SLR receives 2020 Engineering Excellence Award for Design & Construction

The American Council of Engineering Companies (ACEC), Vermont Section recently announced SLR as the recipient for the 2020 Engineering Excellence Award for Design and Construction of the Shelburne Community School Raingarden project. The annual award showcases exceptional engineering projects completed in Vermont.

The project was completed by Milone & MacBroom which is now a part of SLR and completes engineering design and technical advising for Lewis Creek Association’s Ahead of the Storm (AOTS) program that helps communities improve the way stormwater is managed on properties to reduce polluted runoff from large rainstorms. The AOTS program included both design and construction of demonstration projects and an education program for communities and schools. SLR teamed with Lewis Creek Association, a local watershed group to design and construct a stormwater treatment raingarden to filter runoff from nearly 1 acre.

With the raingarden project strategically located in the front entrance of Shelburne Community School (SCS) where it is highly visible, project engineers partnered with SCS staff and students to create a complementary teaching curriculum that includes stormwater runoff, stormwater treatment, flood resiliency, water quality, and information about the local watersheds of McCabe’s Brook and Lake Champlain. This academic program was piloted by SLR’s water resource engineers during this project and will be used by students and teachers to provide learning experiences aimed to inspire future generations to improve and protect water quality. Students will be monitoring the raingarden performance and effectiveness and participating in annual maintenance of the raingarden.

“This project will serve as a model for three additional projects across the school district and can be used by others in the future,” noted Jessica Louisos, MS, PE Lead Project Engineer, Water Resources. “This combined education and treatment model is especially applicable to Vermont schools at this time as many schools such as SCS will need to comply with the new 3-Acre Stormwater Permit to create stormwater treatment retrofits to treat runoff from existing impervious surfaces.”

Project Background – A raingarden (stormwater treatment bioretention area) was designed and constructed in June of 2019 to treat runoff from a portion of Shelburne Community School’s (SCS) entrance driveway, sidewalks, parking, and lawn areas. The project treats runoff, reduces erosion, and enhances vegetation where water previously traveled by pipe to McCabe’s Brook and to Lake Champlain. The project was identified as the best way to improve water quality leaving the school property during a site assessment completed by water resource engineers, school staff, and fifth grade students. A novel aspect of this stormwater treatment project is that a local watershed group non-government organization is facilitating water resource engineers to work directly with elementary school students to identify and design a water quality improvement practice that will remove phosphorus from runoff and establish an outdoor classroom site for learning about stormwater runoff and treatment. Click on the following link to view the Shelburne Community School Raingarden Poster.

The constructed project met the goals of the client to remove phosphorus from runoff, increase flood resiliency, minimize cost, limit maintenance needs, and create a demonstration project that can be used for ongoing education and outreach. Despite site constraints from fine-grained soils, limited space, and underground utilities, the design maximized phosphorus removal and therefore the benefit to McCabe’s Brook.

Project Approach – A two-cell approach was used to avoid disturbance of underground utilities. Soil investigations showed limited infiltration capacity and an underdrain was included to drain stormwater after it passed through the supplemented soil filter layers. This project was designed to help the school comply with future stormwater treatment requirements for the new 3-acre rule.

The design specifically minimized maintenance needs and was coupled to existing onsite drainage infrastructure to minimize construction costs. Although the engineering for this project was completed on time, the project schedule was extended due to the need to complete construction during school breaks. Project costs were kept within available school and grant budgets using in-kind work donations from the Town and donations of plants and planting time from school students and their families.