Seeing the bigger picture for 90 years

Since 1933, we’ve helped millions of people lead better lives through the availability of clean water – but our work is not done. While we reflect on our 90th Anniversary with pride and gratitude, we are fueled by this milestone to continue striving for an even better future for us all.

1942

John Carollo and team design first water treatment plant in El Paso, Texas, which is still in operation

1962

Designed the first desalination plant to serve as a U.S. city’s sole source of drinking water

1997

Carollo Research Group is created – pioneering and validating many innovations like UV disinfection and CFD modeling

2009

Completed a Bay Area WWTP renewable energy expansion, helping the agency become one of the first net energy-positive utilities in the world

2013

Performed water quality study for the first-ever direct potable reuse plant in the U.S., demonstrating for the first time that DPR is safe

2016

Carollo Cares community outreach program begins, inspiring a new generation of water professionals

2017

Water ARC^®, Carollo’s applied research center, is created, linking lab innovation to real-world application

2018

Employee Leadership Program begins – inspiring and empowering current and future leaders at Carollo

2020

Designed the largest earthquake resistant ductile iron pipe project in North America, providing additional safeguards for California’s water supply

2020-2021

Completed two award-winning projects for the production and reuse of renewable natural gas from wastewater (digester gas)

2021

Collaborated with an international team to evaluate AI and machine learning in making water purification more efficient

2022

Established 50th office and the first office outside the continental U.S. in Vancouver, Canada

picture of a water treatment facility from above

2023

Serving as Owner’s Advisor for the City of Houston’s 320 mgd water treatment plant expansion – the largest progressive design-build project in the U.S.

2023

Designing the El Paso Advanced Water Purification Facility — the first direct-to-distribution direct potable reuse system in the United States

You are a critical part of our 90-year story. See how.

Working Wonders with Water®

For more than 90 years, Carollo Engineers has been 100% focused on water and wastewater solutions. For our clients, this means expertise and experience that deliver improved performance, minimized risk, and capital reductions—helping you stay ahead of potential issues. For our employees, it means being a part of something that can change lives, and the world we live in.

Drinking Water

Innovating through focus.

When you do one thing, and do it well, amazing things happen. New thinking emerges. Ideas are born. When you partner with us, as a client or employee, you’ll find innovation comes standard. It’s not innovation for innovation's sake—we generate proven solutions that fit clients’ needs and budget, as well as inspire us.

Innovation

Experts in all that is water.

Because water is all we do, we put all our resources into your project. From drinking water and wastewater to water reuse and so much more, our breadth of expertise is comprehensive.

View our Expertise

Woman and girl watering plants in greenhouse

We care about our communities and planet.

Clean, safe water is a foundation for healthy ecosystems and thriving communities. Sustainability, education, charity, and a caring culture aren’t just words to us. They are what drive us every single day, igniting passion in our employees, customers, and our youth.

See How Carollo Cares

Is water your passion, too?

If so, consider joining our team. You’ll collaborate with coworkers who are the best and the brightest, challenge yourself on exciting work, and help build the best water consulting firm in the U.S.

Working at Carollo

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