University of Vermont
OP-22: Rainwater Management

The University of Vermont (UVM) has established a framework to implement practices and procedures to manage stormwater runoff and improve water quality. UVM’s extensive system of stormwater treatment facilities include green infrastructure and LID practices whenever the soils are suitable for infiltration. Most of the underlying soils on UVM’s Main Campus are glacial till on bedrock, limiting the infiltration potential.

UVM’s Main Campus is approximately 459 acres and is located in two different municipalities and in four different stream watersheds. The campus is in both Burlington and South Burlington, and is split between the Centennial Brook, Englesby Brook, Potash Brook and Winooski River watersheds. Ultimately these four watersheds discharge to Lake Champlain. The University of Vermont also owns properties outside of Main Campus that also have stormwater collection systems.

The University of Vermont has five large stormwater detention facilities to treat and detain stormwater (see attached Overall Campus Watershed Plan):

- North Campus (87.3-acre watershed)
- East Campus (82.6-acre watershed)
- Southwest Campus (53.4-acre watershed)
- Main Street Facility (26.9-acre watershed)
- Colchester Business Park (16 acres)

UVM has several areas with pervious pavement:
- Pervious brick pavers in front of the Waterman Building (85 South Prospect St.)
- Pervious concrete parking lot behind 150 Colchester Avenue on UVM’s Trinity Campus. These pervious concrete slabs (StormCrete) have void spaces to allow water to move through. Since this type of pervious concrete tends to be more sensitive to harsh winter conditions and is more susceptible to breaking and clogging, UVM is always looking for more durable alternatives.
- Pervious concrete in front of the UVM Greenhouse.
- Pervious pavers at the north end of Kalkin Hall near the ADA parking.
- Pervious concrete walkways along the eastern side of the Living/Learning Complex.

UVM has several intensive green roof systems on campus:

- George D. Aiken Center: The construction of this building included an extensive green roof system to study the performance of pollutant removal in a northern climate. The roof system includes eight different micro-watersheds, six with vegetated trays and two control sites without vegetation. Researchers decided to test native Vermont plants as well as the use of biochar, a carbon-rich soil additive produced without the creation of carbon dioxide emissions. The green roof is monitored by tipping buckets to test water absorption of the different mediums and the impact of each watershed on stormwater runoff.
- Dudley H. Davis Center: This is an 18,000 sf roof over the loading dock on the west end of the Davis Center. It was planted with a variety of drought-resistant grasses. The soil depth varies from 6 to 21 inches and can absorb between 12 and 42 pounds of water per cubic foot. The roof can hold up to 80 pounds per cubic foot, including the soil itself, the grasses, and stormwater.
- University Heights Complex: There are two small green roofs on the terraces of this complex.

Other UVM green infrastructure and LID practices:
- Votey Hall Rain Garden (48 Colchester Ave.): This rain garden was designed and installed by student members of the Vermont Chapter of Engineers Without Borders in 2006. The vegetated area slows and filters stormwater from the Votey Hall parking area and eventually drains into the City’s stormwater system. Eventually UVM Grounds took over maintenance and simplified this raingarden, preserving its functionality.
- University Heights Complex: There is a watercourse where rainwater is channeled between University Heights buildings and collected in a bioretention area, and recycled for gray-water usage. The watercourse flows under a semicircular gathering space near the bioretention pond.
- Stormwater from the Marsh-Austin-Tupper Residence Halls parking lot runs through a grassland swale into a constructed pond. This diverts water from running directly into the City’s stormwater system.
- Redstone Lofts: Small rain garden adjacent to the parking lot.

UVM LID Research Projects:

- UVM Bioretention Laboratory: East of Jeffords Hall, the UVM Bioretention Laboratory is a site of ongoing research investigating the use of “bioretention rain gardens” to detain and treat stormwater runoff from paved surfaces. These roadside gardens use soils and vegetation to slow the rate of stormwater flow, infiltrate runoff and rainfall, and capture pollutants before they travel downstream to Lake Champlain. Eight bioretention cells are being investigated for pollutant removal performance under climate change conditions. Water and soil samples collected from these gardens are analyzed for nutrients such as nitrogen and phosphorous, as well as sediments and heavy metals that wash off the road.

- Wood Chip Bioreactor Treatment System: A wood chip bioreactor treatment system, consisting of three pre-treatment tanks, two wood chip bioreactors, and one infiltration basin, was constructed at the Miller Research Complex in 2016. Runoff and leachate from an adjacent silage storage bunker is directed into the system. The pre-treatment tanks include two settling tanks and one aeration tank. The former allows for sedimentation of organic matter, while the latter is designed to allow for nitrogen transformations that will help maximize nitrogen removal in the bioreactors. During the summer and fall of 2017, sampling occurred at four points within the system in order to determine the efficacy of various treatment steps. Samples were analyzed for nitrate (NOx—N), ammonium (NH4+-N), total nitrogen (TN), soluble reactive phosphorus (SRP), and total phosphorus (TP) in order to compare inflow and outflow pollutant concentrations and loads. Results indicate that this treatment system significantly reduced nutrient loads in the runoff.

- Effects of Compost & Vegetation on Stormwater Treatment with Bioretention Cells: In June 2016, a stormwater bioretention system was installed at the Miller Research Complex, a dairy teaching and research facility comprising of 2.7 acres impervious area, and with uses associated with a working agricultural landscape, including movement of silage, manure, etc. Runoff from the surrounding landscape is captured in grass-lined swales and moves through a settling forebay before it is split among three bioretention cells, each with a unique soil or vegetation treatment. One cell has neither vegetation nor compost, one cell is planted with vegetation (Panicum virgatum) and no compost, and one cell is planted with vegetation and includes a layer of low-phosphorus compost. Preliminary results have suggested that, after one growing season, the presence of compost and vegetation has no statistically significant effect on nutrient and sediment concentration reduction. The presence of compost does, however, significantly affect above-ground biomass of planted species and the amount of labile phosphorus in the shallow horizon of the of the bioretention soil media.

UVM may be redeveloping part of the Trinity Campus and will evaluate the potential for infiltration opportunities where the existing soils are mapped to be sandy loam, as this is the best area on campus for infiltration projects

UVM complies with the MS4 (Municipal Separate Storm Sewer System) requirements and institutes best management practices (BMP’s) campuswide, such as street sweeping, low salt/brine applications and more. The University complies with stringent federal and state standards for flow restoration and the TMDL for Lake Champlain. The University collaborates with the other MS4s with common watersheds and contributes financially to the Stormwater Utilities in the Cities of Burlington and South Burlington and the Town of Colchester. As part of the MS4 requirements, UVM submits a Stormwater Management Program Plan (SWMP) to the State of Vermont every five years (see attached SWMP) along with Annual Reports (see attached 2022 Annual Report).

UVM regularly meets with the City of Burlington Stormwater Program staff and attends the Chittenden County Regional Planning Commission’s Clean Water Advisory Committee (CWAC) meetings to discuss stormwater projects, regulations, goals, education, outreach, etc. The CWAC also has an MS-4 Subcommittee consisting of representatives of the nine municipalities and three agencies charged with implementing the Rethink Runoff campaign as part of their Public Education, Outreach, Participation and Involvement permit requirements. For many years UVM has also contracted with a stormwater consultant for project permitting, guidance, and to follow the development of stormwater regulations and policies. UVM will continue to follow these avenues to remain educated and informed about stormwater standards, practices, and regulations.

Richards, M. A. (2018). Regreening the Built Environment: Nature, Green Space, and Sustainability. Abingdon: Routledge.

UVM Stormwater Management Program (SWMP)
https://www.uvm.edu/facilities/watersheds-and-storm-water-treatment

Influence of critical bioretention design factors and projected increases in precipitation due to climate change on roadside bioretention performance
A Cording, S Hurley, C Adair - Journal of Environmental Engineering, 2018
https://scholar.google.com/scholar?oi=bibs&cluster=13564587447890781927&btnI=1&hl=en

Phosphorus Removal, Metals Dynamics, and Hydraulics in Stormwater Bioretention Systems Amended with Drinking Water Treatment Residuals
MR Ament, ED Roy, Y Yuan, SE Hurley - Journal of Sustainable Water in the Built Environment, 2022
https://scholar.google.com/scholar?oi=bibs&cluster=17333699770285166689&btnI=1&hl=en

Influence of low-phosphorus compost and vegetation in bioretention for nutrient and sediment control in runoff from a dairy farm production area
P Shrestha, JW Faulkner, J Kokkinos, SE Hurley - Ecological engineering, 2020
https://scholar.google.com/scholar?oi=bibs&cluster=5101439971162376794&btnI=1&hl=en

Evaluation of nitrogen and phosphorus removal from a denitrifying woodchip bioreactor treatment system receiving silage bunker runoff
JC Sarazen, JW Faulkner, SE Hurley - Applied Sciences, 2020
https://scholar.google.com/scholar?oi=bibs&cluster=2231875409008962308&btnI=1&hl=en

Effects of different soil media, vegetation, and hydrologic treatments on nutrient and sediment removal in roadside bioretention systems
P Shrestha, SE Hurley, BC Wemple - Ecological Engineering, 2018
https://scholar.google.com/scholar?oi=bibs&cluster=10649836393185387004&btnI=1&hl=en

Soil media CO2 and N2O fluxes dynamics from sand-based roadside bioretention systems
P Shrestha, SE Hurley, EC Adair - Water, 2018
https://scholar.google.com/scholar?oi=bibs&cluster=5246437948279155284&btnI=1&hl=en

Monitoring methods and designs for evaluating bioretention performance
A Cording, S Hurley, D Whitney - J. Environ. Eng, 2017
https://scholar.google.com/scholar?oi=bibs&cluster=14915175660111101624&btnI=1&hl=en