River Study - Education Scotland

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River study
Introduction
• Rivers usually follow three stages: the upper, middle
and lower courses.
• Each stage has its typical features.
• The upper course usually is steeper, with fastflowing water and features of erosion.
• This assignment aims to see if the upper course of
the Boghall Burn follows this pattern.
Location
• The river I have
chosen to study is
the Boghall Burn.
• It is located in the
Pentland Hills
between
Caerketton Hill and
Woodhouselee Hill.
River study
Does the Boghall Burn follow the typical pattern
of a river in its upper course?
Sample points
• I selected four points
along the burn which
were easy to get to.
• I took measurements
at each of these
points.
Point 4
Point 3
Point 2
Point 1
Sources of information
1. Measuring the river
(a) Width – used a tape
measure
(b) Depth – used a metre
stick
1. Measuring the river
(c) Speed – used a flow
meter
(d) Gradient – used a
clinometer
1. Measuring the river
(e) Size of stones – used a dial caliper
2. Fieldsketching and photographs
Findings
Point 1
Point 2
Point 3
Point 4
Gradient 5°
10°
10°
15°
Width
1.1 m
2.2 m
0.5 m
2m
Depth
6/10/12 cm 5/11/4 cm
LB/M/RB
20/25/20 cm 6/10/7 cm
Speed
0.14/0.35/
LB/M/RB 0.2 m/s
0.15/0.9/
0.4 m/s
0.08/0.2/
0.02 m/s
0.3/0.6/
0.35 m/s
Size of
stones
6 × 4 cm
15 × 10 cm
18 × 9 cm
11 × 7 cm
(LB = left bank, M = middle, RB = right bank)
Point 2
Faster flow at a small
rapid.
Point 3
Slower flow at a small
pool.
• Most of the rocks were smooth and
rounded by the water.
• Larger rocks were found further
upstream.
• The gradient increased further upstream.
• The middle of the river tended to be deeper and
have the faster flowing water.
• The depth and speed did not follow a pattern
downstream.
• Point 2 had the fastest flow of water at a small
rapid.
• Point 3 was a deeper pool on a flatter ledge
where the water was much slower.
• Rocks varied in size – smaller rocks were found
near the rapid.
Speed of the river
This graph shows
that the middle of
the river has the
fastest flow but
there is no link
between speed and
distance upstream.
Point 1
Even in a small section of this
river differences can be seen
in the speed and width.
Point 2
Conclusion
The Boghall Burn shows many characteristics of a
river in its upper course:
• narrow
• follows a fairly straight course
• no real meanders
• some rapids
• large boulders.
These characteristics do not necessarily follow a
regular pattern downstream as different rock types
affect the course of the river.
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