The man began a seven kilometre hike along the Murrumbidgee River around 6.30am but became weary during the day.

According to the ACT Ambulance Service, he was carrying only a small amount of water and found the river currents too strong while paddling.

At 3.30pm, the man rang emergency services members who walked almost a kilometre to find him. Paramedics spent nearly 90 minutes monitoring his conditions before the man returned home to his family.

An ACT Ambulance service spokesman said the incident was a reminder for people to carefully plan for hikes and bushwalking.

"It is important that on days of high temperatures the community drink enough water and plan ahead if undertaking strenuous activity," he said.