Water efficient fixtures, fittings and appliances can be selected in line with the following WELS ratings:
3 star shower - 7.5-9.0L per minute or for very water efficient choose 6-7.5L/min. Note the spray from different shower heads can feel different with the same amount of water. Better shower heads optimise the feel of the spray from the same volume of water. In our testing a number of years ago we found Methevan Satinjet to be the nicest feeling shower head.
4 star toilets - Dual flush 3/4.5L per flush. When the cistern and pan are purchased as a suite these toilets flush better than older toilets that required more water. The design of the pan is critical. Do not match a new design cistern to an old toilet pan or it will not flush properly.
5 or 6 star star bathroom taps - if the person does not want to fill up the basin regularly then specify a lower water volume 6 star tap.
5 or 6 star kitchen taps - if the client has a dishwasher and they rarely wash dishes in the sink, then a 6 star with lower water volume is ideal for washing fruit and vegetables or rinsing plates.
4.0 star (water) dishwasher. Also maximise the energy star rating of the dishwasher. Star ratings for both are presented on dishwashers.
Rainwater and stormwater treatment
With our towns and cities becoming increasingly dense urbanised environments, we are seeing reductions in sizes of back yards, replaced with greater coverage of hardstand roof or paved areas (even artificial grass which is generally non permeable).
In order to live well within our more dense urban environment we need to ensure the increased run-off from developed sites does not flush out or deliver too many additional pollutants into our waterways and kill creek, river and marine life.
Ideally development sites would allow the same amount of infiltration into the ground to the water table, as occurred pre-western development. This is not always easy to do.
Rainwater collection is now often required in new buildings or extensions for the following reasons:
Retention and re-use of water for water saving benefits
Temporary onsite detention while the peak rainwater event occurs. Detention tanks collect rainwater or stormwater and slowly release it into drains after the rainfall event so stormwater drains in the street do not over flow during the peak rainfall time. Detention tanks are now more commonly required due to the increased water going into existing drains potentially built to accommodate our development style of 50+ years ago.
Rainwater collected off roofs and retained on site permanently for re-use allows pollutants from leaf litter debris, animal faeces and particles in the air to settle to the bottom of tanks. The water is often required to be used in toilets which means the water with the pollutants do not go into our stormwater drains and downstream creeks. Instead they go into the sewer system for further cleaning at sewer treatment plants. Toilets are required to be connected to tanks as they are regularly flushed, and the water volume is regularly run down creating more capacity for tanks to perform the detention or retention functions.
Onsite rainwater infiltration where rainwater is cleaned naturally as if passes through soil and down to the water table may be an option in some sites. As mentioned previously, this would be an ideal solution - to replicate pre-development levels. Allowing natural systems to operate in a similar fashion is the ultimate in low impact development!