The City of Austin has authorized an additional $600 million for the construction contract with MWH Constructors Inc. for the Walnut Creek Wastewater Treatment Plant Expansion to 100 million gallons per day. This amendment, approved on March 12, brings the total contract value to $1.5 billion, building on the original $900 million agreement established in 2024.1
Project Scope and Benefits
The expansion and modernization initiative involves upgrading existing facilities for biological nutrient removal processes, constructing new facilities for a 25 million gallons per day increase, and implementing peak wet weather flow capabilities. Managed under a construction manager-at-risk delivery method, the project includes multiple guaranteed maximum price packages such as flood wall construction, mobilization site services, and effluent pipeline tunneling. This development represents great news for MWH Constructors, a specialized firm in water and wastewater treatment infrastructure, enhancing their portfolio and supporting regional growth. Their website is available at mwhconstructors.com, with details on trade partners at mwhconstructors.com/about/trade-partners and careers opportunities at mwhconstructors.com/careers.
Complementing this, Travis County approved borrowing $138.88 million on March 9 for various infrastructure projects, including $61.09 million for road construction and drainage.2 Separately, a building permit was filed on March 4 for the Texas Facilities Commission Pflugerville State Office Building, signaling further public sector construction activity.3
Near-Term Outlook
As construction progresses through 2032, upcoming milestones include bidding for the 25 MGD expansion package and pursuit of up to $1 billion in federal low-interest loans via the WIFIA program. These steps will ensure operational continuity and regulatory compliance, bolstering local infrastructure resilience.