Canberra Airport is an international leader in water use and has lead a dedicated campaign to reduce water use across the Airport and to educate other water users across the ACT and Australia in how to better use precious water resources.
Our aim is to progressively reduce water use to an absolute minimum via a multi-targeted approach across the Airport. Already we have far exceeded the highest of hurdles, and far exceed any current water standards or requirements.
How we conserve water...
In another “first” for Canberra Airport, our Blackwater Recycling Treatment Plant was launched in May 2007. This system takes sewer (or “black”) water from the buildings and treats it to a drinkable level using a self cleaning membrane system and UV safety filters. After the treatment, the water is then used (along with rainwater captured off roofs) in toilets and externally for irrigation (whilst the water is drinkable, it is not used for drinking or showering). This was the first commercial large scale water recycling system in the ACT, and the first at an Australian Airport.
Notwithstanding that cooling towers are very energy efficient compared to alternative cooling methods, they do however, use a significant amount of water. Much of this loss is because most cooling towers cycle their water two or three times, and then they reject that water into the sewer, accounting for between 10-25% of a conventional building’s total water use. Canberra Airport uses significantly more efficient cooling towers, which cycle the water between 12 to 15 times before rejecting the water into the sewer, using one fifth to one sixth of a conventional tower.
Canberra Airport has taken the initiative to install water efficient devices in all new buildings. These devices include 5A reduced flow shower heads, mixer or infrared taps, 3/4.5 dual flush toilets and waterless urinals. These water fittings use significantly less water than the fittings put into most domestic homes.
The biggest users of water inside most buildings are the urinals; with a typical modern trough system with automatic sensors using approximately 100,000 litres per year (older trough systems use significantly more). Canberra Airport uses a number of different technologies in order to reduce this water consumption to essentially zero. In our newer buildings (and another “first” in the ACT), Canberra Airport utilises waterless urinals. In our existing buildings, an alternative water saving device (the Desert Cube Waterless Urinal System) is used, cutting water usage by about 84%.
Water leakages are a very large source of water use, and typically account for 25% of water consumption in non-monitored buildings. Canberra Airport actively manages and monitors its water use, continuously searching for leakages or potential leakages in its buildings. Water sub meters have been connected to all major uses, and our newer buildings are electronically connected to a Building Management System, which provides alarms when leaks are detected. The Airport employs a licensed plumber on site to repair any leaks and inefficient infrastructure. Three full time irrigation plumbing experts also work on site to repair irrigation leaks and monitor water usage.
Canberra Airport has water tank capacity of approximately 1.38 million litres – the largest non-ACTEW water storage in the ACT. Rain runoff from the Special Purpose Aircraft hangar complex alone is retained in a million-litre tank for irrigation and fire fighting. Water is captured from hangar and office building roofs and stored for use in toilets, irrigation and fire fighting purposes.
In recognition of its role as a major land user in the Majura Valley, Canberra Airport vigilantly manages its stormwater flows and quality to ensure a minimal impact on the Molonglo River and thus Lake Burley Griffin and the Murrumbidgee River.
Stormwater monitoring is an important component of the Airport’s Environment Strategy, and water quality has been monitored at a range of locations around the Airport since 1998.
Canberra Airport’s Stormwater Management Strategy, originally developed in June 2005, considers both the quality and quantity of water, including stormwater detention and reuse opportunities. It is a “living” document and is revised as required.
Canberra Airport also participates in the Sustainable Water Action Management Plan (SWAMP) which is part of the catchment management initiatives for the Upper Murrumbidgee. Canberra Airport was also involved in the preparation of the Molonglo Catchment Strategy 2004 – 2024.
No ACTEW water is used in our external environment at Canberra Airport. Instead, all external water draws from the water recycling, rainwater tanks and ground water. When recycled and rainwater resources are depleted or unavailable, Canberra Airport uses non-potable ground water for uses which don’t involve drinking or showering, further reducing our reliance upon potable ACTEW water supplies. Sub-surface irrigation has been introduced outside some of our newer building, eliminating evaporation in the watering process. Sub-surface irrigation is estimated to reduce water use in irrigation by approximately 30-40%.
Further, grassed stormwater swales and detention basins are used to reduce urban runoff and provide a natural filtration and groundwater recharge system. Innovative stormwater detention basins such as car parks, sporting fields and ponds are incorporated during the design stage of new buildings and infrastructure. Grassed swales and reeds are used to slow down stormwater flow which controls erosion and reduce sediments entering the natural waterways. Slowing down the stormwater flow also reduces flooding and increases moisture in the soil which reduces the need for irrigation.
The planting has been designed to provide maximum amenity in the form of controlled sun and shade whilst also minimising water use. Both larger and smaller plant species are selected for both appearance and drought resistance to reduce water requirements.
A number of additional water conservation measures are used to decrease the use of water in the external environment. Garden beds are re-mulched on a regular basis and wetting agents are used to aid with water penetration and to minimize water loss. Water storage crystals are used in garden beds to utilize rain water and runoff therefore reducing the need for watering. Garden beds are weeded regularly to reduce competition with landscape plants for water. Lawns are regularly aerated to improve water absorption. Rubber stabilizers are used on high traffic lawns to reduce lawn re-establishment.
In smaller areas, artificial grass is used in place of real grass. Artificial grass does not require watering, staying green all-year long, plus it obviously doesn’t require mowing thereby saving on labour costs.
A number of our tenants have introduced their own water conservation initiatives. These include:
Unlike most sweeper trucks, which use water to clean roads and hard surfaces, Canberra Airport’s roads, taxiway and runways are swept with our waterless vacuum sweeper.