San Diego County Public Water System Wellhead Iron and Manganese Treatment System

San Diego County, CA


PACE led the design-build team and served as engineer-of-record for a groundwater water treatment facility. The facility, built in two phases, treats 99% of the water annually and removes Iron, Manganese, and Arsenic to meet EPA Primary and Secondary drinking water standards. PACE also provided the programming, installation and startup of a site-wide SCADA system for all production and distribution facilities. The system consists of 12 potable water wells, 6 irrigation wells, 5 potable water storage tanks and the groundwater treatment facility.


A 500 GPM iron and manganese filtration system was designed and installed using a brand-new proprietary filtration media (Penox), allowing the client to completely remove Iron and Manganese from their potable water supply without the use of complicated chemical injection systems. Iron and Manganese had become a problem due to discoloration of the water and sediment build-up within facility boilers. The client was spending an estimated $20,000 a month on cartridge and bag filter systems to remove sediment.


With the new system, simple backwashing completely restores/regenerates the media’s removal capacity. The system does not require costly media replacement typical with conventional systems (i.e. green sand filters). The backwash from the filters is sent to the wastewater reclamation facility at no cost. As intended, Iron and Manganese are no longer discoloring laundry or leaving sediment in the pipes. A second benefit of the filtration came as a surprise. The media also has the ability, in the presence of “free” iron, to remove arsenic. Lab tests revealed the filtered water had up to 50% less arsenic than the influent. With a small footprint sized system in mind, PACE was able to reduce capital and operational costs significantly and still provide a total treatment capacity of 500 gpm. PACE continues to provide testing and operating supervisory oversight services while the client manages the day to day testing.


Key Features:

  • 500 gpm well-head treatment system
  • Treats 99% of the water annually and removes iron, manganese, and arsenic to EPA drinking water standards
  • Completely removes iron and manganese from the potable water supply without chemical injections
  • Multi-barrier treatment system including GAC filtration, Penox filtration, and chlorine disinfection
  • Saved client $20,000/month by using Penox filtration media
  • Simple backwashing completely restores/ regenerates the media’s removal capacity
  • Reduced arsenic contaminant by up to 50% in the water supply expansion from 200 GPM of iron and manganese removal to 700 GPM
  • Start-up and commissioning services
  • Instrumentation and controls integration


Water Treatment