What we're doing
Enlarged Cotter Dam
With droughts tipped to be longer, drier and more frequent ACTEW Corporation is working to increase the ACT region’s sources of water. The Enlarged Cotter Dam project is a key component in ACTEW’s long term plan to ensure water security.
What is the project?
The Enlarged Cotter Dam project involves building a new dam downstream of the existing one to increase the Cotter reservoir capacity from the current 4 gigalitres (GL) to around 78 GL – almost 20 times its current size.
ACTEW Corporation, working with ActewAGL, has formed an alliance with GHD, Abigroup and John Holland to design and construct the dam.
Why is it needed?
The Enlarged Cotter Dam forms part of ACTEW’s continued response to ensuring a secure water supply for the ACT and to address drought, climate change and variability.
Watch July 2010 construction activity at the Enlarged Cotter Dam site - 21.2MB
What’s happening at the moment?
Since the commencement of works in late 2009 we have erected site fences, signage, site offices and established a temporary road network. We’ve installed water diversion piping at the new dam site, established an onsite quarry and are working to install a batch plant which will make the concrete mix for the dam.
We have also erected an onsite crushing plant that will prepare rock from the onsite quarry for use in the concrete mix.
What effects will the new dam have on the environment?
One of the main advantages of the Enlarged Cotter Dam is that it will have relatively minimal impact on the environment. This is because it will be constructed in an area already impacted by the existing reservoir, on land that was badly affected by the 2003 fires and previous forestry plantations.
Protection of the environment is integral to the project.
The dam design includes measures to protect fish populations, particularly to allow upstream migration of the endangered Macquarie Perch.
Climate change and variability have had severe impacts on the ACT region’s water supply in recent years, making these factors key considerations in ACTEW’s planning for our future water supply.
ACTEW has also developed a Greenhouse Gas Abatement strategy for its water security projects. Reducing greenhouse gas emissions is one of our priorities and emissions will be avoided and reduced in the first instance, with offsets being pursued if they are needed.
Will I still be able to visit the Cotter?
Visitors and the local community are encouraged to enjoy Casuarina Sands which was reopened on 9 January 2010, after ACTEW upgraded facilities including parking and additional shade, BBQs and picnic tables.
Watch footage from the Casuarina Sands re-opening event in January 2010 - 26MB
The community will have the opportunity to watch the Enlarged Cotter Dam progress with the opening of a viewing trail and platform in spring 2010.
Due to its proximity to the construction site, Cotter Avenue is closed for approximately two years until completion of the new dam.
How long will the project take?
Construction of the Enlarged Cotter Dam is expected to be complete in late 2011.
How can I stay informed?
Join the Friends of the Cotter community group to be kept informed about projects taking place at the Cotter and to share your memories of the Cotter Precinct with others. You can sign up at www.actew.com.au
Further project information is also available through the Water Security Information Line contact details below.