Parker Water and Sanitation District leaders have long known that groundwater is a diminishing resource within the utility's rapidly developing service area. Their plan for keeping up with growth includes a recently commissioned 10 mgd treatment plant (expandable to 40 mgd) that draws from surface water, groundwater, alluvial well water, and reclaimed wastewater.
Designed by Dewberry, the Rueter-Hess Water Purification Facility in Parker, Colo., is the first plant in the world to incorporate three cutting-edge technologies to meet EPA drinking water standards:
- A coagulation, flocculation, and sedimentation chamber uses microsand to enhance particle sedimentation while reducing the chamber’s surface area requirements.
- A recirculating powdered activated carbon (PAC) chamber cuts costs by sending used PAC back through the system, increasing the amount of contact time between PAC particles and dissolved organic compounds for more aggressive and efficient treatment.
- The treated water is then pumped through ceramic membrane filters to remove remaining particles larger than 0.1 microns in size and any remaining microsand or PAC.
In the first such application in a drinking water system in the U.S., the 600 ceramic membrane modules were specifically chosen for their ability to withstand the sand and PAC particles used in upstream processes and then be cleaned back to like-new condition. The filtration system is anticipated to last much longer than conventional polymeric membranes.
“Sand and powdered activated carbon are very abrasive,” says Dewberry Project Manager/Design Alan Pratt, PE. “Whereas polymeric membranes typically deteriorate over a life of six to 10 years and must be replaced, ceramic members are very durable and can be cleaned back to a new condition.”
The new facility features a 50 cfs pump station that brings surface water from nearby Cherry Creek and Cherry Creek alluvial wells into the 75,000-acre-foot Rueter-Hess Reservoir completed in 2012. Water stored in the reservoir flows by gravity into the plant. After moving through the two ballasted sedimentation chambers and the ceramic membrane filters, the disinfected water is pumped into the district's distribution piping network for use by customers. Wastewater is returned to nearby reclamation facilities and then to Cherry Creek for reuse.
In addition to Dewberry, the project team included Western Summit Constructors Inc. as the primary contractor, Garney-Weaver for construction management, and Kruger Inc. for the ballasted sedimentation and ceramic membrane filter technologies.
“The ability to turn many different water qualities into a high-quality potable supply was made possible only with the combined effort of many companies,” says District Manager Ron Redd.