The NCC has approved a $1.3-million project to install rails along a 2.4 kilometre stretch of the Rideau Canal.
There is no barrier along the multi-use path on the Colonel By side from Dow's Lake to the Hog's Back Bridge.
There have been instances in the past of cyclists falling in.
One suffered critical injuries in April 2015.
A month later, two bystanders rescued another who went over the side.
The installation is set to begin in October and finish in December.