May 18, 2023
May Spotlight: $86,000,000 Capacity Expansion of our South County Regional Wastewater Authority Facility
Hello Gilroy!

This month I’d like to Spotlight the Capacity Expansion Project of our award-winning South County Regional Wastewater Authority (SCRWA) facility. SCRWA Programs Manager Saeid Vaziry will be joining me for the next Conversation and Coffee with the Mayor on Saturday, June 3 at 9:30am in Council Chambers where you will hear firsthand how this expansion will handle wastewater treatment, water recycling, and future growth in our community. Portions of this Spotlight are quite technical as a heads up to non-techies like me, and yet it is fascinating to see the organisms responsible for the biological treatment that is accomplished in only 56 hours. At the very least, be sure to read the last section titled The Treatment Process and include your kids!

The SCRWA facility is amazing, and it’s about to get even more amazing. Please join us and share your enthusiasm for how well SCRWA is run, performs, and plans for the future of Gilroy and Morgan Hill with the Capacity Expansion Project happening now.

See you on June 3rd!

Mayor Marie Blankley, CPA
Overview from the Mayor

The SCRWA is a joint powers authority of the cities of Gilroy and Morgan Hill. Formed in 1992, the Authority serves both cities treating approximately 2.2 billion gallons of wastewater per year and producing 920 million gallons of recycled water per year for use in landscaping, agricultural, industrial, and other applications. It is governed by a five-member board comprised of three (3) Gilroy city councilmembers and two (2) Morgan Hill city councilmembers. The costs to operate the SCRWA facility are shared by the cities of Gilroy and Morgan Hill in a current ratio of 55/45, respectively. Gilroy City Administrator, Jimmy Forbis, serves as the SCRWA General Manager. The facility’s daily operations are provided under a third-party contract with Jacobs, a Denver based company with a long-established exemplary reputation for outstanding environmental stewardship.
The SCRWA has been recognized for its efficiencies and operational acumen and was honored with “Plant of the Year” award in 2022 by the Monterey Bay Section of the California Water Environment Association. In addition, the SCRWA received the Plant Safety Award (1 to 25 employees) from the State of California in 2007 and received the top award in California for the 2018 (1st place) and 2020 (2nd place) “Overall Plant of the Year”. Definitely a facility we can all be proud of!
About SCRWA Programs Manager, Saeid Vaziry

Saeid Vaziry has been a leader of environmental programs both in the public and private sectors throughout central California. For 18 years he has brought his concepts and leadership to the SCRWA and continues his work to pursue environmental protection while optimizing ratepayer dollars. As the recipient of the Engineering Achievement-of-the-Year Award by California Water Environment Association, he has honored the SCRWA commitment to the environment with his pursuit of programs and projects that not only focus on efficient and effective operation but do so without ever losing sight of the need for sustainable and environmentally friendly solutions. Mr. Vaziry is a licensed professional engineer in California, has other work-related certifications and a bachelor’s degree in Civil Engineering from California State University in Fresno. He has worked in local governments at the management level for about 30 years and has an additional 10 years of engineering experience in private consulting.

A Visionary Facility Balancing Technology with Nature

The Gilroy-Morgan Hill SCRWA Facility (Plant) is a wastewater treatment and water reclamation facility that operates as a model of energy efficiency and cost-effectiveness. As the Santa Clara Valley has grown, so has the treatment plant. Today, the facility serves a population of over 105,000 people regionally and is undergoing expansion to meet the future demands associated with growth in our community. The expansion will ensure the health and safety of the Gilroy-Morgan Hill region and preserve its environment and economic vitality.

The Plant is located at the southeast tip of Gilroy. Its capacity in 1994 was to treat 7.5 million gallons of wastewater per day (mgd). Major upgrades have since been made and the facility was re-rated to 8.5 mgd capacity in 2009. And after completion of the expansion project currently underway, it will have the capacity to treat 11 million gallons per day.

To translate these point-in-time capacities into population-weighted average, the Plant currently has the capacity to support about 83,000 people in Gilroy alone. After the expansion, it will support a Gilroy population of 108,000, a 30% increase. In view of the new State housing mandates, the building permit counts were also re-evaluated to determine how potentially higher growth over the next three to five years would affect flow projections. The Plant will continue to provide adequate service to its customers in accordance with both Gilroy and Morgan Hill’s General Plans into 2040.
Record Year for Recycled Water Production

Recycled water is wastewater that has been treated and disinfected to a quality that can be reprocessed under controlled conditions for safe beneficial uses. The SCRWA, in partnership with Valley Water, operates a recycled water facility within the same location. The recycled water facility was expanded in 2006 to a reliable treatment capacity of 9 mgd, and in 2018 was further enhanced with ultraviolet light disinfection system, new pump station and river discharge facilities. The upgrades associated with the Plant expansion will improve water quality and support additional production as cities steadily grow, preserving our long-term potable water supply.

Most of the treated water is recycled in Gilroy and used in areas within Santa Clara County for such uses as agricultural, irrigation of golf courses, city parks, outdoor landscaping, dust control, and some industrial uses. In 2022, the Plant produced 917 million gallons of recycled water. It is a new record for recycled water production at SCRWA, and about 70 million gallons more than the previous record set in 2021.

Investing in Plant Infrastructure

Over the last two decades, the Plant has gone through many changes, and more significant construction is currently underway with the design of a membrane bioreactor to ensure it remains reliable with best available technology. Using cutting-edge membrane technology for nutrient removal also provides higher quality effluent for beneficial reuse.
The $86 million project, cost-shared by Gilroy and Morgan Hill, will feature a new headworks and screenings facility, solids building, bioreactors, membrane basins, blowers, chemical feed and storage facilities.
The construction, which broke ground in 2021, is scheduled to conclude in 2025. When completed and new facilities operational, the Plant will be able to treat more water than ever – from the current 8.5 million gallons daily to 11 million gallons daily, allowing for long-term growth in the cities of Gilroy and Morgan Hill.
Roadmap to a Successful Plant Expansion

SCRWA’s approach to expand the treatment capacity was very timely as significant changes to the current treatment process will go into effect to meet the state and federal regulatory requirements and allow the facility to continue to provide adequate service to its customers and the demands associated with future growth in the area in accordance with both cities’ General Plans.

The expansion project has undergone a comprehensive evaluation, capacity verifications and assessments, along with intensive planning, design, and value engineering efforts. Over the past decade, population and development growth were evaluated along with flow projections for the cities, which determined that capacity expansion is required to accommodate future growth and provide more redundancy and reliability. The evaluations indicated that the current treatment capacity is sufficient until about 2025/2026, at which time new facilities will be needed. The new facilities are on track for completion in 2025 and expected to be in service by 2026.
Financial Impact of Expansion

There is no financing provided through SCRWA. Gilroy and Morgan Hill are separately financing their respective portion of the expansion per the Joint Powers Agreement as follows:
  • Gilroy - 58.1% ($50 million)
  • Morgan Hill - 41.9% ($36 million)

Thanks to the SCRWA Board’s vision to prioritize the expansion and fast-track project development, this project avoided higher deferred construction costs and future regulatory uncertainties that can impact the project timing and cost. The city also benefited from favorable debt issuance timing and realized a historically low rate.

In 2020, SCRWA took advantage of a competitive window to advertise the project and bid construction and managed to avoid the detriments of price escalation in key commodities that Water and Wastewater business depends on. These include factors such as inflation, equipment shortage and material delays that have since impacted other projects in the Bay Area and throughout California due to construction market saturation by the numerous capital improvements that were planned or underway at wastewater treatment facilities.

The Treatment Process

Treating wastewater is a green process which produces beneficial byproducts, and prevents pollutants from reaching our groundwater, lakes, and rivers. Wastewater comes to the Plant in one of two ways:
  • Pipelines throughout Gilroy and Morgan Hill collect waste from households, industry, and retailers.
  • Waste from septic tanks throughout South County is trucked to the facility.

Both systems bring waste to the primary influent pump station where it passes through vertical steel bars screens where large objects such as sticks, rocks, paper and rags are removed; next flow moves to headworks of the plant and heads to biological treatment. During biological treatment, wastewater is exposed to bacteria in aeration basins. The bacteria decompose organic material and ammonia and produces harmless nitrogen gas and biosolids byproduct. At times unexpected things make it to the bar screens (e.g., toys, coins).

All the processes at the Plant are monitored and controlled using a state-of-the-art computer network. At control terminals located throughout the facility, operators can make instantaneous adjustments as needed. Throughout the process, samples are collected and tested at an on-site state certified laboratory to ensure that the water meets health standards and strict levels of discharge for pollutants set by state and federal agencies.

As waste is a vital natural resource for our communities, the treated wastewater is recycled around the community and the stabilized bio-solid is mixed with green waste and composted for beneficial reuse. Many of the treatment processes at the Plant mimic how nature repurifies water yet accelerated. It only takes 56 hours from the time untreated wastewater reaches the facility to the time it is treated and safely discharged. The organisms in the biological treatment are fascinating! Water Bears prey on other microbes and are a sign of healthy secondary treatment. Spirochetes eat anything, including hazardous materials.

To conclude, below are some pictures of the fascinating and hard-working organisms that can be found at the Plant.
Water Bear (Tardigrade)
Stalked Ciliates (Cluster)