Two questions before you go
On the Ourthe, you need to check two separate things: is the flow within range, and does the SPW allow navigation? The two do not always match. Flow can be above the official minimum of 2.5 m³/s while the river stays closed under a temporary ban, sometimes with no reason published. It reopens as soon as the ban is lifted.
The live reading shows the official status; rely on it rather than on the flow figure alone.
The stretch concerned
The rules apply to the Ourthe downstream of the Barvaux movable weir, as far as Comblain-au-Pont. The measurement comes from SPW hydrometric station 5921 at Tabreux, updated about every 15 minutes. The legal framework is the Walloon Government decree of 19 March 2009 (Article 6).
- Official minimum: 2.5 m³/s, assessed on a 72-hour average.
- Maximum: 65 m³/s.
The flow bands
| Flow (m³/s) | Level | In practice |
|---|---|---|
| Under 2.5 | Too low | Navigation forbidden to protect the rocky riverbed and biodiversity. |
| 2.5 to 10 | Very calm | Rocky bottom sometimes visible; for experienced paddlers. The SPW status of the day prevails. |
| 10 to 40 | Ideal | Clear water, suits all levels, families and beginners included. |
| 40 to 65 | Steady current | Faster, more dynamic trip; beginners should stay alert. |
| Over 65 | Flood | Navigation forbidden. |
Reading the forecasts correctly
The flow estimates for the coming days are projections calculated from the weather and the river’s history. They do not replace the SPW decision, which is published every day. A booking should therefore allow for both: have a fallback date in case the official status changes.
Equipment by season
Cold water catches people out in autumn and early spring. To limit the risk if you capsize: life jacket fastened, a fleece and a change of clothes kept dry in a waterproof barrel, and a windproof jacket. Gusty wind makes the trip more tiring, and rain calls for a waterproof jacket and a waterproof bag.
Why a 72-hour average
The SPW does not judge a snapshot. It looks at the average of the last three days, which smooths out rain peaks and night-time lows. The result can be surprising: the current flow is sometimes well above the official average, as after a storm, without the status changing straight away. Always compare the two values in the reading, the current flow and the average used for the threshold.
The aim of these restrictions is to protect the rocky riverbed and the river’s biodiversity. Respecting them also protects your equipment.
Going further
You will find the common safety rules on the paddling rules page. If the Ourthe is closed, compare with the Semois or the Amblève.