The Monte Vista nitrate treatment plant groundwater project has entered operation, enabling the return of a previously inactive water source to potable supply in Montclair, California.
Developed by Monte Vista Water District in collaboration with Envirogen, the facility uses ion exchange technology to remove nitrate contamination from groundwater at Well 34.
Groundwater source restored after contamination
Well 34 was originally constructed in 2011 but was taken offline in 2018 after nitrate levels exceeded regulatory limits for drinking water. Measured concentrations reached 14 mg/L of nitrate-nitrogen, above the maximum contaminant level of 10 mg/L.
The new Monte Vista nitrate treatment plant groundwater system enables the well to be safely returned to service, providing an additional local supply source for the district.
This is particularly important in Southern California, where water systems face ongoing pressure from drought and reduced availability of imported water supplies.
Ion exchange system enables continuous treatment
The treatment facility consists of two containerised regenerable ion exchange systems designed to operate continuously. Together, the systems treat approximately 2,000 gallons per minute of groundwater.
The process reduces nitrate concentrations to levels below regulatory thresholds, producing treated water suitable for potable use. Pre-filtration removes suspended solids, while an automated regeneration system ensures consistent performance and optimised chemical use.
The containerised design allows for efficient installation and protection of equipment, supporting reliable long-term operation.
What the Monte Vista nitrate treatment plant groundwater project means for water treatment
The Monte Vista nitrate treatment plant groundwater project highlights the growing importance of advanced treatment technologies in restoring impaired water sources.
Nitrate contamination is a common issue in groundwater, often linked to agricultural runoff and historical industrial activity. Ion exchange systems are increasingly used to address this challenge, offering a reliable method for removing dissolved contaminants.
Reactivating existing groundwater sources can be a cost-effective alternative to developing new supply infrastructure, particularly in water-stressed regions.
Projects such as this also support supply diversification, reducing reliance on external water imports and improving overall system resilience.
For more on groundwater and treatment technologies, visit our Groundwater coverage.
Supporting long-term water resilience in California
The reactivation of Well 34 forms part of a broader strategy to strengthen local water resources and improve supply reliability.
By expanding the use of treated groundwater, utilities can better manage variability in imported water allocations and respond to changing climate conditions.
Collaboration between utilities and technology providers is also a key factor in delivering these projects efficiently, particularly where permitting and commissioning timelines are constrained.
Further developments in water treatment and supply infrastructure can be explored in our Water Treatment section.
