By Michael Di Matteo
Our visions for smart cities — with lush vegetated buildings, pristine living streams and lakes, and resilience to weather extremes — will be realised only if we plan for our most precious resource: water.
In this article, Michael highlights some emerging smart cities water management approaches. These approaches show how getting the right amount and quality of water, where and when we want it, can achieve multiple smart city objectives. — Adam Beck
Water systems under pressure
Urbanisation and climate changes stress our city water systems by demanding too much of them with too little time to respond. The main drivers are:
- More roads, carparks and buildings producing more runoff in less time.
- More activity generating more pollutants.
- Increased urban temperature extremes resulting in drying-out of cities.
We are already seeing the limitations of our existing urban water management. Examples include:
- Drainage pipes and channels flooding more often.
- Natural stream degradation, loss of biodiversity and loss of natural beauty.
- Stressing urban vegetation.
Thankfully, there are some smart approaches emerging to help manage these impacts.
Thanks, smart tanks
We can now operate urban water infrastructure to make use of its existing potential and achieve multiple objectives. Better weather forecasts and mobile communication make this possible.
For example, we can make water storages 'smart' by equipping them with an outlet structure that releases or holds onto water as needed.
South East Water in Victoria has developed Tank Talk, a technology that allows rainwater tanks, used for harvesting water all-year round, to adapt to storm events. A remote-controlled outlet can be directed to empty a tank in anticipation of a storm to catch rainfall at critical times and reduce flooding in our streets.
In addition, the same device can allow water to be released slowly over time to mimic the natural (pre-urban) flow of water. This will help to restore urban lakes and streams to a more natural and healthy state.
City cooling system?
When Sydney sweltered this year, people sought out the beach to cool down. So, we intuitively know that water is key to our well-being to combat extreme heat in our cities.
In the past, we turned off the tap in summer and let our parks and gardens brown-off to save water. But, as Greg Ingleton at SA Water and Adelaide Airport discovered, when we irrigate near urban areas the watered areas can be up to 3oC cooler. There’s a great TED Talk here.
Irrigating our urban areas in summer could cool our cities. This could reduce urban heat island impacts, and possibly reduce extreme-heat related deaths.
What's better, we can use treated recycled water or harvested stormwater to do this. It's in plentiful and reliable supply, so won't affect water security, and it’s nutrient-rich so it can fertilise urban vegetation. As this water would end up flowing to the sea anyway, using it in our cities keeps nutrients out of our marine environments where they're not as desirable.
Water features in smart cities
A smart city is also a water-smart city. Managing water will be a key feature to achieving multiple liveability benefits in our future smart cities.
This article was written by Michael Di Matteo, an environmental engineer at Water Technology Pty Ltd and a member of the Smart Cities Council Emerging Innovators. The views expressed here are entirely his own.