Hunter Valley, Australia

"Removing Nutrients from Treated Wastewater"

How should Australia's premier wine growing region remove nutrients from treated wastewater in an environmentally friendly manner?

MWH faced this task in Hunter Valley. For this lush valley, MWH created a new US $10 million wastewater treatment plant that uses an innovative process to protect rivers, lakes and streams.

The fertile Hunter Valley required such an approach.

This region has long played a key role in the economic development of New South Wales — Australia's most populous state. The navigable Hunter River helped establish the region as a major trade route for goods traveling within the country — and those destined for its largest seaport, nearby Sydney.

Each year, thousands of visitors from around the world descend on the green valley.

Today, more than 80 of Australia's most prestigious winemakers are located along the valley river's winding path. By applying a new wastewater treatment strategy, local officials are working to protect these rich natural resources for generations to come.

Chemical-Free Process

MWH teamed with Australia's largest infrastructure developers under a design-build contract to create the wastewater treatment plant. The facility uses a chemical-free process that removes nutrients from treated water before it is discharged into the Hunter River.

This process is known as biological nutrient removal (BNR). It ensures that compounds, such as phosphorous, are largely removed from treated effluent. That way they won't create environmental havoc when discharged into rivers and lakes.

Looking ahead to future demands, the team considered both capacity expansion and technological change. As a result, the new facility can accommodate technological tune-ups that may improve nutrient removal performance. It also allows greater flexibility to meet changing loads and future regulatory requirements.

The Hunter Valley operation has a current capacity of approximately four million gallons daily. This should satisfy regional population growth for the next 15 years.