Balancing the Natural and Built Environment

An urban stormwater treatment project, the South Los Angeles Wetland Park sets the bar high for achievement in sustainability. More


As a recognized leader and longtime proponent of sustainability, we bring a truly holistic approach to our practice and our projects.

Our commitment is underscored by our:

  • Leadership in progressive environmental policy
  • Partnerships with government and civic organizations to promote sustainable programs
  • Delivery of infrastructure projects that balance the natural and built environment
  • Investment in the continuing education of our staff


ISI-chartermember-logo-250x338member_logo_grayPsomas is a founding member of the Institute for Sustainable Infrastructure (ISI) and played a key role in the development of ISI’s groundbreaking Envision™ rating system. Our Chairman Emeritus, Timothy Psomas, PE, is the founding chair of ISI’s Board of Directors.

Over 100 Psomas professionals have been credentialed through the US Green Building Council as LEED APs or through ISI as ENV SPs (Envision Sustainability Professional).

Learn more about Psomas’ sustainability expertise and activities

Select Sustainability Projects

South Los Angeles Wetland Park
Los Angeles, CA

The South Los Angeles Wetland Park, which was awarded the Envision™ Platinum rating by the Institute for Sustainable Infrastructure, transformed a nine-acre former rail transit yard into a public green park space. The wetland captures and treats urban runoff from the 525-acre surrounding watershed, at the same time adding precious green open space and a nature experience to the inner city.

The WELL at CSU, Sacramento
Sacramento, CA

Campus Wellness in a Sustainable Building: Psomas provided civil engineering services for this new campus recreation/wellness center, known as “The WELL.” The project achieved LEED® Gold certification, joining a shortlist of LEED-certified recreation buildings in the CSU system.

Kaiser Permanente Antelope Valley
Lancaster, CA

Psomas provided civil engineering and surveying services for both the master planning of this 44-acre greenfield site as well as development of the first medical office. The project is LEED® Gold Certified.

Rory Shaw Wetlands Park
Los Angeles County, CA

Psomas is the prime consultant to transform a former 46-acre landfill into a multi-purpose stormwater management facility. Recently awarded Envision™ Platinum by the Institute for Sustainable Infrastructure, it serves a multitude of purposes: flood control, stormwater treatment, groundwater recharge, nature preserve, and active park.

University of Utah Geology and Geophysics Building
Salt Lake City, UT

The $25-million Sutton Geology and Geophysics Building serves as the University’s icon for green building design for its various sustainable and innovative designs. Psomas provided civil engineering and land surveying for this state-of-the-art facility including documentation for the building’s LEED® Gold certification.

CalSTRS Headquarters
West Sacramento, CA

This 15-story office tower utilizes the latest sustainable design techniques and is certified LEED® Gold for New Construction and LEED Platinum for Existing Building Operations + Maintenance. Psomas provided civil engineering services from conceptual design through final construction as part of the design-build team.

Next Section: Awards

Contact Kevin
Kevin Thornton, PE, ENV SP
Sustainability Director

Sustainable Development
“Development that meets the needs of the present without compromising the ability of future generations to meet their own needs."

Source: The Brundtland Commission

Psomas' 2017 Sustainability Report