Castle Rock Plum Creek Advanced Treatment Water Purification Facility

Castle Rock, Colorado

Best Project Water Environment

OWNER: Town of Castle Rock

LEAD DESIGN FIRM: Burns & McDonnell

GENERAL CONTRACTOR: Garney Construction

Castle Rock has developed a water supply system that can use renewable sources to meet the town’s growing demand. Burns & McDonnell developed a unique drinking water plant that treats both groundwater and surface water sources and helps the town add advanced treatment systems to the plant. The design firm provided piloting, design and onsite construction oversight services, collaborating with the contractor and owner from design through construction and start-up.

The Plum Creek facility now can purify multiple raw water sources to meet drinking water standards, including renewable indirect-reuse water and direct-reuse water. 

water purification plant

Photo courtesy Burns & McDonnell

The project added several features to the operational drinking water plant, including a raw water blending step, biological filtration, advanced oxidation, granular activated carbon, ultraviolet disinfection and residuals handling. The new advanced treatment processes also reduce contaminants of emerging concern such as pharmaceuticals and personal care products, which conventional pretreatment and treatment technologies do not remove, while supporting the removal of giardia, viruses and cryptosporidium beyond regulatory requirements. 

water purification plant

Photo courtesy Town of Castle Rock

Because there is currently no regulatory framework for direct potable reuse treatment in Colorado, the project team collaborated with the Colorado Dept. of Public Health and Environment to invest in an advanced treatment train that is anticipated to go above and beyond requirements for future reuse treatment. 

By pilot testing several of the new advanced treatment processes, staff and operators were introduced to unfamiliar technologies and gained hands-on experience before the improvements were completed. The project has allowed the town to reach a primary benchmark in its renewable-source goals.