McCarthy Completes Construction for Tomahawk Creek Wastewater Treatment Facility

One of the World’s Largest Aqua-Aerobic Disk Filtration System

Installations for Dual-Use Filtration

McCarthy has completed construction at Tomahawk Creek Wastewater Treatment Facility in Leawood, Kansas, one of the world’s largest Aqua-Aerobic disk filtration system installations for dual-use filtration. Begun in 2018, the project was completed on schedule and on budget. The ribbon cutting was held May 4, 2022.

Located in Johnson County, Kansas (suburban Kansas City), the $270 million expansion is facility which began operation in 1955 with numerous expansions and upgrades over the years.

“Making this type of investment in the infrastructure of Johnson County is crucial,” said Ed Eilert, chairman of the Johnson County Board of County Commissioners. “Through this investment and the expertise of everyone who worked on the project, Johnson County Wastewater residents served by Tomahawk Creek don’t have to think about wastewater treatment, they can rest assured that this important service is being taken care of by a facility that will meet future water quality regulations and control costs.”

The current expansion includes more than 30 new structures, more than 130 installed pumps, three-tower cranes, 50,000 cubic yards of concrete, more than nine miles of underground utilities, and 792 deep foundation drilled shafts.

The Tomahawk Creek WWTF was a joint project of Johnson County Wastewater, McCarthy Building Companies-Kansas City, Black & Veatch and HDR. Due to the complexity and tight schedule, Johnson County chose to use the collaborative delivery method of Construction Manager at Risk (CMAR) with McCarthy serving as the construction manager. In addition, McCarthy’s sister company, Castle Contracting, installed the extensive underground piping package further supporting the level of integration, self-perform quality and schedule control required for the project.

“Building water infrastructure projects like the Tomahawk Creek WWTF are not only economic drivers for local communities where we live and work, but they also provide sustainable resources that will greatly benefit future generations,” said BJ Peterson, vice president, Operations, McCarthy Building Companies in Kansas City.

The Tomahawk Creek WWTF serves about 150,000 residents and is one of five wastewater treatment facilities serving approximately one-half million residents in the region. In addition to improving water quality while providing cost-effective long-term treatment solutions for Johnson County customers, the new facility has the capacity to treat wet and dry weather flows from 19 million gallons per day (MGD) to 172 MGD.

During much of the construction, flow received at facility had been diverted to Kansas City, Mo. for treatment.  Following the commissioning phase conducted from September 2021 through March 2022, all flows have been treated through the plant.

About McCarthy

McCarthy is the oldest privately held national construction company in the country – with nearly 160 years spent collaborating with partners to solve complex building challenges on behalf of its clients. With an unrelenting focus on safety and a comprehensive quality program that span all phases of every project, McCarthy utilizes industry-leading design phase and construction techniques combined with value-add technology to maximize outcomes. Repeatedly honored as a Best Place to Work and Healthiest Employer, McCarthy is ranked the 13th largest domestic builder (Engineering News-Record, May 2021). With approximately 6,000 salaried employees and craft professionals, the firm has offices in St. Louis; Atlanta; Collinsville, Ill.; Kansas City, Kan.; Omaha, Neb.; Phoenix; Las Vegas; Denver; Austin, Dallas, and Houston; and San Diego, Newport Beach, Los Angeles, San Francisco, San Jose and Sacramento, Calif. McCarthy is 100 percent employee owned. More information about the company is available online at www.mccarthy.com or by following the company on Facebook, Twitter, LinkedIn and Instagram.