Prop 1 Grant Funds Stormwater Reuse as part of the Pure Water Monterey Project

By Mike McCullough, Monterey Regional Water Pollution Control Agency

The Monterey Regional Water Pollution Control Agency (MRWPCA) and the City of Salinas were awarded a $10 Million Grant from the Water Quality, and Infrastructure Improvement Act of 2014 (Proposition 1) to assist with stormwater management projects. The grant money will be put towards the design and construction of stormwater capture projects in and around the City of Salinas. All of the project components will benefit the Pure Water Monterey program, an innovative replacement water supply project with three primary goals; to provide a sustainable source of water supply through advanced water purification and groundwater injection, provide additional recycled water for agricultural irrigation and mitigate seawater intrusion.

Finding beneficial uses for stormwater is a key component of water sustainability on the Central Coast. The projects funded through the grant include diversion structures for the collection of dry weather runoff flows from the Southwest portion of the City of Salinas into the Agency’s regional wastewater pump station. Wet weather storm Stormwater and urban runoff will be captured for purification and reuse.water flows will be directed to an off-site storage location by way of existing infrastructure. The recovery of the off-site stormwater will utilize a refurbished pipeline to return stormwater to the regional wastewater pump station for treatment at the Regional Treatment Plant, providing a large cost savings.

Aside from traditional wastewater treatment, the Pure Water Monterey project will use multiple sources of water, including stormwater, for advanced treatment to be injected into the overdrafted Seaside Groundwater basin. These additional water sources will also increase the amount of water available for use by growers partaking in the Castroville Seawater Intrusion Project in the Salinas Valley.

The diagram below highlights some of the proposed infrastructure improvements in and around the Agency’s regional wastewater pump station outside of Salinas. Construction activities are expected to occur later in 2017.