Saving water at JCC

In 2006, the Queensland Government Accommodation Office (AO) determined that its planned new Government Joint Contact Centre (JCC) should be as “green” as possible. The building was to achieve a high Environmentally Sustainable Design (ESD) rating. Design decisions had to be framed to achieve “green” benefits, short payback periods and highest possible quality.

Specifically, AO said, the project was to achieve at least the Queensland Government's benchmark of 5 Star Green Star Office Design buildings, and adhere to strategic policies relating to the reduced consumption of water and energy as well as use of renewable and sustainable construction materials.

Zillmere JCC. Image courtesy of Green Building Council Australia

At JCC Urban Developer has dramatically proved its worth.

Specific water supply achievements modelled with the help of Urban Developer at JCC include:

  • Within the building grey water recycled from hand basins and showers is re-used for toilet flushing.
  • Some 3.3 cubic metres of stormwater is harvested each day to supply the cooling towers.
  • A further 4.75 cubic metres of stormwater harvest from the eastern car park surface is used to irrigate gardens
  • Overflow from stormwater harvest tanks is directed to bio-filtration beds to reduce runoff peaks
  • Water quality objectives have been met for site runoff from all design storm events up to and including the 20 yr Average Recurrence Interval event. The water quality improvement features include a combination of first-flush diverters, oil/grit separators, vegetated swales, and bio-filtration basins.

As the precinct records supply flows across the building, it will provide good validation of the models ability to reflect real world situations.

Urban Developer joins the well-known music urban stormwater software in the eWater Toolkit.

While music addresses the water quality aspects of urban stormwater management, Urban Developer takes an integrated management approach to stormwater and provides support for the assessment of a broader range of options, including concept design for water quality and quantity objectives. The new Toolkit member can handle the required feedback loops and will ultimately evaluate water quantity and quality considerations in a single framework.

At the same time, the project was also seen as giving Brisbane City Council a useful way to assess the feasibility of using Water Sensitive Urban Design (WSUD) techniques to minimise office water use. The precinct was to form the basis of future Integrated Water Cycle Management planning depending on the outcomes of this design.

The results have achieved all expectations. In late 2009 JCC was awarded a 6 Star Green Star - Office Design v2, putting it amongst the greenest building designs in the world. At the time of certification (25 September 2009), JCC had achieved the highest number of points (92/100) to date for any Office Design v2 project in Australia.

These advances will be cemented with the help of Urban Developer, a new tool to support Integrated Urban Water Management (IUWM) from eWater CRC, which gives JCC the benefit of a sophisticated IUWM modelling software to analyse the effects of water harvesting and re-use on minimising mains water consumption.

Innovative water use includes collection and treatment of five sources of water which are used to flush toilets, (greywater from showers and hand basins, fire test water, condensate from dehumidifiers and stormwater from car park areas). Harvested rainwater from the JCC roof meanwhile supplies sophisticated cooling towers which have their own water treatment system designed to reduce water usage. The sole source of water for the water efficient irrigation system is harvested stormwater from the car park area, which is first treated using WSUD techniques.