🌊 Water level & navigability
Can you kayak on the Semois today?
Navigation on the Semois is currently forbidden. Measured discharge: 0.8 m³/s, height: 0.13 m (reading from 29/09/2026 à 17:00). Navigable threshold: 2.2 to 50.0 m³/s (station SPW 9434 Membre). Always check the live indicator just before setting off, as the discharge can change quickly.
What is the water level of the Semois right now?
The current level of the Semois is 0.13 m for a discharge of 0.8 m³/s, water temperature: 14.2°C.
What is the official navigability threshold for the Semois?
The Semois is officially navigable between
2.2 and 50.0 m³/s, measured at station SPW 9434 Membre. These thresholds are based on the hydrometric network data of the Service Public de Wallonie (SPW) and regional waterway navigation regulations. Full detail on
our reference page for navigable flow rates in Wallonia (FR).
Why can navigation be forbidden even in good weather?
A river's level depends on rain that fell upstream, sometimes days earlier and dozens of kilometres away. the Semois can therefore be in flood under a blue sky. Only the discharge actually measured at the station is authoritative, never the look of the sky.
Can I be alerted when navigation becomes possible again?
Yes. The
“Alert me” button, available on the site's water level pages, signs you up for an email notification as soon as the navigation status of the Semois changes.
See the Semois's live water level.
🎒 Preparing your descent
What is the best time to kayak on the Semois?
The best period depends on discharge, weather and regulations. Spring and autumn often offer generous discharge; summer is the busiest and can see the level drop during dry spells. The best habit is always to check the discharge on the day itself.
Can you kayak on the Semois after heavy rain?
Heavy rain can quickly raise the discharge. This can temporarily improve conditions if the level was too low, but a large rise can also make the current dangerous. Check the discharge and any restrictions before setting off.
Can you kayak on the Semois when it's raining?
Light rain doesn't prevent a descent. However, a thunderstorm, heavy rainfall or a rapid rise in water level can make navigation dangerous. In case of a storm, take shelter and follow safety instructions.
What should I do if the water level changes during my descent on the Semois?
If you notice a rapid rise in the current, a flood, or a significant deterioration of conditions, reach the bank as soon as possible in a safe area and get out of the water. Do not try to continue your route at all costs.
🛟 Safety
Do you need to know how to swim to kayak on the Semois?
Knowing how to swim is strongly recommended. Wearing a suitable buoyancy aid remains essential, but it does not replace swimming skills and basic safety rules.
Is a life jacket mandatory?
Always wear a suitable, properly fitted buoyancy aid. It is provided with every rental. Check with the operator which equipment is provided and the rules that apply to your chosen route.
What is the minimum age to kayak on the Semois?
The minimum age depends on the route, the day's discharge, weather conditions and the operator's rules. Children must be supervised at all times by a responsible adult, in a suitable two-seater or family kayak.
Do you need a wetsuit to paddle on the Semois?
This mainly depends on water temperature, weather, season and the risk of falling in. The colder the water, the more important a suitable wetsuit becomes. Check the temperature shown on the dashboard before setting off.
What should you do if you capsize (fall in the water) on the Semois?
Stay calm, stay with your boat if possible and head to a safe bank. Never try to fight against a powerful current.
🗺️ Route
Which kayak route should you choose on the Semois?
The choice depends on your level, the desired duration, your physical condition and the day's discharge. Short, calm routes suit beginners and families better, while longer routes demand more endurance.
How long does a kayak descent on the Semois take?
Duration depends on the chosen route, the discharge, the wind, breaks and the participants' level. Times shown on the site are therefore estimates, not guaranteed schedules.
Can you stop during a descent on the Semois?
Stopping options depend on the route and authorised zones. Respect access points, private property, protected areas and any landing bans.
📅 Booking & conditions
What happens if navigation is forbidden on the day of my booking?
Contact the operator you booked with to find out the options for postponement, cancellation or refund: the exact conditions depend on the specific booking.
Can you book if the water level is currently too low?
Yes, you can check availability for a future date, but a booking does not guarantee navigation conditions: the actual level must always be checked before departure.
When should you check the water level of the Semois before setting off?
Ideally the day before to plan your visit, then again on the morning itself or just before getting on the water. In unstable weather or heavy rain, check conditions regularly.
🌿 Environment
Why should you respect navigation restrictions on the Semois?
Restrictions are not only about kayakers' safety: they also help preserve the riverbed, aquatic habitats and sensitive natural areas.
Can you land anywhere along the Semois?
No. Only use authorised access and landing areas, and respect private property as well as protected natural areas.
How can you kayak without damaging the Semois?
Leave no litter, avoid touching or moving stones and vegetation, respect sensitive areas and limit noise. Best practice is to leave the river in the same state you found it.
📊 Data & reliability
Where does the discharge data shown on this page come from?
The hydrological data shown is based on information from the Service Public de Wallonie (SPW) measuring stations, supplemented where indicated by weather data and our own forecasting calculations.
Can I use this page as my only source to decide whether to paddle?
No. This page is an information and decision-support tool. Also check any official restrictions, the weather, local conditions and the instructions of the operator or competent authorities before any outing.
Why can the discharge shown here differ from what's shown elsewhere?
Services may use different stations, different measurement times or different calculation methods. Always check the station, the measurement time and the source before comparing two values.
🚨 In case of emergency
What should I do if I fall in the water on the Semois?
Keep your life jacket on, stay away from obstacles and try to reach a safe area. If you cannot get out of the water or are injured, contact emergency services immediately.
What should I do in case of a sudden flood on the Semois?
Get out of the water as soon as it can be done safely and move away from the riverbed. Never try to cross a flooded current, and follow the authorities' instructions.
What number should you call in an emergency in Belgium?
Dial 112, Belgium's single emergency number for any intervention by rescue services (police, fire brigade, ambulance).