McCarthy Completes Tomahawk Creek Wastewater Treatment Facility: CEG


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McCarthy Building Companies has completed construction of the Tomahawk Creek Wastewater Treatment Facility in Leawood, Kansas, one of the world’s largest aqua-aerobic disc filtration system facilities for dual-purpose filtration. Started in 2018, the project was completed on time and within budget. The inauguration took place on May 4, 2022.

Located in Johnson County, Kansas, the $270 million expansion is approximately 30% larger than its previous footprint and represents a complete overhaul of the existing facility, which began operations in 1955 with numerous extensions and upgrades over the years.

“Making this type of investment in Johnson County’s infrastructure is critical,” said Johnson County Board of Commissioners Chairman Ed Eilert. “Thanks to 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 supported by a facility that will meet future water quality regulations and control costs.”

The current expansion includes over 30 new structures; more than 130 pumps installed; three tower cranes; 50,000 cu. yards. of concrete ; more than 9 miles. underground utilities; and 792 wells drilled in deep foundations.

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 elected to use the Construction Manager at Risk (CMAR) collaborative delivery method with McCarthy as the construction manager. Additionally, McCarthy’s wholly-owned subsidiary, Castle Contracting, provided concrete services, making the concrete for the project entirely self-executed.

“Building water infrastructure projects like the Tomahawk Creek WWTF is not only an economic driver for the local communities where we live and work, but it also provides sustainable resources that will greatly benefit future generations,” said BJ Peterson, Vice President of Operations, McCarthy Building Companies. in Kansas City.

The Tomahawk Creek WWTP serves approximately 150,000 residents and is one of five wastewater treatment facilities serving approximately half a million area residents. 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 handle wet and dry weather flows of 19 million gallons. . per day (MGD) at 172 MGD.

During much of construction, throughput received at the facility had been diverted to Kansas City, Missouri, for processing. Following the commissioning phase conducted from September 2021 to March 2022, all flows have been processed through the factory.

About McCarthy

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

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

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About Black & Veatch

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

Since 1915, it has helped its customers by addressing the resiliency and reliability of critical infrastructure assets.

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About HDR

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

HDR offers its clients comprehensive professional engineering services in the areas of water, wastewater, stormwater, transportation, energy and construction administration. Its five offices across Missouri and Kansas are staffed by more than 210 multidisciplinary professionals, who work daily with other recognized HDR experts across the country.

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Tomahawk Creek Wastewater Treatment Facility

Location, Timeline

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

Project Highlights

  • One of the world’s largest Aqua-Aerobic disc filtration system installations for dual-purpose filtration
  • During construction, stream received at the facility was diverted for processing to Kansas City, Mo.
  • The site includes more than 30 new structures
  • More than 130 pumps installed on site
  • Three tower cranes
  • 50,000 cu. yards. of concrete
  • More than 9 km. underground networks
  • Eight disc filter tanks with 24 discs per tank

Construction details

  • Demolition and dismantling of existing facilities
  • Establish temporary arrangements for stream diversion.
  • Site works include grading and drainage, underground piping, site roads and construction of a bridge on site.
  • Provide an earth channel to mitigate the impacts of flooding on the site and upstream communities.
  • Modifications to Lee Boulevard to facilitate access to the site.
  • Junction and influent flow control structures
  • Influent pumping station and peak flow
  • Headboard building
  • Primary clarifiers
  • Biological Nutrient Removal Ponds
  • Final clarifiers, associated pumping stations and separation structures
  • Tertiary pumping station
  • Filtration complex
  • Chemical disinfection
  • Effluent re-aeration structure
  • Gravity Thickeners
  • Solids processing building which includes thickening and dewatering
  • Solids digestion and gas storage
  • Waste gas flares
  • Administration/maintenance building

Advanced construction technologies

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

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