Over a 10-year period, B&N has led multiple projects at the Hap Cremean Water Plant (HCWP) that were implemented to improve the water treatment system and increase capacity. Services have included master planning, facilities inspection, studies for regulatory compliance and a capacity increase, and design of repair and improvements.
Hap Cremean was built in 1954 and is the largest water treatment facility serving metropolitan Columbus, Ohio. B&N led a multi-firm team to identify a cost-effective treatment technology for the surface water treatment plant that would:
- Reduce disinfection byproducts in the potable water supply
- Increase the plant’s treatment capacity from 100 MGD to 125 MGD
- Comply with current and anticipated regulatory requirements
Testing to Evaluate Alternatives
The team of B&N and Montgomery Watson Harza worked with the City to conduct pilot- and bench-scale tests that evaluated treatment alternatives which would reduce disinfection byproducts in the potable water supply and ensure compliance with the U.S. Environmental Protection Agency (EPA) Disinfectants and Disinfection Byproducts (DDBP) Rules.
At the conclusion of the study, intermediate ozonation with biologically active filtration (BAF) was chosen as the preferred treatment method to be implemented because it reduces DDBP precursors, and provides the necessary level of treatment with the lowest capital investment and operating costs. The combination of ozonation and BAF is expected to reduce DDBPs in the distribution system by approximately 25 percent.
Improved Water Treatment and Increased Capacity
After successfully completing the two-year treatment evaluations and the pilot- and bench-scale tests, the B&N team was selected to design the BAF and ozonation improvements at HCWP.
During the plant’s evaluation the team also conducted a high rate demonstration study which increased the Ohio EPA approved capacity of the plant by 25%, from 100 MGD to 125 MGD. A portion of the full-scale plant operated at the higher proposed rate to demonstrate the plant functioned properly and produced finished water quality at this higher rate. The increase in capacity was approved by the Ohio EPA and did not require any additional capital improvements.
Energy Savings – LEED® Silver Certification
The ozone production building at HCWP includes the plant’s most energy-intensive process. The project team identified and designed energy savings for the building’s lighting and mechanical systems that resulted in LEED® Silver certification. Sustainable features include:
- Energy efficient heating and air ventilation
- Incorporation of natural light into the building
- Low flow plumbing fixtures for water efficiency
- Locally sourced construction materials
- Recycling of construction debris
Additional sustainable items were selected and implemented in non-LEED portions of the project including the most energy efficient ozonation system and a recarbonation system that reduces carbon dioxide emissions.