CARE Grant Case Study: GHD, Inc.

Posted on November 25, 2017


GHD, Inc. engineering firm, in partnership with Humboldt State University, received CARE grant funding to test post-consumer PET carpet for use in civil engineering applications. The work included testing of physical properties as well as testing water quality in contact with post-consumer carpet over time periods between two and six months. The feasibility study revealed three optimal civil applications for PET in the form of post-consumer shredded carpet or carpet fibers. These applications must undergo a Phase II pilot project study before California public projects are feasible.


Santa Rosa, CA and Arcata, CA


April 2016-March 2017 



  • Grant funding covered 100% of the project costs.


  • Designing new equipment for testing physical properties.
  • Trimming carpet into manageable sizes for testing and un-baling carpet fibers for testing.
  • Applications will be new and challenging to market, even if proven.
  • Post-consumer carpet will contain different materials depending on the environments with which it was in contact.
  • More testing is needed to support feasibility study.
  • Finding sources of data and projects similar to this project.  There is surprisingly little information relating to reuse of PET carpet fibers and material properties.  New applications usually require an understanding of the material in question, and finding the information is a challenge. If the data needed cannot be found, it must be developed. 


  • CARE technical assistance.
  • Partnership developed with complementary local university.
  • Funding for testing of more recycled products in the marketplace.
  • CARE connected project to researchers that had tackled similar issues with different material, or same material but for different applications.  Also connected project to a chemistry professional to explain chemical makeup of the material to help GHD define knowledge still needed.

“The CARE grant provided the means for us to develop a much better understanding of the (post-consumer carpet) material from a properties perspective as well as a platform for developing informed decisions regarding the direction of future work and market development.  This has helped us find potential outlets for a material traditionally very difficult to categorize and market.”

Joaquin Wright, Senior Project Engineer, GHD, Inc.


  • Securing new partnerships.
  • Examining existing research on PET carpet properties and its behaviors in civil engineering applications.
  • Securing all equipment/materials and experienced staff. To complete the feasibility study, the project used expertise from civil engineers, environmental engineers, chemistry engineers, construction managers and general contractors familiar with implementation of civil engineering projects.
  • Testing physical properties and quality of water leachate soaked with post-consumer carpet. Comparing water quality tests to California and national maximum contamination levels.
  • Drawing comparisons to recycled tire-derived aggregate.
  • Drawing conclusions regarding optimal civil applications for PET carpet and developing recommendations for next testing steps.
  • Writing draft and final reports.


  • Demonstrating the viability of more environmentally friendly recycled products.
  • A new level of knowledge gained on PET material properties and potential uses. There is now information on material components in various forms, which leads to a much better understanding of what type of products and/or applications may benefit from using different forms of recycled PET carpet.  This knowledge allows projects to look toward specific uses which will have a much higher likelihood of adoption in the marketplace and increasing the use of recycled PET content.

Visit our Post Consumer Carpet Products page.

Visit the CARE grants page. 

This is one of a series of case studies that illustrate the impact of grant funding on the carpet recycling industry in California.
CARE will offer a Cycle 2 round of grants to support capital improvements and product testing in late 2017. Sign up for updates here.