may 2006 suncook river avulsion epsom, new hampshire · legend # erosional feature # high water...
TRANSCRIPT
Epsom Traffic Circle
Old Mill
0.75
Mile
New Channel
Scoured AreaAbandoned Channel
May 2006 Suncook River AvulsionEpsom, New Hampshire
Digital Mapping by the New Hampshire Geological Survey, NHDES
®
Data Sources1. DOT Roads Coverage; New Hampshire Water Bodies Coverage2. DOT Arieal Photography3. Surficial Geologic Map of the Gossville Quadrangle, R. Goldsmith, New Hampshire Geological Survey Open-File Map; USGS 24K Digital Raster Graphic4. USGS Digital Raster Graphics and Elevation Models
Chad Wittkop, phone (603) 271-3915, e-mail: [email protected] Bennett, phone (603) 271-4087, e-mail: [email protected] Chormann, phone (603) 271-1975, e-mail: [email protected] R. Wunsch, State Geologist, phone (603) 271-6482, e-mail: [email protected]
Suncook River
Bear Island
1. Location
Glacial Lake and Stream Sediments (Sand, Gravel, and Silt)
0.5
Miles
3. Surficial Geology
Legend
Glacial Till
Shallow BedrockFloodplain and Stream Terrace
Wetlands
1
Mile
4. Topographic Map and Elevation Model of Avulsion Area1967 Topographic Map Digital Elevation Model
Saddle Between Sand RidgesElevation 342 ft
High Water MarkApproximate Elevation 335 ft
River Elevation 324 ft
River Elevation300 ft
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Legend# Erosional Feature# High Water Mark# New Channel# Sand Sheet# Undisturbed Road
2. Differential GPS Surveys May 22 and 24, 2006
0.5
Mile
Epsom Well House
New Channel, Abaonded Channel, and Erosional Features
Old Mill
Gravel Pit
0 0.2 0.4 0.6 0.80.1
Miles
LegendNew Channel
Scoured AreaAbandoned Channel
Length of New Channel: 0.44 miles (2,323 ft)Length of New Channel Plus Pre-existing Channel: 1.03 miles (5,483 ft)Length of Abandoned Channel (West): 1.52 miles (8,026 ft)Length of Abandoned Channel (East): 0.45 miles (2,376 ft)Total Length of Abandoned Channels: 1.97 miles (10,402 ft)Gradient of Abandoned Channel: 16 feet/mileGradient of New Channel: 23 feet/mile
Channel Statistics