In 2017, the Vermont Agency of Natural Resources (ANR) updated the Vermont Stormwater Management Manual (VSMM) to reflect advances in Best Management Practice (BMP) methodologies and design. Bioretention is among the preferred BMPs for stormwater management. Bioretention systems utilize engineered soil media and vegetation to store, infiltrate, and filter pollutants from stormwater runoff. Some members of the stormwater BMP design community are concerned about the ability of this soil specification to promote vegetation growth due to its low organic matter content and water-holding capacity. Commencing in 2023, the State of Vermont has drafted revisions to the 2017 VSMM, this research can inform the forthcoming updates.

In riparian areas of the northeastern United States, well-established reed canary grass (Phalaris arundinacea) stands are common and have proven to be a challenge for the success of tree plantings during riparian forest restoration projects. To address the opportunity for widespread forest restoration and the challenge of reed canary grass (RCG) infestations, the purpose of this experiment was to assess survival of native trees subject to glyphosate, till and mowing management techniques vs. herbicide-free till and mowing management techniques, and to compare RCG density between plots under caried treatments over time. To accomplish this, treatment plots of ten species of native tree stems were planted at eight sites and stem survival was assessed over two growing seasons. In addition, percent cover of RCG was recorded at each site. Chi Square, independent T-test and binary logistic regression statistics were used to assess tree stem survival and the relationship between tree stem survival and percent cover of RCG between treatment and control plots. The data suggest that preparing plots by tilling and the application of herbicide (glyphosate) combined with two mowing events in each of the two growing seasons did not result in higher tree stem survival rates than the treatment plots that were prepared by tilling only and were mowed four times in each of the two growing seasons. As was expected, plots treated with glyphosate, significantly reduced reed canary grass density in the first growing season. However, after the second growing season the percent cover of RCG in the mechanically treated and chemically treated plots was not statistically different. This suggests that the mechanical prescription was as effective at RCG suppression than the chemical, during the second year. Furthermore, the odds ratio produced by the binary logistic regression models in this study can be useful to practitioners and landowners when considering which methods of management to use in restoration projects.

A collaborative approach was used to identify important infrastructural, social, and ecosystem metrics related to dams in the Lake Champlain Basin of NY. The project team formulated a methodology to prioritize dams for removal based on ecological benefit and expected community acceptance. Metrics and priorities were incorporated into an interactive screening tool, available to all partners and community members, that will facilitate the reconnection of fragmented stream networks in the Lake Champlain Basin.

Existing Conditions in Missisquoi Bay
Persistent and relatively severe cyanobacteria blooms that occur in late summer and early fall in
Missisquoi Bay (MB) degrade surface water quality and decrease ecosystem services (Isles et al., 2017a).
Whereas the long-term eutrophication of MB was driven by increased riverine nutrient loads, the build-up
of legacy phosphorus (P) in the sediments, and subsequent release of immediately bioavailable sediment
P to the water column (internal P loading), can drive cyanobacteria bloom initiation, duration, and
severity (e.g., Smith et al., 2011; Pearce et al., 2013; Giles et al., 2016; Isles et al., 2017a).

Due to MB’s particularly high surface area relative to its volume, coupled with its robust inventory of
legacy P in surface sediment, nutrient dynamics in MB are strongly impacted by internal P loading. Much
of the internal P loading to MB occurs during summer months, when the majority of water column P is
likely derived from internal loading, although this relative contribution fluctuates each year due to
variability in weather patterns (Giles et al., 2016; LimnoTech, 2012; Isles et al., 2017a,b). Summer
internal P loading occurs during periods when water residence times in the bay are longest, temperatures
are favorable for cyanobacteria growth, and the water column is stratified, which allows cyanobacteria to
outcompete other phytoplankton for P due to their buoyancy regulation (Huisman et al., 2018).

A stable water column with minimal vertical mixing promotes reducing conditions at the sediment-water
interface (SWI) as dissolved oxygen (DO) in the bottom water is depleted, which leads to release of P
from redox-sensitive mineral phases, primarily iron oxyhydroxides in the case of MB (Schroth et al.,
2015; Giles et al., 2016). Conversely, riverine inputs and wind promote mixing of the water column, input
of riverine sediments, and reoxidation of the SWI, all of which promote accumulation of sediment P
(Giles et al., 2016). Because the system has such a high surface area to volume ratio, MB is particularly
sensitive to wind speed and orientation, completely turning over in response to relatively minor wind
events (e.g., 4 m/s, Isles et al., 2015), facilitating rapid changes in SWI redox chemistry (Smith et al.,
2011). The interannual variability in the duration and severity of cyanobacteria blooms in MB has been
attributed to the frequency and duration of these contradictory conditions at times when water
temperatures are in a range that promote cyanobacteria dominance (Isles et al., 2017a).