Z-rating System for the Sustainability of Infrastructure Projects

Summary

The Zofnass Program’s first research project resulted in the Z-rating System. A toolkit for the various stages of an infrastructure project. The intention has always been the selection of the best and most suitable type of project solving the problem at hand. After three years of intensive collaboration between academia and the industry the system was given to the newly established Institute for Sustainable Infrastructure (ISI) and was renamed Envision®. The research continued after that, to enhance the rating system. Z-rating System separated the aspects that define the sustainability of a project. These are:

Hover over the icon titles to learn more about each aspect of the Z-rating System

Quality of Life Quality of Life addresses a project’s impact on surrounding communities, from the health and wellbeing of individuals to the wellbeing of the larger social fabric as a whole. These impacts may be physical, economic, or social. Quality of Life particularly focuses on assessing whether infrastructure projects are in line with community goals, incorporated into existing community networks, and will benefit the community long-term. For that purpose, community involvement should be sought by infrastructure owners. Community members (both users and non-users) affected by the project should be considered important stakeholders in the decision-making process (during design as well as during operations). The category is further divided into three subcategories: Purpose, Wellbeing, and Community.

Leadership Successful sustainable projects require a new way of thinking about how projects come to life. Project teams are most successful if they communicate and collaborate early on, involve a wide variety of people in creating ideas for the project, and understand the long-term, holistic view of the project and its life cycle. This section encourages and rewards these actions under the view that together with traditional sustainability actions, such as reducing energy and water use, effective and collaborative leadership produces a truly sustainable project that contributes positively to the world around it. This section is divided into the three sub-sections of Collaboration, Management, and Planning.

Climate & Resilience/Risk The general scope of Climate and Resilience/Risk was two-fold; to minimize emissions that may contribute to increased short and long-term risks and to ensure infrastructure projects are resilient to short-term hazards or altered long-term future conditions. The Climate and Resilience/Risk category is divided into two sub-categories: Emissions and Resilience.

Resource Allocation Resources are the assets that are needed to build infrastructure (construction) and keep it running (operations). This category is broadly concerned with the quantity, source, and characteristics of these resources and their impacts on the overall sustainability of the project. Resources addressed in this rating system include physical materials, both those that are consumed and that leave the project, energy for construction, operation, and maintenance, and water use. Each of these materials is finite in its source and should be treated as an asset to use respectfully. Materials, Energy, and Water comprise the three subcategories of Resource Allocation.

Natural World Infrastructure projects have an impact on the natural world around them— the habitats, species, and non-living natural systems. The way a project is located within these systems and what new elements they may introduce into a system can create unwanted impacts. This section addresses how to understand and minimize negative impacts while considering ways in which the infrastructure can interact with natural systems in a synergistic, positive way. These types of interactions and impacts have been divided into the three sub-categories of Siting, Land and Water, and Biodiversity.

All five aspects are individually rated in order to be able to identify the project’s sustainability in each section. The sum of the individual ratings provides the total sustainability rating of the project.

The Envision was launched in 2012 to fill a gap for a holistic rating system for sustainable infrastructure and today constitutes the standard in the US for rating the sustainability of hard infrastructure. While sector specific systems exist, (e.g., roads, ports), Envision® is an overarching tool that covers all aspects of infrastructure.

It can assess sustainability for civil and private infrastructure projects of all types, sizes, complexities, and locations in their planning, design & construction, and operation & maintenance phases. It sets the standard for what constitutes sustainable infrastructure; incentivizes higher performance goals beyond minimum requirements; gives recognition to projects that make significant contributions to sustainability; and provides a common language for collaboration and clear communication both internally and externally.

Further resources

Also available:
Institute for Sustainable Infrastructure – Envision®

Research team

Program & Research Director
Prof. Spiro Pollalis, pollalis@gsd.harvard.edu