McCarthy Completes Tomahawk Creek Wastewater Plant : CEG


(Image by McCarthy Building Companies)

McCarthy Building Companies has completed construction of the Tomahawk Creek Wastewater Treatment Plant in Leawood, Kansas, one of the world’s largest dual-use filtration aqua aerobic disc systems. The project, which started in 2018, was completed on schedule and on budget. The ribbon cutting took place on May 4, 2022.

Located in Johnson County, Kan., the $270 million expansion is approximately 30 percent larger than its previous footprint and represents a complete overhaul of the existing facility, which opened in 1955 with numerous additions and upgrades over the years was taken.

“This type of investment in Johnson County’s infrastructure is critical,” 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 need not worry about their wastewater treatment, knowing that this important service is being provided by a facility that does so 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 cu. Meter. concrete; more than 9 mi. from underground utilities; and 792 boreholes for deep foundations.

The Tomahawk Creek WWTF was a collaborative effort between Johnson County Wastewater, McCarthy Building Companies-Kansas City, Black & Veatch and HDR. Due to the complexity and tight schedule, Johnson County chose the Construction Manager at Risk (CMAR) collaborative delivery method with McCarthy as the site manager. In addition, Concrete Services provided by Castle Contracting, a wholly owned subsidiary of McCarthy, meant that the project’s concrete was entirely self-concreted.

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

The Tomahawk Creek WWTF serves approximately 150,000 residents and is one of five wastewater treatment plants serving approximately half a million residents in the area. In addition to improving water quality while providing cost-effective, long-term treatment solutions to Johnson County’s customers, the new facility will have 19 million gallons of wet and dry weather effluent treatment capacity. per day (MGD) to 172 MGD.

During much of the construction work, incoming power at the plant was diverted to Kansas City, Missouri for treatment. After the commissioning phase, which ran from September 2021 to March 2022, all streams through the plant were treated.

About McCarthy

McCarthy Building Companies Inc. is the nation’s oldest privately held national construction company – with nearly 160 years of experience working with partners to solve complex building challenges on behalf of its clients. With a focus on safety and a comprehensive quality program that encompasses all phases of each project.

With approximately 6,000 employees and tradesmen, the company has offices in St. Louis; Atlanta; Collinsville, IL; Kansas City, Kansas; Omaha, Neb.; Phoenix; Las Vegas; Denver; Austin, Dallas and Houston; and San Diego, Newport Beach, Los Angeles, San Francisco, San Jose and Sacramento, California. McCarthy is 100 percent employee-owned.

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About Black & Veatch

Black & Veatch is a 100% employee-owned global engineering, procurement, consulting and construction company with a more than 100-year track record of innovation in sustainable infrastructure.

Since 1915, it has been helping customers by taking care of the resilience and reliability of critical infrastructure assets.

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About HDR

HDR began in 1917 as a one-office business with 12 employees designing water and sewerage systems for new cities and towns throughout the Midwest. Today, more than 100 years later, HDR is one of the largest full-service architectural and engineering firms in the United States, with more than 11,000 employees worldwide.

HDR provides customers with comprehensive professional engineering services in the fields of water, sewage, stormwater, transportation, energy and construction management. Its five offices throughout Missouri and Kansas are made up of more than 210 multidisciplinary professionals who work daily with other recognized HDR professionals across the country.

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Tomahawk Creek Sewage Treatment Plant

location, timeline

  • Tomahawk Creek Wastewater Treatment Plant (WWTF), 10701 Lee Blvd., Leawood, KS 66211
  • Construction began in 2018 and was completed in 2022.

Project Highlights

  • One of the world’s largest installed aqua aerobic disc filter systems for dual-use filtration
  • Power arriving at the plant during construction was diverted to Kansas City, Missouri for treatment.
  • The site includes more than 30 new structures
  • More than 130 installed pumps on site
  • Three tower cranes
  • 50,000 cu. Meter. concrete
  • More than 9km. from underground utilities
  • Eight disc filter tanks with 24 discs per tank

construction details

  • Demolition and decommissioning of existing facilities
  • Establishment of temporary river diversion arrangements.
  • The site works include grading and drainage, underground piping, site roads and the construction of a site bridge.
  • Providing an earth channel to mitigate the impact of flooding on the site and upstream communities.
  • Changes to Lee Boulevard to allow access to the site.
  • Confluence and flow control structures
  • Inlet and peak discharge pumping station
  • Headworks building
  • primary clarifier
  • Biological nutrient depletion tanks
  • Secondary clarifier, associated pumping stations and splitter structures
  • Tertiary Pumping Station
  • filtration complex
  • Chemical disinfection
  • Sewage revitalization structure
  • gravity thickener
  • Setup of solids processes, including thickening and dewatering
  • Solids digestion and gas storage
  • exhaust flares
  • administration/maintenance building

Advanced construction technologies

  • Drone pilot on site for real-time coordination photos.
  • Using XS10 scanning technology for accurate layout and as-built.
  • Using Trimble Earthworks for GPS-enabled heavy equipment for precise excavation at the right grade and elevation.
  • 3D modeling technology for the entire facility to facilitate construction coordination, eliminate conflicts and improve quality.

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