Sustainable Civil Design, High-Impact Choices (Without the High Price Tags)
Better Data, Better Decisions
We are so lucky to live and work in the Pacific Northwest, where there’s a culture of care and sincerity around making choices that are right for the city, community, and earth. We don’t take this for granted! Far beyond being open to sustainability as a principle, the majority of our clients and partners are pushing the envelope and setting aggressive sustainability goals for their projects.
This theme is in no way isolated to our civil group. Our structural team is experiencing the same momentum, and as a firm, there’s been a huge push to deliver against client needs and remain at the forefront of sustainability concepts and trends. The challenge to keep pace with a forward-thinking industry and our complementary disciplines is a positive one!
All of the energy around sustainable design is exciting, and as engineers, it’s our role to complement that energy via education and serve as strategic, proactive team members. We don’t want to only talk about sustainable solutions, we want them to show up on projects everywhere and become celebrated pieces of sites and structures! We want to be able to contribute to these conversations, knowing that civil can have a significant impact.
The many sustainability-centered conversations we’re having with clients and partners led us to develop a decision matrix. Currently in development, the matrix is a tool designed to guide those conversations. If a client names sustainability as a priority, we can work through the matrix, identifying the lower and higher price tag items that a project could choose from. Each project and program is unique, so having the ability to pick and choose the sustainable options that are the best fit (and do so in an organized way!) allows for customized, effective final designs.
Our civil group is very detail-oriented by nature and we get excited by things like new equations and tools that yield better numbers. For example, we have a tool that calculates required pavement thickness for a desired life cycle. Instead of relying on typical numbers or past standards, we’re now able to input exact site specifics to create final numbers. No extraneous asphalt or concrete, and a reduced carbon footprint. It’s tools like this that inspire more and more investigation.
“Often, the assumption is that sustainable choices are costly and complicated. It’s our job to help project partners overcome this thinking and share solutions that make sense for the site, programming and lifecycle of the project.”
– Jackie Sempel, Civil Associate
Sustainable Materials and Measures: Our Civil Short List
1. Warm Mix Asphalt
The burning temperature of warm mix asphalt is lower than that of hot mix asphalt, which in turn, lowers the carbon created during production. It also improves onsite conditions, as there are lower emissions of fumes, aerosols and odors at the plant and work sites.
Our team is currently exploring studies to quantify differences, improvements, and increases.
2. Long-Term Planning
Asphalt versus concrete is a simple example of how lower price tags don’t always yield long-run savings. Asphalt is cheaper than concrete upfront, but after one (inevitable) replacement, the numbers start to match up. It only takes about 8-10 years to break even, at which point, owners may regret dismissing the superior (more expensive) option. Encouraging the project team to have a vision for the lifecycle of the site or campus can make a huge difference.
3. Rainwater Harvesting
Bioretention is required in Seattle and Low Impact Development (LID) techniques are required by code, but there’s such a huge spectrum of what you can do with rainwater and runoff. Imitate nature’s way, contain it onsite and make use of it, showcase it as a project feature. No matter what the choice, we always strive for low impact.
It’s difficult to generalize about savings, since implementation is site dependent. Exact numbers will depend on soils, siting and building type. The amount of rainfall you contain and they way you retain it is scalable too, so there are options for commitment levels.
4. Location, Location, Location
Turns out the real estate adage applies to civil solutions too. As the public becomes more interested and more aware of sustainability, we continue to see civil systems featured prominently in site design (instead of being hidden or tucked away somewhere onsite). As civil engineers, it’s a trend we love. Show off those rainwater harvesting systems! We know there’s value for owners in responding to community interests. Sustainability is a story the public wants to hear about, learn about, and experience, so it’s something worth investing in.
5. Low Carbon Options
Already in use in British Columbia and California, low carbon concrete (or carbon neutral concrete) is an exciting development in the world of concrete.
And yes, while this list primarily emphasizes low-cost options, low carbon concrete is an ultimate premium, doubling the cost of a program’s concrete. But, it belongs on the list as we explore different technologies and what’s available in our region.
It’s my belief that it will only take a handful of clients committing to it and working through the process of installing it locally before it takes off.
And we’re already seeing progress in that direction! For example, in partnership with Skanska, we’re exploring the use of a new carbon-reduced asphalt being used in Sweden. We’re reviewing the Swedish Recycled Concrete Aggregate (RCA) specifications, contrasting them with our own WSDOT standards, to see how we may be able to save on carbon and help DOT push the envelope.
Key to Sustainable Success: Internal Energy + Alignment
Tactics and specific solutions aside, an important consideration for leadership groups is to consider how they’re communicating these efforts to their teams. Success in the sustainability realm isn’t only about reframing the conversations for clients and partners, it’s about making education and innovation priorities in your office.
We’ve had a lot of success at Coughlin Porter Lundeen through simple sharing. If a project is doing something groundbreaking, talk about it! We’re lucky that our group is full of curious team members who really want to know! We’re constantly sharing articles and tidbits, and by extending these shares to both the civil and structural groups, we have a more cohesive energy.
As Co-chair of our Sustainability Task Group, it’s rewarding to see this collaboration at work. Company task groups help us stay on top of trends and industry happenings. As we collect information and have new things to share, we host Lunch and Learns for the full office. Our team is also encouraged to continue learning by taking advantage of conferences and seminars, which I love!
And perhaps our most important puzzle piece: we pay special attention to younger engineers. We make time for teaching and a part of that curriculum is encouraging young engineers to think differently. In this case, differently means long-term and big-picture. Asking questions like: What does long-term maintenance look like? How often does this item need to be replaced and what is the cost? What are the long-term benefits of this choice?
An Exciting Time for Sustainability
Our region is progressive, with projects adopting new technologies and solutions, and an overall movement toward a better built environment. The right team can focus on sustainable options that are in budget and implement a strategy for making the right choices for a site and project. There are so many options for today’s projects, it’s an exciting time for sustainable design!