Blanco Drain Natural Treatment System
Client
Private Client
Project Categories
Tags
valveNature-Based Water TreatmentHydology/HydraulicsRestoring Water Quality in the Salinas Valley
The Salinas Valley is a vital agricultural hub, producing 70% of the nation’s lettuce and other crops. However, intensive farming has led to high nitrogen runoff, which flows into local waterways through the Blanco Drain and contributes to a growing “dead zone” in Monterey Bay. To combat this, FlowWest partnered with the Resource Conservation District of Monterey County to develop a nature-based solution that reduces agricultural pollution while supporting sustainable farming practices.
Innovative Bioreactor Technology
A major contributor to nitrogen pollution is the Blanco Drain, an agricultural drainage channel that collects runoff from lower valley farms. To address this, FlowWest designed and implemented a microbial denitrifying bioreactor adjacent to the drain. This system serves as a scalable solution that individual farms can adopt to treat nitrogen at its source, reducing the overall pollutant load before it reaches sensitive waterways.
Proven Performance and Scalability
Constructed in 2022, the bioreactor features a groundbreaking vertical flow design, eliminating common inefficiencies such as short-circuiting seen in other systems. Initial performance results exceeded expectations, with the system achieving a 99% nitrate removal efficiency—reducing inflow concentrations from 49 mg/L to just 0.5 mg/L during the summer of 2022. This success demonstrates the potential for broader application across the Salinas Valley, providing a sustainable, cost-effective approach to improving water quality and protecting Monterey Bay’s ecosystem.
