Melbourne Market Authority saving water

Meters detect leaks providing environmental and cost benefits

After setting a target in January 2007 to reduce potable water consumption by 80% on the Melbourne Market Authority (MMA) site, CEO Peter McLennan has led the organisation on a dynamic water-saving quest that has achieved this goal. This in turn ‘flows' to a water cost reduction from around $13,000 per month to less than $3000 per month even after factoring in the 20% increase in Melbourne Water Company water levies in July 2008.

The most important component to these savings, according to Peter McLennan, is being able to monitor usage because, just like money, you can't manage what you can't account for. To achieve this, MMA installed the internet-based Watersave Smart Meter in May 2008. It enables users to monitor water usage data in real time via a log-on and password, with water usage updates from the system every 15 minutes.

The system almost immediately revealed highly abnormal and expensive usage of up to 428,000 litres per day. Two 8000 litres per hour underground leaks were located and repaired and this action immediately cut water usage to around 70,000 litres per day. The two leaks were located in underground 100 mm pipes - one leaking into the stormwater system, the other in a fire sprinkler system under a concrete floor. With additional recent water leaks found using the Watersave technology, MMA has reduced its average potable water usage to around 40,000 litres per day.

The Smart Meters enabled MMA to segregate the market into three separate parts and give feedback within half an hour as to whether actions taken to reduce water were successful. According to Peter McLennan, the accuracy of the Smart Meters enabled the identification of water losses as small as 6 L/min in systematically segregated areas within the site. Once a meter went to zero, they knew there were no leaks in the area. On 23 April 2009, the MMA could safely say for the first time that there were no water leaks or running toilets on the site.

The MMA's water usage reduction measures included the installation of a 150,000-litre tank to capture rainwater from the roof of the flower market, which is used for the daily market floor washdown when available. The installation of waterless urinals and ceasing use of potable water on landscaped areas further reduced water usage. A system of regular communication to market tenants was also implemented through market circulars and the installation of signage to remind people of their responsibilities in relation to water usage.