Microalgae have been gaining attention as a sustainable, less energy-intensive method for wastewater treatment. This involves growing them in the effluent, where they consume compounds containing nitrogen and phosphorus, as well as heavy metals, pesticides, and particular toxins. Microalgae view these as valuable nutrients, effectively removing pollutants from the water.

A lot must go right for us to have water for people and the environment here in Victoria. It’s got to be the right amount, of the right quality, at the right time and place. It’s something that many of us take for granted. The systems and institutions that get that water to us—the infrastructure, governance, maintenance practices, and demand management—are largely invisible to us.

In the latter part of the last century “cloud-seeding” was the favoured way to make it rain on a local catchment, likely at the expense of rainfall in some distant and unknown place. Historians have noted that, often, one of the first acts of colonial powers has been to modify the hydrologic cycle to their advantage by building channels and dams.

When we think of pollution in streams and rivers, we tend to think first of rubbish in water; the litter traps along the Yarra River in Melbourne’s CBD that are often overflowing, or the empty plastic bottles along the Moonee Ponds Creek. But water pollution takes many forms, from physical trash to invisible chemicals that accumulate in our waterways.

Victoria can simultaneously solve Melbourne’s future sewerage crisis whilst building a sustainable carbon credits sector. A common sight for Melbourne’s residents in the 1850’s would have been carts full of “nightsoil” trundling down Flemington Road. Melbourne subsequently built one of the world’s best municipal water systems, supporting the quality of life its residents enjoy today.