Please share your observations in the comments.
Ursula Meer
Redakteurin Panorama und Reise
