Most hydration advice for hikers is written for overseas conditions where water sources are reasonably reliable and temperatures are moderate. On Australian bush tracks, particularly in summer, neither of those things is consistently true. Getting hydration wrong on a remote track can turn a good day into a serious one quickly.
How Much to Carry
500ml per hour of walking is the figure you see most often, and it is a reasonable starting point for mild conditions. In summer heat on exposed terrain, particularly in western NSW or in the Blue Mountains in February, that number needs to go up. A hot day with significant climbing in direct sun can push requirements well beyond a litre per hour.
Do Not Rely on Track Water Sources
Many Australian bush tracks that are marked with water sources on the map are seasonal. They run during and after wet periods and dry up in summer. Check recent trip reports for the specific track before relying on a marked source. The default position should always be to carry your full water supply rather than plan on a refill that may not be there.
Treating Water from Natural Sources
If you are on a multi-day walk or planning on using natural sources, carry a water filter or purification tablets. Giardia is present in Australian waterways including mountain streams. Boiling water works if you have the fuel and the time, but a small filter is lighter and faster for day-to-day use on the trail.
Signs of Dehydration to Watch For
- Dark urine or reduced urination
- Headache that develops on the track
- Feeling more tired than the terrain warrants
- Light-headedness or nausea on rest stops
- Dry mouth and reduced saliva
Pre-Hydrate
Arriving at the trailhead already slightly dehydrated is more common than most people realise, particularly after a long drive in the car. Drink water the night before a big walk and have a proper amount in the morning before you start. By the time you feel thirsty on the trail, you are already behind.
