More splashy, less gassy.
New sustainability checklist lowers carbon emissions and integrates other eco-friendly principles into project design, construction
The Sewer District is a perennial work in progress as we manage the upkeep of existing facilities, introduce innovations, and build new structures to ensure we operate as effectively as possible on behalf of our customers and the region.
Our projects are massive and diverse. We are increasing capacity at our wastewater treatment facilities; building huge tunnels to capture combined sewage (raw sewage plus rainwater) during wet weather; and taking on green infrastructure projects to manage stormwater, preserve ecosystems, and improve quality of life across our communities.
Doing good, well
But construction can exact a toll on the environment. According to the United Nations Environment Programme, the buildings and construction sector contributed 37% of worldwide energy and process-related carbon dioxide emissions in 2022.
Our Engineering & Construction team has always prioritized building the most efficient structures and systems possible, which reduces cost and resource use. But they recently took a huge step forward in shrinking the Sewer District’s carbon footprint and boosting our sustainability practices overall by developing an innovative checklist for project design and construction with the help of our Sustainability team.
Checking the list
E&C is using the checklist to identify, track, document, and implement sustainable design opportunities at every stage of project development and implementation. The list incorporates multiple categories.
- Energy Conservation focuses on the use of electricity and natural gas.
- Environmental addresses emissions (of CO2 and other air pollutants); stormwater management; and preservation/enhancement of biodiversity and green space attributes, among other things.
- System Resiliency and Adaptability looks at providing maintainable and expandable infrastructure and increasing treatment, service, and system capacity.
- Material Reuse, Recycling, and Reduction considers how to cut down on the use of resources, such as concrete and potable water, increase the reuse of materials, and extend their life.
- Community targets reducing impacts at construction locations by aiming to minimize noise and disruptions like light pollution, odors, and traffic congestion.
Piloting the list
To date, the checklist has been piloted in the design and implementation of three projects. One of them — a 3.5-mile, 23-foot diameter tunnel slated for completion in 2028 — will reduce annual Combined Sewer Overflows (CSOs), keeping around 760 million gallons of untreated wastewater out of the Cuyahoga River every year.
E&C shaved more than $18 million off the tunnel’s construction cost by optimizing the preliminary design and applying sustainability principles.
For example, the team’s decision to use a submersible pump station allowed the 200–foot-deep dewatering shaft’s original 80-foot diameter to be shrunk to 65 feet. This delivered the largest single element of cost savings and biggest boost in sustainability, reducing the use of concrete (by 2,500 cubic yards) and rebar (by 63 tons).
In addition to trimming more than $8 million from the budget, the Sewer District avoided emitting over 1,700 metric tons of carbon dioxide equivalent, comparable to the greenhouse gas emissions generated by driving a gas-powered passenger vehicle nearly three-and-a-half million miles (per the EPA’s Greenhouse Gas Equivalencies Calculator).
Taking the list District-wide
Using the checklist on three pilot projects enabled the Sewer District’s Engineering & Construction team to test it under real-world conditions and hone and adapt it to meet our unique needs.
E&C now plans to utilize the sustainability checklist in every project moving forward.
