Methodology for calculating the carbon footprint of underground utility projects

The utilization of traditional open-cut methods for the installation of underground utilities has been common practice in the construction industry for many years. Today, engineers are being tasked with the requirement of selecting a suitable construction method that not only offers the most economical solution, but also minimizes impact to the environment. Trenchless construction methods offer such solutions for installing new utilities and rehabilitating existing infrastructure. The use of multiple construction equipment during open-cut construction invariably results in considerably more emitted emissions into the atmosphere compared to employing trenchless methods, which have minimal on-site equipment requirements. Pollutants such as carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxide (NOX), total organic compounds (TOC), and sulfur oxide (SOX) are identified by the United States Environmental Protection Agency (US EPA) as being emitted from equipment engines. This paper describes a methodology for quantifying the carbon footprint of a typical underground utility project. A case study comparing trenchless pipe replacement and traditional open-cut is used to demonstrate the reduction in emissions by adopting trenchless technologies. Reducing emissions into the atmosphere is a vital step in developing sustainable solutions. These environmental considerations are critical in sustaining our environment for the benefit of future generations.