Monitoring Study on Bakersfield Dam Removal Comes to an End

BAKERSFIELD, VT – The Franklin County Natural Resources Conservation District, Stone Environmental, and others, have completed a four-year monitoring study in Bakersfield at the former location of the Johnsons Mill Dam along the Bogue Branch.  This study, funded by the United States Environmental Protection Agency under assistance agreement (LC 00A00707-0) to NEIWPCC in partnership with the Lake Champlain Basin Program (LCBP), included annual monitoring of various physical and biological metrics to improve understanding of dam removal impacts on aquatic habitat to inform future river restoration designs.  

The Johnsons Mill Dam, which was once used for a lumber mill, was originally constructed in the early 1800s, but since abandonment, had acted as a barrier to the natural passage of aquatic organisms and helped to increase the temperatures in the stream, making the habitat unsuitable under certain scenarios for cold water species like brook trout. The dam was removed in 2021 following a partial breach during the Halloween 2019 storm during which parts of the dam broke and the water level dropped seven feet and thousands of cubic yards of sediment that had built up behind the dam over decades went downstream uncontrolled. In 2021, an engineered removal plan was implemented by Jeff Corey Excavating to remove the remaining dam structure and some additional sediment upstream; performing removal of old, derelict dams in a controlled manner reduces risk of sudden failure and potential downstream infrastructure damage.  

The dam removal, completed in August 2021, involved minimal upstream sediment removal, with the intent for natural sediment movement through the system over time. This four-year monitoring effort focused on tracking channel evolution and sediment transport processes, including streambed material characterization through pebble counts and surficial armor layer analysis, as well as high-resolution topographic and bathymetric surveying utilizing LiDAR data collected via unmanned aerial vehicle and helicopter. Overall, this project and on-going work at the Johnsons Mill Dam site provides insight into how sediment moves through riverine systems, how streambanks and floodplains re-establish, and how the system re-naturalizes, ultimately seeking geomorphic equilibrium, following dam removal.

This study found that 21,107± 6,800 cubic yards of material left the 84-acre area of interest that had topobathymetric data collected over it in the time period between two and four years post dam removal; this area extended beyond the extents of the dam removal project footprint and the impoundment. Much of the sediment was lost between the 2023 and 2024 flights, during which two high-magnitude flood events, The Great Vermont Flood of July 2023 (July 2023 Flood) and December 2023 Flood, occurred. The channel has worked to establish point bars, vegetated areas, and new paths as it freely interacts with the banks and river corridor it sits within. As it moves, there are some concerns about risk to infrastructure, which are being examined by a team of engineers to determine next steps and work with the river to find acceptable interventions to achieve the original goals of the dam removal, as well as protect infrastructure.  

Insights related to which metrics and data collection methods were best suited to help answer key questions about the site dynamics, frequency of monitoring efforts, utility of pre- and post-removal monitoring data sets, and potential conflicts with neighboring infrastructure were explored in this study. Information gleaned throughout this study have informed monitoring and data collection efforts at other dam removals throughout Vermont; nine dams were removed in Vermont in 2025, some of which included monitoring efforts similar to this project. Continuing to learn from this site and others will improve future dam removal and stream restoration designs across Vermont.  

All reports related to this study and information on the original dam removal can be found here: https://www.franklincountynrcd.org/jmdremoval  

This project has been funded by the United States Environmental Protection Agency under assistance agreement (LC 00A00707-0) to NEIWPCC in partnership with the Lake Champlain Basin Program (LCBP). NEIWPCC manages LCBP’s personnel, contract, grant, and budget tasks and provides input on the program’s activities through a partnership with LCBP. The contents of this document do not necessarily reflect the views and policies of NEIWPCC, the LCBP, or the EPA, nor does NEIWPCC, the LCBP or the EPA endorse trade names or recommend the use of commercial products mentioned in this document. 

Although the information in this document may have been funded wholly or in part by the United States Environmental Protection Agency (under agreement [LC 00A00707-0]), it has not undergone the Agency’s publications review process and therefore, may not necessarily reflect the views of the Agency and no official endorsement should be inferred. 

About Franklin County Natural Resources Conservation District 

The Franklin County Natural Resources Conservation District empowers and partners with land stewards and communities on the ground by supporting connections that benefit natural resources, water quality, soil health, and the working landscape in Franklin County and across Northwest Vermont. To learn more, visit www.franklincountynrcd.org or call 802.582.3133. 

Figure comparing channel thalweg delineated from the as-built survey (2021), topographic LiDAR (2022), and topobathymetric LiDAR data collected in Year 2 (2023), Year 3 (2024), and Year 4 (2025).

Map depicting areas of potential erosion (blue) and deposition (red) between Year 2 (2023) and Year 4 (2025) along the entire Bogue Branch reach within the project AOI.