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Wastewater – every community generates it, and though it may not be a popular topic of casual conversation, wastewater management is a critical service for community health and an exciting frontier for advancements in sustainability and waste reduction.

Water treatment construction frequently involves several public and private stakeholders and can benefit greatly from a collaborative contracting method such as progressive design-build. Relations with nearby communities and those communities’ rapidly changing needs may require design evolutions during construction. Under a progressive design-build model, all parties – owners, designers and contractors alike – are empowered to fully understand these changes and effectively collaborate through them.

Introducing Sterling Natural Resource Center

�۽�ֱ�� is delivering the Sterling Natural Resource Center (SNRC) water recycling facility in San Bernadino, California, for the East Valley Water District (EVWD). The facility plays a vital role in the region’s water infrastructure and sustainability efforts, processing eight to ten million gallons of water per day (mgd) and mitigating drought conditions by replenishing the Bunker Hill underground aquifer.

“EVWD entrusted our team to expedite construction for the new water recycling facility,” says Operations Manager Tom Murray. “Leveraging a progressive design-build contracting method enabled us to meet that demand on an accelerated schedule, with major construction activities beginning before final designs were even complete.”

As contractors, we might typically provide a guaranteed maximum price (GMP) with roughly 60-70 percent of drawings complete. On SNRC, we provided the district with a GMP based on less than 30 percent of completed designs. Shortly thereafter, we mobilized our excavation teams and began construction just months after submitting our proposal.

By contributing our design and construction expertise as the project progressed, we helped EVWD meet not only an accelerated project timeline but also their budgetary goals. As a California Special District, EVWD is federally funded by user rates, state bonds and grants and thus serves as a steward of the public’s resources. Both speed-to-market and budget reliability were important goals for our team to meet.

Work in the Public Eye

Wastewater treatment facilities, whether for public utility districts or private companies, often involve intricate layers of communication, management and resolution with many invested stakeholders including city councils, state authorities and regulatory agencies. On SNRC, each stakeholder had the opportunity to review and comment on the design.

“�۽�ֱ��’s and EVWD’s progressive design-build solutions for SNRC ensured that the team could quickly adapt to and integrate design changes,” Tom adds. “At the same time, we successfully helped our client meet their budgetary goals and create an industry-leading facility for a sustainable future.”

When two of our stakeholders, the San Bernadino Valley Municipal Water District (SBVMWD) and the City of Redlands, were unable to reach an agreement on the planned discharge location, the team collaborated on a solution. SBVMWD purchased a new parcel of land for the discharge location, and SNRC developed the new routing and design to meet this change.

Because the new discharge location, Weaver Basin, was located farther away from the facility, a change order and budget revision were necessary. Again, our progressive design-build approach ensured that our team and all stakeholders could more effectively collaborate to identify schedule impacts and perform cost analysis for the new scope.

Progressive Design-Build Meets Progressive Environmental Goals

As construction of the Sterling Natural Resource Center progressed, �۽�ֱ�� and the East Valley Water District identified several new opportunities to enhance the facility’s waste reduction capabilities, adding to its long-term community value and environmental sustainability efforts.

Though the initial design did not incorporate solid waste handling in the treatment process, EVWD made the decision to incorporate solid waste handling into the facility. SNRC takes in wastewater from the surrounding community, processes out solid waste and filters the water through membrane bioreactors, then disinfects the water with ultraviolet light before it’s conveyed to the Weaver Basin. The filtered solid waste must go somewhere, and the original project scope involved the capability to dewater and transport the solids to a nearby landfill.

Our team quickly adapted to the necessary modifications and, in collaboration with equipment vendor Anaergia, designed the added solids processing infrastructure. The end result is an enhanced improvement to the facility’s sustainability. Rather than transporting solid waste to a landfill, that waste is digested into biogas then utilized to fuel a pair of combined heat and power generators that create enough energy to power the entire facility and channel any surplus back onto the electrical grid.

Our team’s effective collaboration also improved SNRC’s sustainability through the diversion of liquid food waste from landfills. This enhancement further fuels the facility’s biogas reactors and its overall power output. 

Consider the Birds (and Flowers, and Kangaroo Rats)

Building Sterling Natural Resource Center also involved a high degree of sensitivity to local wildlife.

The area is home to large populations of the San Bernadino Kangaroo Rat, a gerbil-like rodent and the focus of extensive conservation efforts by the federal Bureau of Land Management and the California State Water Resource Control Board. Our team, in collaboration with the client, identified the ecological importance of this species early on and incorporated substantial mitigation measures into our designs and earliest GMP estimates.

Silt fences, rat fences and other deterrents helped ensure that kangaroo rat populations were repelled from the project site, thus avoiding any undue harm to a species already significantly affected by human development and community expansion.

The team developed creative solutions to protect other local wildlife, including the Santa Ana River woolly star flower, the silver-horned spine flower and the California gnatcatcher bird. Each is a federally designated endangered species, and each is a vital component of the local ecosystem. Effective preservation methods were part of our client’s mission, so we made it our mission as well.

Progressive Success

Sterling Natural Resource Center ultimately stands as a progressive design-build success story – a testament to the power of early collaboration, innovation and communication between a contractor and all stakeholders, and an experienced project team that can adapt to and overcome any number of unforeseen challenges, changing community needs and unique environmental considerations.

Under a progressive design-build methodology, all parties are equipped and empowered to thrive, innovate and achieve excellence.