Assessment of Fluvial Geomorphology in Relation to Erosion and Landslides in the Mad River Watershed in Central Vermont June 3, 2003 FINAL DRAFT Prepared For: Prepared By: Step by Step, Lori Barg 113 Bartlett Rd. Vermont Geological Survey Plainfield, Vermont. 05667 103 South Main St., Laundry Building phone: 454-1874 fax: 454-0145 Waterbury, VT 05671-0301 e-mail: [email protected] Mike Blazewicz Friends of the Mad River Waitsfield, Vermont 802-496-9127 [email protected] Research supported by the Vermont Geological Survey, Dept. of Environmental Conservation and the U.S. Geological Survey, National Cooperative Mapping Program, under assistance Award No. 02HQAGOO49. The views and conclusions contained in this document are those of the author and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government or the State of Vermont. i Acknowledgments We’d like to thank the volunteers with the Friends of the Mad River who walked miles of stream, endured training in the rain, wet feet and did a terrific job assessing the physical characteristics of their streams. The knowledge that the volunteers brought was invaluable to this study - living along a stream for a long period of time gives one a great perspective on how rivers change. Volunteers included Mike Hoffman Kari Dolan, Ned Kelley, Ken Felderman, Elizabeth Walker ,Bridget Butler, Jim Siriano, Susan Ensalada, Wendy Cox, Shannon Hill, Steve Putlik, Patti Greene-Swift, Richard and Ginger Hiscock, Clark Amadon, Phil Huffman, Kathy Krier, Deb Kirchwey, Ryland and Jill Swenderman, Liz Tabor, John Summers, Dorothy Tod, and Ann Day. Town personnel from Moretown, Waitsfield and Warren especially Wayne Kathan, Mike Ricker and Craig Elwell who took Lori on a watershed tour to see areas where flood damage have occurred, and offered their perspective on reasons for damage, and types of damage. Earline Marsh and John Malter provided invaluable aid in acquiring historical information and photos. Kathy Donna and Dan MacKinley of the Green Mountain National Forest. Mary Nealon of Pioneer Environmental, Jason Lisai of Sugarbush, Mike Mayo of Mountain Water System, and Ellen Sivret of the Natural Resource Conservation Service provided background data. Lyle Steffen of the Natural Resource Conservation Service performed the flood frequency analysis. Fred Spencer, weather observer for Waitsfield graciously provided 48 hour precipitation totals during significant floods. Staff of the Vermont Agency of Natural Resources River Management Division including Shannon Hill, Mike Kline and Shayne Jaquith who worked on the Phase !, II and III protocols. This job couldn’t have been done without them. Sandy Reider Bill Warnock and Marcus Pante who paddled the lower part of the river and helped look for mass failures, bedrock control and other stream features that made the paddling interesting. Thanks to George Springston who overlaid the orthophotos over time, Rick Dunn, and Fiona Johnstone of Norwich University and Nathan Donahue for mapping bedrock and stream features while they were mapping surficial geology. And last, but not least, special thanks to Larry Becker of the Vermont Geological Survey for the support of this project. “Water is H20, hydrogen two parts, oxygen one part, but there is a third thing that makes it water and nobody knows what that is” –D.H. Lawrence Thanks to Earline Marsh, historian, writer, poet, for the following: "One wonders where Mad River got its name. William Strong, the surveyor of the town, called it by its present name in his field notes of 1788, and one guesses that his party gave the name because of some unhappy experience with its uncertain habits." Matt Bushnell Jones, 1909, History of Waitsfield, 1782-1908 "Mad River received its name doubtless from the fact that -- the mountains being so near and steep -- the surplus water is almost immediately thrown off into the brooks, and by them poured out into the river, which of course rises like sudden anger overflowing its banks and devouring them at will." Vermont Gazetteer, Abby Maria Hemenway, 1882 ii TABLE OF CONTENTS Abstract .......................................................................................................................................................................1 Introduction ...............................................................................................................................................................2 Section 1.0 Background Data ..................................................................................................................................3 1.1 Description Of the Mad River Watershed .........................................................................................3 1.2 Bedrock .....................................................................................................................................5 1.3 Surficial Geology ......................................................................................................................5 1.4 Soils...........................................................................................................................................6 1.5 Geomorphology.........................................................................................................................6 1.6 Hydrology..................................................................................................................................7 1.7 Small Stream Hydrology .........................................................................................................11 1.8 Orographic Influence and Storm Tracks ..................................................................................11 1.9 Human Influence ......................................................................................................................12 1.10 Road Impacts..........................................................................................................................13 1.11 Landslide History ...................................................................................................................13 1.12 Flood Damage History ...........................................................................................................13 1.13 Cost of Flood Damage............................................................................................................15 Section 2.0 Methodology ...........................................................................................................................18 2.1 Data Review .............................................................................................................................18 Section 3.0 Summary of Previous Studies ..................................................................................................19 3.1 ANR Cross-Sectional Study.....................................................................................................19 3.2 Stream Sedimentation..............................................................................................................19 3.2.1 Brook Trout Study....................................................................................................20 3.2.2 Effects of Logging Practices ....................................................................................20 3.3 Salamander Study.....................................................................................................................20 3.4 Summary of Existing Data: Bridges.........................................................................................21 Section 4.0 Volunteer Involvement.............................................................................................................25 Section 5.0 Methodology: Field Assessment .............................................................................................26 5.1 Data Presentation......................................................................................................................27 5.2 Pebble Counts...........................................................................................................................28 Section 6.0 Summary Of Results: ..............................................................................................................29 6.1 Results of Quantitative Geomorphic Assessments..................................................................29 6.1.1 Hydraulic Geometry ..............................................................................................................29 6.1.2 Channel Evolution Model / Stream Type..............................................................................34 Section 6.2 Results of Quantitative Geomorphic Assessments...................................................................35 6.2 Quantifying Horizontal And Vertical Change..........................................................................35 6.2.1 Lateral Migration - Channel Migration Zone........................................................................35 6.2.2 Vertical Degradation and Grade Control..............................................................................36 6.3 Pebble Counts...........................................................................................................................39 6.4 Channel Constriction with Infrastructure .................................................................................39 Section 7.0