This short 1 kilometre return walk, which is wheelchair friendly, starts at the Cotter Bend car park (a short trek from the camping ground– see my Cotter Reserve review) and meanders along the bubbling river, shaded by native and exotic trees to the base of the Cotter Dam.
Along the trail, a combination of sealed paths and boardwalk, are numerous informative boards providing those interested with more detail on the history of the area, the Dam and the flora and fauna found in the area.
Being only 1km long you could complete this walk in less than 15 minutes but give yourself up to an hour, or longer if you want to stop for a picnic, to better enjoy the walk and have a longer look at the dam when you get there.
Lest you wonder why the Dam viewing platform (pictured below) is a seated amphitheatre arrangement, it’s because it was built just prior to the construction of the enlarged dam to let visitors sit and watch the dam wall being built.
If you lower your eyes from the Dam to just below the viewing platform you will see the remains of an old trout hatchery dating from the 1930s. Interestingly, some of the fish used to stock Lake Burley Griffin, in Canberra, when it was constructed in the 1960s came from this hatchery which closed in 1966.
As you ponder the Dam and enjoy the river remember that the existence of this river was a major factor in determining the location of Australia’s capital city in the early 1900s. In a 1907 report the Acting Chief Engineer of New South Wales stated that:
“It is impossible to imagine a catchment from which a purer supply of water could be obtained. The water is soft, and even in times of fresh (after flood), is clear and of good colour…There are few cities in the world where such a magnificent supply of pure water is available”
It is hardly surprising that not one but three dams have been built on the Cotter River to capture this pure water for good citizens of Canberra. I, for one, can vouch for its taste, as being amongst the best I have tasted anywhere in the world.
Canberra has four main sources of water and consequentially four dams. As indicated earlier three of these the Cotter, Bendora (1961) and Corin Dams (1969) are on the Cotter River, itself little more than a mountain stream, which flows through the western part of Namadgi National Park. Bendora and Corin Dams are located within the National Park while the Cotter Dam, the lowest of the three at 550 metres above sea level, is outside the Park and only 22 kilometres from the centre of Canberra.
The original Cotter Dam, a 30 metre concrete dam, was constructed in 1915 (raised in 1951) and served as Canberra’s primary source of water until the 1960s when it was decommissioned following the construction of the other two Dams further up the river. Getting water from Cotter was expensive as it had to be pumped up to the Mt Stromlo Water Treatment Plant, for on distribution to Canberra residents, whereas water from the higher up Corin and Bendora dams was (and is) delivered by gravity feed and was also of higher quality.
In 1979 an additional dam, the 119GL Googong Dam, was constructed to meet an increasing demand for water in the Canberra area, rather then recommission the then tiny 4GL Cotter Dam. Building the Googong Dam on the Queanbeyan River also mitigated the risk of some disaster befalling the Cotter River and making all three Dams on it inoperable. Today, Canberra sources around 43% of its water from the Googong Dam.
Severe droughts in the early to mid 2000s, coupled with contamination of water in the Corin Dam as a result of catastrophic fires in much of the catchment area in 2003, lead to severe water use restrictions in Canberra which lasted almost a decade.
To alleviate the risk of future water shortages, the government introduced a range of measures including the recommissioning of, and the enlargement of, the Cotter Dam. A new dam wall, the one you see today, completed in 2014. It is located 100 metres down river from the original dam wall, is 80 metres high and increased the storage capacity of the Dam from 4GL to 76GL.
In addition to recommissioning the dam, the historic Cotter Pumping Station (below), which you pass just before you take the bridge across the Murrumbidgee River as you enter the Cotter area from Canberra was reopened.
The Dam wall is easily seen from the viewing point at the end Cotter Dam Discovery Trail A closer up look (though hardly needed unless you enjoy the scramble) can be had if you follow a track to your left facing the Dam wall at the closest point you can get to it. The catchment area/reservoir (below) is best seen from the lookout at the end of the Cotter Catchment Lookout Track (2.8kms return walk) accessed from the Brindabella Road a couple of kilometres drive from the Cotter Reserve. See my separate review on the Cotter Catchment Lookout Track from which the last three pictures in this review were taken.
Note: Access onto the Cotter Dam wall is not permitted and please, for my sake, no peeing in the reservoir’s catchment area!
Address: Cotter Road, Stromlo
Directions: 22km west of Canberra City centre.