★★★★★
Très bien, pas cher et accueil très sympathique. Merci, car pour ma première fois en kayak, j'adore. Je le recommande. À la prochaine fois 👍🙂
SPW Station 9434 Membre · Official Data · Updated every 15 min
🌊 Real-Time Water Level and Flow Rate of the Semois
Current flow rate, water level, temperature, and kayak navigation authorization — based on official data from the Public Service of Wallonia.
📡 Live Dashboard · Official SPW Station
Semois Hydrometric Live Dashboard
📡 Measurement station 📍
Last update : 21/05 pm31 20:30
💧 Hydrological data
Flow
11,42
m³/s
Height
0,51
m
Water temp.
11,4
°C
✅ Navigation
Navigation allowed ✅
🌤️ Weather conditions
Air temperature18.9°C
Wind5.62 km/h
Humidity61%
Difficulty score
15/100
Conditionnuageux
🔍 Analysis :
Current flow position on the navigation range
1 m³/sCalmIdealDynamic40+ m³/s
Current flow: 11.42 m³/s — Peaceful
🌤️ Current weather conditions in Vresse-sur-Semois
Water
11.4°C
Water temp
🧊 Cold Water – Risk of Cold Shock (11.4°C)
Below 15°C, capsizing can cause severe thermal shock. A certified life jacket (included in your rate) is mandatory. A neoprene wetsuit is highly recommended.
Below 15°C, capsizing can cause severe thermal shock. A certified life jacket (included in your rate) is mandatory. A neoprene wetsuit is highly recommended.
📊 Reading Guide · 6 flow rate ranges
How to interpret the Semois flow rate?
The Semois is a river with a strictly pluvial regime: its flow rate can triple in less than 6 hours after heavy rain. This guide helps you instantly understand the meaning of each range and adapt your kayaking experience.
| Flow (m³/s) | Navigation Status | Conditions | Recommendation | Recommended Profile |
|---|---|---|---|---|
| < 2.2 | ⛔ Forbidden | Water too low. Rocky bottom exposed. Protection of the riverbed and benthic fauna. | Navigation forbidden by DNF / SPW. | |
| 2.2 – 5 | ⚠️ Calm | Very calm river. Bottom sometimes visible. A few obstacles to avoid. | Experts and initiates only. | |
| 5 – 15← CURRENT | ✅ Ideal | Perfect conditions. Clear water. Steady and manageable current. | All levels · Families · Kids 3+ years. | |
| 15 – 30 | ✅ Good | Good flow. Steady current. Slightly faster routes. | Families and intermediates · Careful beginners. | |
| 30 – 50 | ⚠️ Strong | Strong current. Turbid water. Requires good paddling skills. | Intermediates and sporty · Not rec. for under 8s. | |
| > 50 | ⛔ Flood | Dangerous flood. Unpredictable current. Severe risk of capsizing. | Navigation forbidden – dangerous. |
Source: Walloon Navigation Regulation · SPW Station 9434 Membre · Official range 2.2–50 m³/s
📡 Why monitor the flow rate and not just the status?
The binary status (authorized/forbidden) doesn't capture the nuances. A flow of 3 m³/s is officially authorized but very different from a flow of 12 m³/s in terms of comfort and safety. Our 0-100 difficulty score cross-references flow, water temperature, weather, and humidity for a more accurate assessment of conditions.
The binary status (authorized/forbidden) doesn't capture the nuances. A flow of 3 m³/s is officially authorized but very different from a flow of 12 m³/s in terms of comfort and safety. Our 0-100 difficulty score cross-references flow, water temperature, weather, and humidity for a more accurate assessment of conditions.
🪨 Devonian Schist · Pluvial Regime · Rain Reactivity
Understanding the Semois: Geology and Hydrological Behavior
The Semois is not just any Ardennes river. Its unique geology explains why its flow can vary so rapidly — and why our real-time monitoring is essential.
🪨 Geological Substrate
Devonian Schist + Phyllites
Impermeable rock → rainwater runs off directly into the river instead of infiltrating groundwater. Maximum reactivity to rain events.
No significant groundwater
Unlike the Lesse or the Meuse, the Semois has no natural "buffer". Its flow fluctuates directly with the rainfall in the Ardennes.
Deep meanders (200–350m)
Steep slopes protect from the wind and create a humid microclimate. However, they channel runoff water and amplify flow variations.
Catchment area of ~1,345 km²
The entire Semois catchment area (from its source to the French border) feeds the 9434 Membre station. Rain in Neufchâteau can be measured in Membre 6-12h later.
📊 Official SPW Thresholds
EFR (Extraordinary Flood Rate)
121.8 m³/s
100-year flood. SPW reference value for risk studies.
AMF (Average Monthly Flow)
16.7 m³/s
"Normal" flow of the Semois across all seasons.
EFR Kayak (ban threshold)
50 m³/s
Threshold triggering the navigation ban. ×3 the average monthly flow.
Nature protection threshold (min)
2.2 m³/s
Minimum threshold to preserve the riverbed and fauna. Below: navigation stopped.
📖 Full hydrological analysis →
📅 When to go · Typical flows by season
When to kayak down the Semois? Seasonal Guide
The Semois flow varies significantly by season. This guide helps you choose the optimal period according to your skill level and expectations.
Summer (Jun-Aug)
5–20 m³/sPerfect conditions for everyone. Warm water (16-22°C). Families and beginners welcome. Max wildlife. High season: book in advance.
Autumn (Sep-Oct)
10–35 m³/sSpectacular Ardennes colors. Deer rutting. Highly active beavers. Steadier current but navigable. Less crowded. Exceptional light for photography.
Spring (Apr-May)
15–60 m³/sOften high flows post-rain. Keep an eye on the dashboard! Bank blooming, wildlife nesting. Ideal for sporty paddlers. Check flow the day before.
Winter (Nov-Mar)
20–80+ m³/sWe are open year-round. Silent atmosphere. Cold water (2-8°C): neoprene wetsuit mandatory. Unpredictable flow. Experts only.
⚠️ Walloon Region Regulations · Safety
⚓ 5 golden rules for a safe descent on the Semois
Check the flow before each trip
Check this dashboard or sign up for our email alerts. A suitable flow guarantees a safe and pleasant experience for everyone.
Respect SPW bans
The Walloon Region may ban navigation if the flow is too low (< 2.2 m³/s) or too high (> 50 m³/s). These decisions are legally binding.
Protect Natura 2000 areas
The Semois flows through strict protection zones. No littering, no excessive noise, no landing outside official zones.
Supervise children
Children must be accompanied by an adult. A certified life jacket is mandatory for all ages. For under 8s, prefer the Alle→Vresse route (7 km) with shallow water.
Beware of cold water
Below 12°C, capsizing can cause cold shock in 30 seconds. Mandatory life jacket, neoprene wetsuit recommended between October and May.
❓ Frequently Asked Questions · Semois Water Level · Kayak Navigation
FAQ — Semois Water Level and Flow Rate
What is the current flow rate of the Semois?
The current flow rate of the Semois is 11.42 m³/s (SPW station 9434 Membre, recorded 21/05/2026 at 20h30). Navigation: Authorized ✅. The authorized range is 2.2 to 50 m³/s.
Is kayak navigation on the Semois authorized today?
As of 21/05/2026 at 20h30, navigation is Authorized ✅ (flow rate 11.42 m³/s). Authorization covers hours from 9:30 AM to 8:00 PM. Our system automatically alerts reservations if there is a change.
Why can kayaking on the Semois be forbidden?
Navigation is forbidden if: (1) flow rate < 2.2 m³/s (water too low, protecting the rocky bed and benthic fauna); (2) flow rate > 50 m³/s (dangerous flood). These thresholds are set by the Walloon Region.
What is the best flow rate for kayaking on the Semois?
The ideal flow is between 5 and 15 m³/s: clear water, visible bottom, steady current suitable for all levels. Between 2.2 and 5 m³/s: very calm, ideal for beginners. Between 15 and 30 m³/s: steady current, for sporty paddlers.
How often is this dashboard updated?
Every 15 minutes via official data from the Public Service of Wallonia (station 9434 Membre). You can subscribe to email alerts via the button above to be notified automatically.
What is the water temperature of the Semois?
The water is currently at 11.4°C. Below 12°C, a life jacket + neoprene wetsuit are recommended to prevent cold water shock. Our certified jackets are included in all all-in rates.
Why does the Semois react so quickly to rain?
The Semois rests on an impermeable Devonian schist substrate: rainwater runs off directly into the river without infiltrating aquifers. Its flow can triple in 6 hours after a storm over the catchment area (1,345 km²).
Can you kayak in winter on the Semois?
Yes, we are open all seasons. Winter offers a unique atmosphere, but the flow is often high (20–80 m³/s) and the water is cold (2–8°C). Neoprene wetsuit mandatory. Reserved for experienced kayakers. Always check the dashboard before leaving.
How does the difficulty score work?
Our proprietary algorithm cross-references 5 variables: flow rate (main), water temp (cold shock risk < 10°C), weather conditions (thunderstorm = immediate score of 100), humidity, and wind. Score 0-100: < 40 easy · 40-60 moderate · 60-80 difficult · > 80 dangerous.
What is the current water height of the Semois?
The water level of the Semois is 0.512 m at the reference station (21/05/2026 at 20h30). Below ~0.20 m: rocks exposed, kayaking difficult or impossible. Above 1.50 m: potentially dangerous current.
✅
The Semois is open — Book now
Current flow: 11.42 m³/s — Conditions Ideal conditions. Perfect flow for all levels. Clear water, visible bottom. Families and beginners welcome. From €18 all-in, free shuttle.