The City of Scottsdale's Chaparral Water Treatment Plant recently began operation
treating Salt River Project water using an innovative integrated process consisting of
coagulation for arsenic removal, direct filtration through submerged ultrafiltration
membranes, and granular activated carbon (GAC) contactors for removal of total organic carbon (TOC) and taste and odor causing
compounds. Ancillary processes include plate settlers for wash water recovery and
centrifuges for solids removal. The unique process for this new 30 mgd facility was
developed through six months of pilot-scale operations which competitively evaluated
four membrane systems as well as ozone and two different types of GAC. Membrane
processes were preferred due to the very small site and the highly variable water quality
delivered to the plant. The entire facility, including the 5.5 MG buried reservoir, sits on
only 11 acres and is constructed to minimize neighborhood impact.
Substantial challenges existed for the design and construction of the facilities. In addition
to a very small, irregularly shaped site, the issues of adjacent neighbors needed to be
addressed, views of Camelback Mountain needed to be maintained, the park facilities
needed to be upgraded, significant variations in turbidity and arsenic needed to be
controlled, and disinfection byproduct (DBP) formation needed to be reduced in the system. Clearly, an advanced
treatment system to treat multiple challenges was required.
| Edition : | Vol. - No. |
| Number of Pages : | 5 |
| Published : | 06/01/2007 |
