The Important Role Contractors Play in Achieving Sustainable Outcomes for Infrastructure Projects
Contractors play an important role in influencing the sustainable outcomes of infrastructure projects. One tool in their belt is Envision, a planning and design framework launched in 2012 by the Washington, D.C.-based Institute for Sustainable Infrastructure (ISI). To date, more than $34 billion of infrastructure has been verified or is going through ISI’s independent review process in which the sustainability attributes of infrastructure projects are validated by independent third-parties in the civil infrastructure industry.
During five years of applying Envision to billions of dollars’ worth of infrastructure, the industry has progressed significantly, with several lessons learned along the way. ISI has incorporated the lessons into the next version of Envision: Envision v3. For example, the industry’s understanding of resilience has grown tremendously, especially in the wake of hurricanes Katrina, Harvey and Irma. Envision v3 has incorporated a more advanced appreciation and understanding of resilience.
Envision v3 recognizes the role of the contractor in the delivery of sustainable infrastructure projects. Several construction-related credits have been included in the upgraded framework, including construction phase energy and water consumption, construction phase waste diversion and construction safety.
To date, many Envision-verified projects have achieved verification either at or after 95 percent of the design process has been completed. Under Envision v3, projects may earn final Envision verification and the appropriate award based on score—once it reaches 95 percent construction completion. This shift further emphasizes contractors’ role in helping facilitate the development and delivery of sustainable infrastructure.
For example, on one recently verified project, the Boston Landing Station in Massachusetts, the contractor developed an approach to improve worker health and safety outcomes went beyond what was called for in the design stages of the project. With Envision v3, that additional effort would be explicitly recognized and rewarded. On the same project, the contractor saw an opportunity to reuse the existing track ballast rather than replace it with new material that had been specified in the design. The contractor’s recommendation was accepted, thus eliminating the need for more than 11,000 tons of new material.
On another Envision-verified project, the Highway I-4 Ultimate Improvement project in Orlando, Fla., the contractor deployed state-of-the-art equipment monitoring technologies and software to reduce environmental impacts during construction. The contractor also:
- utilized SCI fuel management technologies to monitor fuel dispensing into each piece of equipment and tracked consumption to determine equipment performance;
- installed auxiliary air conditioning units on crawler cranes used on the project, leading to a 20 percent reduction of machine hours and fuel consumption; and
- proposed the reuse of demolished concrete as new aggregate for the project, thereby saving valuable resources.
These actions helped the project team achieve additional sustainability points during the Envision verification process.
Finally, on the Exposition Transit Corridor—Phase 2 project in Los Angeles, the contractor played a leading role in the identification and application of non-standard technology to minimize the impact of sound decibels and vibration levels that light rail trains emit through the track system while passing by the many sound recording studios in the area. The specialized track was constructed using spring elements under the floating track bed, allowing noise and vibration to dissipate horizontally across the track, rather than vertically.
These three examples clearly demonstrate the vital role contractors can play in achieving sustainable outcomes for infrastructure projects. The Envision sustainable infrastructure framework now explicitly recognizes this significant role with Envision v3, which has been extended to include construction-related impacts such as energy, water, waste and safety.