White Paper

Performance Of A Conventional Surface Water Plant Using Mixed-Oxidants For Microflocculation And Final Disinfection

Source: MIOX Corporation

By MIOX Corporation

The City of Santa Fe, the capital of New Mexico, is located in the foothills of the Sangre de Cristo mountains in north-central New Mexico. The water utility, Sangre de Cristo Water Division, was purchased by the City from Public Service Company of New Mexico (PNM) in July 1995. The utility is being operated by PNM Water Services through June 2001 when the City will take over full operation. The service area is about 35 square miles and ranges from approximately 8,000 feet to 6,300 feet elevation.

Santa Fe’s potable water supply comes from surface and ground water sources. The surface water source is from snow-melt and summer thunderstorm run-off from the mountains. This water is detained in McClure Reservoir (7876 ft elevation) and Nichols Reservoir (7483 ft elevation) upstream from the CRWTP, a conventional plant built in 1974 with a design capacity of 8 MGD. Because the City has limited surface water rights, and due to decreased demand, the treatment plant usually shuts down for 60 to 90 days during winter. The reservoirs thaw in spring and turn over in autumn, and during the summer rainy season, raw water turbidities may exceed 5 NTU.

The ground water sources come from two well fields, 8 wells located within the City and a well field with an additional 8 wells near Buckman Crossing, 14 miles northwest of the City. Individual well production varies, but the Buckman field can produce as much as 6 MGD. Santa Fe’s water production ranges from approximately 6 MGD in the winter to about 17 MGD in the summer, with a historical high of 22 MGD. During summer peak demand, all production sources must be used. Santa Fe plans to add to its sources in the next 5 years by taking advantage of surface water rights from the San Juan–Chama project. The subject of this paper is the process changes that have occurred at the CRWTP by use of MIOX.