February 2016: Through the persistence of a group of conservation partners including Vermont DEC, Poultney Mettowee Natural Resources Conservation District (PMNRCD), South Mountain Research and Consulting (SMRC), and residents of Pawlet, five significant gullies have been identified on Flower Brook. A stormwater master planning grant awarded to PMNRCD through the VDEC Ecosystem Restoration Program (ERP), and a limited field assessment was completed in May, 2015, to identify and characterize erosional gullies draining to a 2.2-mile reach (M05T03.04) of Flower Brook.
The five gullies identified ranged from 340 feet to over 1200 feet in length, and originate at edge-of-field settings where concentrated snowmelt and runoff in perennial or ephemeral channels have been directed to steeper, forested side slopes of the Flower Brook floodplain. These channel segments have cut down into erodible glacial sediments and become overwidened. Sediment produced from these gullies has entered the Flower Brook, particularly during extreme events, such as the floods of December 2000, January 2006, and August 2011. Other factors which may have contributed to formation of these gullies include: (1) increased imperviousness in the upstream catchment areas associated with residential development and logging activity; and (2) enhanced connectivity of surface runoff from logging access networks and road and driveway networks in the upstream catchments.
Various restoration and conservation projects have been identified to address sediment production from these gullies, and willing landowners are working with the District and other partners to design a gully management plan that will address not only the local concerns of stream instability and loss of agricultural land, but also the overall health and stability of Flower Brook and the protection of Pawlet from future sediment and floodwater inundation.
This blog is made possible with a grant through Lake Champlain Basin Program.