When is a river too dangerous to cross?

As a general rule, do not cross if the water is above knee depth with any significant current, or if the force of water (depth x speed) makes it hard to maintain balance. Cold water (below 10°C) adds significant danger due to cold shock and rapid heat loss.

How do I estimate river speed without equipment?

Throw a stick into the current and time how long it takes to travel a known distance. Walking pace is about 1.2 m/s. If the stick moves faster than you can walk, the current is strong. If you cannot keep up, it is likely too fast to cross safely.

What is the safest technique for river crossing?

Face upstream, use trekking poles for a third point of contact, move sideways across the current. Unbuckle your pack hip belt so you can ditch it if you fall. Cross at the widest point (usually shallowest). In groups, link arms with the strongest person upstream.

What are the risks of cold water immersion?

Water below 15°C triggers the cold shock response: gasping, hyperventilation and panic within the first 1-2 minutes. Below 10°C, you may lose grip strength within 3-5 minutes. Below 5°C, incapacitation can occur within minutes. Always minimise time in cold water.

CampCalcs

River Crossing Calculator — Safety Assessment

Assess river crossing safety from depth, current speed and water temperature.

Water Depth

Estimated depth at crossing point

Current Speed

Speed of water flow (walking pace ~1.2 m/s)

Water Temperature

Approximate water temperature

Riverbed Type

Surface underfoot condition

How We Calculate This

The calculator assesses crossing risk from four factors: depth, current speed, water temperature and riverbed condition.

Risk factors

Force factor = Depth x Speed x Riverbed multiplier
Depth risk: Below knee (low), knee-to-thigh (moderate), thigh-to-waist (high), above waist (extreme)
Speed risk: Under 0.5 m/s (low), 0.5-1.0 (moderate), 1.0-1.5 (high), 1.5+ (extreme)
Cold shock: Added risk below 10\u00B0C water temperature

The overall score is the worst-case of depth, speed and force, with a penalty for cold water.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Always verify conditions and use proper safety equipment outdoors.