Geog 2 River Study notes

HideShow resource information
Preview of Geog 2 River Study notes

First 435 words of the document:

Collecting data for river surveys
Speed of the river
We used a hydroprop to measure the speed of the river. We measured the speed of the river in
all 3 locations. At each location we measured the width of the river and dived it by 3. We then
measured the speed of the river in three separate places across the river, one at 1/3 the way
across, the next and the last one 2/3 the way across. This way we could get an accurate reading
because we could find the average of the three different places. To measure the speed using the
hydroprop at the location in the river where we had measured out to we placed the foot of the
prop on the river bed. We made sure the propeller was screwed all the way out but not too tight
that it wouldn't move when we let of it. We made sure we could see the propeller when it got to
the end of the screw we then indicated to the person who has a stopwatch to start timing and we
let go of the screw. We then look to when the prop reaches the end of the screw and tell the
person to stop timing as soon as it does. We the 3 readings we then calculated an average of the
Cross sectional area and wetted perimeter
1. Run a tape across the river along the waterline from bank to bank.
2. Divide the depth by 10 and it should give you 11 points to measure along from bank to
3. Using a ruler measure the depth of the river along the ruler. To measure the depth use a
meter ruler, find the spot on the tape which needs measuring, place the ruler into water
sideways so the narrow edge is facing upstream so it doesn't give an unfair reading by
pushing the water upwards. Do this for all 11 points and jot down the depths in the right
order. When measuring measure whatever is there ­ don't move stones or other
obstructions to measure as these are part of the river bed and need taking into account
when measuring.
4. To make a cross sectional area transfer this information to a graph making sure the same
scale is used for both axis.
River discharge
To calculate river discharge
1. Calculate the speed of flow
2. Calculate the cross sectional area
3. Multiply the two values to give the discharge in cumecs.


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all resources »