An innovative public-private partnership creates an affordable source of ‘new water’ – unlocking new ways to nurture desert communities and conserve the world’s natural resources.
Set amidst the Sonoran Desert, North America’s hottest desert, water in Pima County, Arizona is a vital yet sparse resource. The Lower Santa Cruz River supports desert life, replenishes the region’s drinking water supplies and is playground to residents and visitors alike. Protecting this valuable resource is a key priority for the Pima County Regional Water Reclamation Department.
Because traditional project delivery couldn’t meet the County’s regulatory deadlines to improve its effluent and protect river water quality, they selected CH2M to help implement an advanced water reclamation facility using the design-build-operate delivery model. Driven by an unwavering commitment to success, CH2M and Pima County forged a lasting partnership, while working with local businesses, residents and stakeholders every step of the way.
Together, the integrated team unveiled an industry-first wastewater treatment process, saving taxpayers millions of dollars, augmenting precious water supplies and setting a new standard for delivering critical infrastructure projects under the watchful eye of regulators and stakeholders.
Design and delivery strategies saved the County $77 million
Reduced annual operating costs by $2 million
Delivered 8 months early and 1 year ahead of regulatory deadlines
Innovative design reduced Agua Nueva’s footprint by over 75%
CH2M’s performance was excellent on all fronts. Their delivery methodology was founded on a true spirit of partnering, implemented in the earliest project stages and sustained throughout delivery.... We are very pleased with project results – a project delivered $2 million below the final contract value and completed 8 months early.”
Meet the team
You can walk onto our projects and you cannot tell me who is from engineering, construction, operations or outside consulting and contracting firms.... It’s truly a wonderful thing to see.
CH2M’s technology group genuinely cares about the success of each other, and we have a lot of fun tackling seemingly uncrackable challenges together.
When we develop and implement the technology necessary to improve water quality, we’re directly impacting the everyday lives of people in the area.
I consider myself one of the lucky ones because I get to work on some of the coolest projects in the world.
Our design-build-operate model encouraged collaboration and innovation throughout the project, delivering innovative technologies and creative solutions to challenges, ensuring a highly successful project for our client.
What was involved?
As the single-entity designer, builder and operator, CH2M had complete responsibility for the project, from concept development through permitting, final design and construction to operations and maintenance for up to 20 years, realizing social, economic and environmental opportunities at each phase of our engagement.
Comprehensive design and construction capabilities solved the most difficult schedule, budget and technology challenges
Engaging operators at each step infused quality, efficiency and reliability into all activities
Technical excellence in wastewater, reuse and water reclamation is transforming the industry
Full-service water management capabilities supported total water solutions
Integrated service offerings provided a more sustainable and positive future for the community
Agua Nueva’s footprint is smaller than any facility of its kind – ensuring the least site and environmental impacts at lowest cost to ratepayers. Its landscaping and architecture boast colors and textures that mirror the desert’s enduring beauty, serving as a good neighbor to nearby residents and businesses. Promoting local economic progress, CH2M more than doubled its local small business participation goals, volunteered in the community and hired County operators to operate the new plant, providing new jobs and opportunities in Pima County and CH2M.
Re-engineering water reclamation: The Agua Nueva Water Reclamation Facility
Engineers, builders and operators work hand-in-hand with Pima County to solve this desert community's water resource challenges
Growing populations, stricter regulations, constrained water resources and small pocket books have cities and municipalities looking for smarter ways to build wastewater treatment plants. Pima County’s Agua Nueva Water Reclamation Facility is a great example for how collaboration across the entire project lifecycle can forge deeper relationships and a unique teaming environment – setting the ideal stage for envisioning and unveiling an industry-first wastewater treatment process that saves taxpayers’ money while augmenting critical water supplies for desert communities.
Because compliance schedules could not be met using conventional project delivery, in December 2010 the County selected CH2M to design, build and operate (DBO) the program’s crown jewel: the new $172 million Agua Nueva Water Reclamation Facility. Producing 32 million gallons of high-quality reclaimed water every day, its unique treatment process includes:
- New headworks
- Influent pumping
- Dissolved air flotation (DAF) clarification for primary treatment and sludge thickening, using the Evoqua CAPITVATOR™.
- 5-Stage Bardenpho activated sludge secondary treatment with step-feed aeration
- Tertiary filtration
- Chloramine-based disinfection
Crystalizing the team
Determined to help Pima County achieve its ambitions, CH2M tapped into its integrated service offerings, assembling a passionate team of engineers, designers, architects, builders and operators to deliver technical innovation across the entire project lifecycle. This provided a design process built around input from our construction and operations experts to address constructability and operability at all times – maximizing our collective focus on startup and operational efficiency. It also engaged our engineers and designers during construction and startup to avoid process interruptions and provide a smooth transition to long-term operations and maintenance.
Because this was the County’s first DBO project and we were implementing an unproven technology at full scale, partnership was an enduring theme throughout the project. Our formal partnering program unified the team around 14 guiding principles and leveraged the state of the art in collaboration technology – including advanced building information modelling (BIM), 3D visualization, site-wide cameras and video conferencing – engaging Pima County in key activities and decisions at all times.
Setting the stage
Concerned that wastewater discharged into the Santa Cruz River could affect local groundwater supplies, in 2006 Arizona regulators required that Pima County reduce the nitrogen in its wastewater by January 2015. To realize the most sustainable, community-focused solutions, the Pima County Regional Wastewater Reclamation Department embarked on the largest capital program in its history – the $720 million Regional Optimization Master Plan.
Together, the team broke new ground in water reclamation:
- Primary Treatment. Agua Nueva is the world’s first wastewater facility to use dissolved air flotation for primary treatment (Evoqua CAPITVATOR™) – creating an already thickened sludge ready for processing at significantly reduced costs.
- Secondary Treatment. Agua Nueva is North America’s first facility to integrate step feed with dissolved oxygen effluent ammonia control – optimizing disinfection, reducing chemical use and improving operational flexibility and reliability.
- Odor Control. The centralized biofilter system, together with the bioreactor’s dual-bed carbon absorption system, requires no chemicals and minimal attention – creating an affordable, odor-free environment for nearby residents.
- Control System. The fully automated system integrates all treatment components into an efficient, easy-to-operate facility – providing better process control, improved safety, lower operating costs and higher water quality.
The Agua Nueva Water Reclamation Facility was delivered $77 million below the County’s $240 million design-build budget, 8 months early and 1 year ahead of the compliance schedule, saving $2 million in annual operating costs. All team members made it home safely each and every night, delivering over 1 million man-hours with no lost time injuries.
The County can now maximize the use of its high-quality reclaimed water to irrigate parks, golf courses and other turf facilities, reducing the diversion of water from its sensitive habitats. And with significantly reduced nitrogen levels, water discharged into the Santa Cruz River is safe for aquatic and civic life alike – with restored flora and fauna already returning to the river.
Testament to its importance to the future of water reclamation, the project has received 11 industry awards for its engineering excellence and best practice delivery approach.