photo of green infrastructure

ASCE has released a first-of-its-kind standard, ASCE/COS 73-23: Standard Practice for Sustainable Infrastructure, which provides guidance for infrastructure owners to develop and implement sustainable solutions throughout a project’s entire life cycle.

The standard is a non-mandatory, performance-based consensus standard designed for civil infrastructure ranging from transportation projects to water systems and the energy grid.

“Building the right project beyond building the project right has been top of mind for us engineers,” said Cris Liban, D.Env., P.E., Dist.M.ASCE, chief sustainability officer for the Los Angeles County Metropolitan Transportation Authority. “ASCE 73-23 provides the performance standard wherein anyone around the world who wants to design, build, maintain, operate, and procure sustainable and resilient infrastructure can now have the standard to reference.

“Implementation of this framework by policymakers, infrastructure owners, and practitioners will promote mitigation and adaptation toward environmental threats, provide innovative alternatives to current construction practices, and minimize long-term costs over a project’s entire life cycle.”

Liban served as the chair of ASCE’s Committee on Sustainability five years ago when the process to develop this standard began. The ultimate document was a product of a diverse group of stakeholders led by the ASCE Committee on Sustainability Sustainable Infrastructure Standards Committee. 

“We envisioned a standard that would not dictate the how, but instead empower the who and influence the outcomes, especially for those whose resources may be limited,” Liban said. “This ensures that sustainable infrastructure is built equitably and addresses the specific needs of communities that build them. This standard is our legacy to those who will inherit the new infrastructure practice and paradigm.”

The standard’s performance-based approach to sustainability is intended to:

  • Allow for implementing sustainability strategies on a project-by-project basis.
  • Involve the project owner in establishing the “triple bottom line.”
  • Facilitate the use of rating systems or other tools to measure the sustainability of the project.
  • Encourage creativity and innovation in the design and construction community.
  • Allow for optimizing any conflicting environmental, social, and economic requirements of the project.

ASCE 73-23 also focuses on reducing embodied carbon, which refers to the greenhouse gas emissions stemming from the entire process of transporting materials, constructing, operating, and maintaining an infrastructure project. The standard directs project owners to develop and implement a greenhouse gas emission reduction plan to reduce the total infrastructure solution emission by 15%from the solution’s baseline.
The standard complements existing ASCE standards and tools like the Envision rating system. The Envision 3.0 rating system for sustainable infrastructure can be used as a tool to measure achievement of sustainability goals. The Institute for Sustainable Infrastructure, founded by ASCE in partnership with ACEC and APWA, participated in the development of the standard.

“We now live in a world where collaboration and coordination are necessary to accelerate our journey towards achieving sustainable and resilient infrastructure,” Liban said. “ASCE 73-23 provides the avenue for owners, engineers, and practitioners to reach out to one another and to others, especially to unconventional infrastructure partners. That can spark a new way of infrastructure thinking.

“This standard was simply an idea that began almost a generation ago. We found a new sense of urgency in 2018, and we finally made it.”

The standard is available for preorder now. An eBook will be available in the ASCE Library Oct. 20. 

The ASCE INSPIRE 2023 Conference, Nov. 16-18 in Arlington, Virginia, will include a session examining and discussing ASCE 73. Copies of the standard will also be available at the conference.