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Re-evaluating Vermont’s Stormwater Infrastructure in Light of the 2011 and 2023 Floods

Co-Authored by Tyler Barnard, EV Civil Staff Engineer

Every four years the Vermont Section of the American Society of Civil Engineers (ASCE) publishes the Infrastructure Report Card. It serves to educate the public and elected officials on the status of Vermont’s infrastructure using a graded scale from A, to F. The reporting on condition and critical need is an indispensable asset, and in light of the recent flooding events affecting Vermont communities, we feel it is important to champion this work.

The 2023 Report was released in February of this year. Across the board, it praises government spending on the American Rescue Plan as an effort to make our state more resilient to future storm events.

Tyler Barnard from our civil engineering department co-authored the Stormwater Section of the 2019 and 2023 Report Cards. He, along with other authors are volunteer members of the ASCE Board of Directors and members of the community.

They dedicate time and resources to this report, which is used by community leaders to better prioritize limited funding. Overall, this helps to improve the condition, capacity, operations, maintenance, safety, innovation, and resilience of critical infrastructure.

The 9 Infrastructure Categories

• Aviation
• Bridges
• Dams
• Drinking Water
• Energy
• Roads
• Solid Waste
• Stormwater
• Wastewater

Stormwater and Climate Resilience

Stormwater scored a D+ in 2019, and C- in 2023. While things are improving, anything in the C range is considered “Mediocre: Requires Attention.”

“The infrastructure in the system or network is in fair to good condition; it shows general signs of
deterioration and requires attention. Some elements exhibit significant deficiencies in conditions and
functionality, with increasing vulnerability to risk,” – Vermont’s Infrastructure Report Card

Historically, stormwater control and treatment has been lower on the public’s priority list than the roads we commute on and the quality of the water we drink. However, it has quickly jumped to the front of everyone’s minds as climate change affects weather patterns and rainfall events, and we brace for future floods. So what can we do to help ease climate concerns, and boost resilience?

Solutions to Raise the Grade

The following is pulled directly from the 2023 report.

VT-ASCE makes the following recommendations to raise the grade of Vermont’s stormwater:

• Establish a state budget committee to effectively define and fund short-term and long-term needs.
• Establish scale-appropriate clean water utilities at the municipal level that provide a consistent and dedicated labor force for stormwater management improvements and maintenance.
• Establish an easily accessible statewide system that inventories the size, condition, capacity, procedures for operations and maintenance, and capital needs of all public and privately-owned stormwater assets.
• Improve stormwater infrastructure through retrofit of older systems that provide minimal water quality benefit and continue to embrace innovative water quality treatment practices for future new development and redevelopment.
• Fund research in stormwater management and treatment technology to improve water quality and reduce capital expenditures. This includes exploring options to address maintenance and monitoring of stormwater infrastructure, whether public or private.
• Develop additional funding sources for stormwater, GSI, and LID projects.

The full report goes in depth on the condition and capacity of existing stormwater infrastructure, how the state and municipalities are operating and maintaining their networks, and future funding and needs (pages 67-73). The full report can be found at: https://infrastructurereportcard.org/state-item/vermont/

2023 ACEC Vermont Engineering Excellence Awards Merit Recipient: Water Resources

The City of South Burlington has long aspired to have a city center that promotes prosperity, nurtures growth, and anchors their community. After years of planning the South Burlington City Center is now a reality. At the core of this new downtown is the recently completed municipal building that combines City offices with a library and community center. This new building provides an activity hub for the community and is designed to tie together the adjacent residential, educational, and commercial uses along the newly reconstructed Market Street.

The initial challenges presented were space limitations and unusual phasing issues. Allard Square had recently finished construction for their underground parking access, which ran directly through the library’s site. In addition, the traffic flow and circulation for the elementary school would be impeded if they weren’t given due consideration. This required working with adjacent property owners and the Market Street team to find solutions and make adjustments in real time. For Allard Square, we were able to work with their staff and the City to route a new connection to the garage level.

Similarly, the primary access drive to Marcotte Central School ran through the building footprint, requiring a new route. The project also required parking and stormwater treatment on school property to the north. This required parking lot changes and replacement of an existing stormwater system. Working with the school district and City staff we were able to reconfigure parking and driveways to maintain the same number of parking spaces and to improve circulation for the school. We were also able to design stormwater systems that exceeded requirements of both the City and State while bringing the school site close to compliance with the upcoming 3 AC stormwater requirements.

Systems for stormwater treatment and flow control were challenging for this project due to these tight site constraints as well as the need to replace existing storm systems and manage both pre and post construction discharge to Market Street. Although soils on site were sandy, groundwater depths prevented the use of infiltration-based systems for water quality treatment. To tackle this impediment with minimal impact on the adjacent elementary schools’ operations we designed and implemented five high-rate biofiltration systems. These treated surface runoff and allowed stormwater to be fully treated above the seasonal high-water table. The treated runoff then flowed to one of two large underground storage galleries. This new system enabled us to provide groundwater recharge without relying on filtration in the underlying soils.

Coordination of the project design with adjacent stakeholders required ongoing communication and working with their project teams. Our solutions were designed to satisfy the needs of these neighbors while also meeting the project’s objectives. This level of communication and collaboration made our typically invisible role as site engineers central to the discussion, enhancing everyone’s understanding of how these elements are interrelated. In addition, the project location – central to the new downtown and elementary school makes these stormwater systems highly visible to city residents.

This project demonstrates a way to fit and retrofit high value stormwater treatment and groundwater recharge onto a site with a minimal surface footprint while also providing a high level of storage and flow control. The project location – at the new city center and next to a library and elementary school makes these systems highly visible to a large portion of City residents, including overviews from the new building. The proximity to the school itself offers educational opportunities.

In July of 2021, this facility opened to the public. The original RFQ indicated that this was to be a “catalyst project”, and to provide a central gathering place for residents.  Given the rate of construction on Market Street and the amount of use seen by this new building, those goals have been achieved.

Two of EV’s administrative team went on a snowy tour of 65 Oakledge. Meg Dowling and Katherine Rudzki were led by Bob Neeld through this single-family home. It is the size of a medium commercial building.

First stop was through a makeshift doorway into the garage. The team wandered through halfway finished hallways, stepping over tiny canyons that will hold radiant heat tubing. From the garage, they found themselves in a grand entryway.

From there, the team walked into what will be the dining room. It is here that one can see what EV’s team of structural engineers can do. There are steel beams visible going up and over the room. These beams are holding up the building, and they also cantilever outward towards the lake to create a deck. This is an elegant way to incorporate the structural elements of the building into a physical element of the building.

The team moved upstairs to check out just how sturdy the second floor might be. Bob identified an area of the floor on top of a steel beam and told Meg and Katherine to jump on it. The floor had no give whatsoever! That’s the power of structural engineering!

Our Financial Systems Manager, Meg, was thrilled to see what the inner workings of such a big house would look like. For projects like this, she only sees the outcome of billing and invoices. Katherine, EV’s Marketing Coordinator, was excited to see just what structural engineering looks like in a home. So many of her project photos are of the completed building, most of the time she can’t point out from the outside what her coworkers have done.

The team are excited to see what the completed building looks like!

Two EV projects won Efficiency Vermont Best of the Best awards at their Better Buildings By Design conference. The Pierson Library (Vermont Integrated Architecture) in Shelburne, Vermont and the Worthen Library (Wiemann Lamphere) in South Hero, Vermont both won awards for energy efficiency.

According to a recent Gallup poll, library attendance has outpaced trips to the movie theater over 2019. In a parallel trend, libraries all over Vermont are getting makeovers. On top of these two buildings, South Burlington, Vermont will soon have a new combined community center, city hall, and library of their own.

The Pierson Library in Shelburne was given both the Large Commercial Honor Award and the People’s Choice Award (chosen by conference attendees). The old building was torn down to construct a modernized and energy efficient library. It opened in September 2019, and since then the library hours have expanded to keep up with demand.

The Worthen Library in South Hero used to be located in the town’s elementary school. Because of this, its hours were dictated by when the school was open. Town leaders wanted the facility to better service the community with extended hours, and to have the capability of becoming net zero in the future. The new library accomplishes exactly that! This library was given the Small Commercial Honor Award at the Efficiency Vermont conference.

Engineering Ventures is proud to be a part of the future of energy efficiency in Vermont!

On Sunday September 29, 2019 the sun was shining and the air was crisp in the mountains around Stowe, Vermont. The early fall foliage was rustling in a light breeze. All was calm and peaceful. But, not for long! The field behind the Stoweflake Mountain Resort was preparing for a bombardment of epic proportions.

Building and Testing

A team of Civil Engineers and Admin at EV got together to build and fine-tune a trebuchet for the Vermont Pumpkin Chuckin’ Festival. Over the course of two weeks, Tyler Barnard, Julia Ginorio, Paul Boisvert, and Katherine Rudzki built a “walking arm” trebuchet. A physics teacher in Vermont, Mr. Jonathan Stapleton, developed this style, and he competes in this festival with his son every year using his design. Though the walking arm trebuchet looks almost nothing like what might have been used centuries ago, it is effective at flinging pumpkins farther than most other styles of similar weight classes.

Team EV developed a few modifications to the original trebuchet design including enforcing the corners of the triangle with struts and staggering the weight towards the rear of the arm. These modifications would ensure the triangle wouldn’t break easily upon impact and the arm would have more power during its follow-through swing. Other than that, it was just a matter of fine-tuning the angle of impact and the weight before the competition.

Contest Day

On the day of the festival, the team arrived to set up their trebuchet and scope out the competition. There were the usual suspects – Mr. Stapleton and his son both sporting their walking-arm trebuchets, and a few others who have competed in years past. Despite the walking arm trebuchet endorsement in the official Vermont Pumpkin Chuckin’ Festival blog, there were plenty of other wild designs on the field!

Team EV decided on a name on the fly: Walker Texas Flinger, paying homage to the name of the trebuchet design. The first two throws were decent. The first went 160 feet, and the second flew into a stand of trees off to the side 220 feet. But, the last throw put EV on the map! After shuffling around weight on the arm more towards the rear, the projectile flew an incredible 290 feet!

At the end of the day, EV won 2nd Place in their weight class, and 3rd Place overall!

Will Team EV fine-tune their design for next year’s competition and beat their own record? Stay tuned!