Riparian Vegetation and Geology in the
Jail Branch Watershed in Central Vermont
Tristan Hansell and Keith Pelletier
Research Objective
Abstract
The Jail Branch River in Central Vermont is classified by the EPA as an impaired stream. This
poster lists sources of the streams impairment and displays images that can be used to assess the
change in riparian vegetation along the stream channel. These images show that riparian
vegetation has returned to two areas along the Jail Branch. We conclude that the riparian
vegetation is instrumental in the reduction of some of the pollutants that impair the stream.
Study Area
Through the use of historical images and current photos of the Jail Branch river
this poster will recommend mitigation strategies for this impaired stream.
Past and Present Images
1927 Flood
This historic image is from the
flood of 1927 in East Barre, VT.
The water is moving rapidly
because of the large rocks and
woody debris present throughout
the channel. There is a steep
cliff on the right side of the
stream with barely any
vegetation. The left side has
some trees but is mainly just
large rocks.
23 km Stream
124.58 km2 Watershed
Public Drinking Supply
Pollutants:
Urban Runoff
Sedimentation
Channelization
Nutrients
Heavy Metals
Data Source:
http://oaspub.epa.gov/pls/tmdl/
enviro_v2.wcontrol?p_id305b=VT08-15
Tristan Hansell
Keith Pelletier
Geology 151
December 07, 2005
This image is at the same location but
taken today. The immense amount of
vegetation that has grown in along this
river channel is a good example of a
successful riparian zone. This zone will
help to stabilize this hill slope and
hopefully lead to a decrease in future
flooding, along with many other benefits
that come with riparian vegetation.
1936 Flood
Photo of Jail Branch at bankfull flow
in Spring of 2005 (Photo: Stefan Hard)
Geology
History
Soil Profile Glacial
Study area is near the eastern terminus
4.6 m
GPS Coordinates of Soil Pits:
0704451E 4893273N
of Lake Winooski and would have been
under the Laurentide Ice Sheet. The
soil profile could be an example of
glacial deposits due to the lack of
sorting and various sized subangular
clasts. The presence of eractics in the
study area also indicate glacial
deposition of sediments. (Wright and
Larsen, 2004).
Channel Morphology
Cross Section of Stream
The historic photo was taken during March of the 1936 flood. There
is one low river terrace which we believe the river is occupying in the
picture. You can see some trees poking out of the river that have
become engulfed by this river during this flood event. There is a
second river terrace that the houses in the foreground are sitting on,
and even a possible third terrace on the far side of the river which
has a lighter tone and is just above the tree line.
Riparian Vegetation
Uncertainties
Benefits:
The use of these images to assess riparian vegetation is limited by the
extent of the photos. Further analysis might use aerial photos with
geographic information systems and remote sensing techniques to
examine the change and health of the riparian vegetation.
Adds Large Woody Debris
Bank Stability
Shade
Habitat
Reducing runoff and sedimentation
(Booth 1991)
Conclusion
Image Source: http://www.agr.gc.ca/pfra/land/stream/1d13.gif
Mixed bed with Pool and Riffle Topography
Manning’s n=.063
Velocity 1.15m/s
Area 4.13 m2
Discharge 4.74 m3/s
0
-10
-20
-30
-40
-50
-60
Series1
-70
Width (m)
S1
Depth (cm)
Image source: http://www.fisheries.nsw.gov.au/__data/assets/image/5761/df92-fig1.gif
GPS Coordinates of cross section:
0703654E 4893224N
Photo of cross section area of stream
This is more recent view of the same
area we can see during the 1936
flood. The amount of vegetation has
changed tremendously on the hill
slopes and even on the riparian
zone, as we are not even able to
see the river in this photo.
Our observations and measurements along the Jail Branch indicate
that the landscape surrounding the river has changed significantly.
Our soil pit reveals deposits that are characteristic of glaciation
approximately 15,000 y.b.p. The EPA has documented human
alterations to channel morphology and other sources of pollution in
the stream. The comparison of images from the 1927 and 1936
flood events to current images taken in the same location suggest
that riparian vegetation has regrown along the Jail Branch River.
The growth and preservation of riparian vegetation along the
channel is the beginning of a mitigation plan to reduce the amount
of physical and chemical pollutants in the stream.