The verdict in 30 seconds
You can go kayaking on the Lesse between 1.5 and 52 m³/s. Below that, navigation is forbidden; above it, the river is in flood and navigation is forbidden too. In between, how good the trip is depends mostly on where the reading falls in the table below.
Reading the river flow, band by band
River flow is the volume of water passing the station each second. It combines both depth and current speed, which makes it a better guide than water level alone.
| Flow (m³/s) | Conditions | Navigation | Key point |
|---|---|---|---|
| 0 to 1.5 | Too low | Forbidden | The rocky riverbed and aquatic life are protected. |
| 1.5 to 6 | Very calm | Allowed, take care | Rocky bottom sometimes visible; better for experienced paddlers. |
| 6 to 25 | Ideal conditions | Allowed | Crystal-clear water, accessible to everyone, families included. |
| 25 to 45 | Steady current | Allowed | Faster trip; beginners should stay alert. |
| 45 to 52 | Strong current | Allowed, take care | Powerful; not recommended for complete beginners. |
| Over 52 | Flood | Forbidden | Flood flow, dangerous for people. |
The station and the stretch concerned
The reference flow comes from SPW hydrometric station 8221, at Gendron. The regulated stretch runs from Gendron to Anseremme, where the Lesse flows into the Meuse. The official status is set stretch by stretch: one section can be closed for lack of water upstream while another stays open.
The decision is based on the average flow over the last 72 hours compared with the minimum threshold, not on a single measurement. The reading at the top of the page shows you this status; it is checked regularly against the SPW.
What the regulations say
- The Walloon Government decree of 19 March 2009 sets the minimum and maximum flows (Annex 2) and the signage for put-in points (Annex 3).
- The “navigation allowed” or “forbidden” status follows from these thresholds (Article 6).
- The flag colours sometimes used to summarise conditions have no legal value: only the thresholds and the put-in signage do.
For an overview of the other rivers, see the paddling rules in Wallonia page.
Safety by water level and weather
- Low flow: expect shallow stretches and some portaging or scraping over stones. Allow extra time.
- Steady or strong flow: the current shortens the trip but leaves less time to react. Keep your group close together.
- Cool air or cold water: bring a windproof jacket, a fleece and a change of clothes kept dry in a waterproof barrel. A capsize chills you fast.
- Rain or gusts: a waterproof jacket and a waterproof bag are a must; a headwind makes paddling more tiring.
- Fog: stay together and spot obstacles earlier.
After heavy rain in the catchment, the flow can pass the upper limit even under a clear sky: check again on the morning you leave.
Finishing your preparation
To plan your day, see the Lesse route down to Dinant and the prices. At the finish, the Meuse follows a different logic, that of a navigable river. To compare with another river, open the Semois.