GBA's Innovations for W7 and CRWD6 Integration

Project Overview

After Water District No. 7 of Johnson County, KS (W7) acquired Consolidated Water District No. 6 of Johnson County, KS (CRWD6), GBA’s Water Environment Group was hired to work with W7 to assess current supply contracts, existing infrastructure and future water demands. This assessment resulted in the recommendation of water supply, pumping and storage improvements.

Project Scope & Innovations

GBA designed and is currently providing construction phase services for a new water supply interconnection with neighboring WaterOne of Johnson County, KS. The improvements include approximately 3,000 LF of 16-inch diameter transmission main, metering structure and connection to a WaterOne 48-inch transmission main and a prefabricated booster pump station.

A future 500,000-gal elevated storage tank to serve the former CRWD6 area is currently under design. GBA assisted W7 with the Kansas Department of Health and Environment (KDHE) State Revolving Loan Fund applications and administration.

The design for the transmission main and booster pump station facility included:

• Hydraulic Modeling and Sizing
• Geotechnical Investigations
• Alternative Alignment and Construction Method Evaluations
• Easement Acquisition
• Coordination with the City of Olathe for construction of the booster pump station building and transmission main within the City’s right-of-way
• Coordination with neighboring home owners associations

The transmission main alignment includes several utility crossings, rock strata, a creek crossing and work within a major 4-lane street.

The booster pump station facility includes three installed pumps with variable frequency drives (VFDs) intended to convey the WaterOne supply and sustain W7 system pressures prior to the construction of the elevated storage tank. The booster pump station is also constructed to accommodate future expansion via the installation of a fourth pump.

Community Collaboration

GBA and partners worked with Johnson County to evaluate the introduction of the new WaterOne wholesale supply and water compatibility as it relates to lead and copper release, and corrosion potential.

The team has coordinated with many members and groups in the area, including WaterOne, City of Olathe, Johnson County and the Olathe School District. Delays from COVID have also been a factor and a challenge during this project, affecting supplies and materials needed.

Project Timeline

GBA services for this project began in April 2019 and construction is expected to be completed in Q2 2023.