1. Abstract This project identifies, maps, and interprets the various sediment packages that resulted from the construction of E. N. Colton’s saw and shingle mills on Mill Brook in West Bolton, Vermont. A timber crib dam was constructed on the Brook between 1849 and 1852, and remained until sometime between 1905 and 1914. The UTM coordinates of 29 survey points were used to map the relative locations and lateral extents of five major sedimentary features, including the wedge of silt which filled the millpond. Various sedimentary features were identified with a bucket auger in 10 locations and in 5 soil pits, and include glacial till and clays, landslides, alluvial terraces, pond sediments, alluvial fans, and roadworks. Erosion and slope failure increased as forests were harvested for timber. The sediment flux of the stream dramatically increased, filling the millpond with silt. We calculated the former millpond to contain 11,321.48 m 3 of silt. We used historic land use records to estimate the life span of the dam at a maximum of 65 years. We compared samples of historic pond sediment and modern stream alluvium to calculate a percent compaction value for the pond sediment wedge. We then used uncompressed volumes of sediment accumulated over known time intervals, both modern and historic, to calculate a modern sediment flux of 0.14 m 3 /yr and a historic flux of 524.9 m 3 /yr. When the dam breached, after the collapse of the lumber industry and abandonment of the mills, the stream incised through the pond sediments and reverted to a high- energy erosional environment. Our field work and observations suggest that Mill Brook has occupied five different channels during the past 100 years. Topography, woody debris dams, landslides, and periodic flooding events have heavily influenced channel location: especially in 1990 when a large flood altered Mill Brook to its current streambed. Our data and field observations show that the landscape responded directly to historic human land use activities, the most egregious of which was clearcutting. The great difference in sedimentation rates shows that hillslopes have been stabilized by the re-growth of forests, and that very little sediment is currently available for transport by the stream. We can infer that the landscape is capable of adjusting to anthropogenic impacts through rapid geomorphic change. Anthropogenic Impact and Geomorphic Recovery on Upper Mill Brook, West Bolton, VT Schematic interpretation of geomorphic response to human-induced landscape change E.N. Colton shingle mill, at survey point O, c. 2005 Soil pit U: soil horizons developed from pond sediment, stream gravel, and landslide debris Timber crib dam, at survey point A, c. 2005 View upstream (east) from ATV trail at point Q, showing 4m gorge carved on July 4th, 1990. Old IP road grade shown with dotted lines. Large rotational failure at ‘A’. Pallet bridge in foreground. Large rotational failure at point R due to groundwater piping through unconsolidated glaciolacustrine sediments. Located south side of present stream channel. Sawn stumps are present in a relic soil horizon beneath the slide. Upper Mill Brook Valley seen from West Bolton Cemetery, adjacent to site of Baptist Church. A panoramic photograph of the area, taken c. 1900 from the church steps, documents deforestation. It is now in the possession of the VT Army National Guard and is classified information. Land use history from comparison of historic and modern property maps; stratigraphy and channel migration from field analysis of sediments. Church Cemetery The stratigraphy of the area preserves a record of the responses of the Mill Brook area to anthropogenic influences throughout history. Diagrams are NOT to scale…they show relative sizes and positions of features, which have been simplified and stylized. All are map views looking east, upstream. Corey Coutu Robert Zimmermann UVM Geology, 2005