There may still be snow on the ground but the Lewis Creek Association has begun its call for volunteers for its summer fieldwork. Planned for this summer is monitoring water quality in various local creeks, and managing the invasive plant European frogbit.
Lewis Creek Association Program Coordinator Krista Hoffsis noted that monitoring water quality allows LCA to observe trends and take note of changes in water quality when they turn up.
“This year, we will be doing a ‘focus study’ in Thorp Brook and Kimball Brook to try to zone in on potential sources of pollution,” said Hoffsis, “so that we can install green infrastructure practices to address those pollution sources.” Another aspect of this summer’s work will be examining how well existing efforts are working.
“For water quality monitoring, our focus studies on Thorp Brook and Kimball Brook will reveal the effectiveness of green infrastructure practices that were installed or will be installed this year,” said Hoffsis. “(South Chittenden River Watch, a volunteer group tasked with water monitoring) will ‘bracket’ practices by testing the water quality both upstream and downstream of the green infrastructure practice. SCRW will test for phosphorus and turbidity, among other parameters.”
Phosphorus is a concern because in excessive amounts, it can lead to algae blooms in Lake Champlain. These blooms can create low-oxygen conditions in the lake, which kills fish. Water turbidity, too, can affect aquatic life in a stream. “Turbidity,” explained Hoffsis, “is a measure of the ‘muckiness’ of the water, or how much ‘stuff’ is in it.” Contributors to water turbidity include algae and sediments in the water column. Rainwater runoff increases turbidity. Monitoring these factors and others will allow LCA to know what effect their work is having.
Also planned is a rain garden for Shelburne Community School. This bioretention area will capture and retain excess rainwater, allowing for filtering before the water reaches McCabe Brook and Shelburne Bay, Hoffsis noted.
Water quality monitoring informs both LCA and town decision-making, including the towns of Shelburne, Charlotte, and Hinesburg. Water quality monitoring also has effects beyond individual towns, Hoffsis said.
“This work has impacts on the LaPlatte and Lewis Creek watershed level, which therefore impacts the entire Lake Champlain watershed and gets us closer to a healthy and thriving Lake Champlain,” she said. State efforts, too, may be informed by monitoring data collected by LCA; funding and legislative decisions may benefit from this on-the-ground information about what’s happening in local ecosystems and watersheds. Landowners, too, might be able to use LCA-collected data in handling stormwater issues or creating habitat if possible.
Another project will involve removing frogbit. Frogbit was first found in Town Farm Bay and the lower LaPlatte in 2007 and 2008. The invasive plant can cover the water surface, effectively preventing native plants from accessing needed resources including light and nutrients. Control efforts will focus on Shelburne and Town Point Bays, where the plant will be hand-pulled, allowing native plants and animals to maintain their habitats. These efforts, which have been ongoing each summer since 2009, have already reduced the invasive plant’s cover from 50% to less than 6%.
LCA water monitoring runs from April to November, though it must occur during periods of high flow and therefore is weather-dependent. Frogbit removal occurs during the summer only, from mid-June through mid-August.
SCA relies on volunteers to assist in collecting data and removing frogbit. The group handling water quality will sample streams six times over the course of the field season, working from 10 to 20 hours total including training, fieldwork, and meetings. Frogbit-focused volunteers might expect to spend a couple of half-days over the summer in a canoe, pulling out the invasive plants.
Other volunteer opportunities exist in community outreach and education. Interested people can visit www.lewiscreek.org, find and fill out the “Become a Friend of Lewis Creek” form.