# Rivers Velocity

Topics: Geomorphology, Sediment, Area Pages: 8 (2733 words) Published: December 15, 2012
In my task question I am going to study why does the velocity vary downstream? To carry out this investigation we will be going to Carding Mill valley; carding mill valley is located near the border of Wales, North West England in Shropshire. (This can be seen on image 1) (Image 1)

(Image 1)
This means we are collecting primary data which is mainly so we can get accurate and reliable set of results. In order to answer the task question I have devised the following sub-hypothesis * Hypotheses: “The velocity and dischage

* Increase downstream”.
* “Does the river become more efficient downstream and what are the effects on bed load. ” * “The gradient decreases downstream”
* The roundness and bed load increase downstream and as the river gets faster it carries greater amounts of bed-load” In my conclusion I will be linking all of these hypotheses to velocity of the river.

Carding Mill valley (long Mynd):
The name Long Mynd means "Long Mountain”, it is a rural area and it is one of twelve valleys the landscape is very hilly and steep and because of this there are not many buildings. (This can be seen on the contour lines). The soil is stony, shallow, acidic and high in lime therefore giving a giving a low level of fertility. The sole agricultural use of the Long Mynd is sheep farming; the open hill is common grazing land, this helps to keep the level of rough grass and shrubs low.

Site 1:Lower River.
Site 2: Midpoint of the River.
Site 3: Upper River
Methodology
| Sites| Equipment| MeasureMents.| How Many?/How of often?| EvaluationsTechniques. | Velocity| 1-3| * Ranging poles, * Stopwatch, * Tape measure| Seconds| 5 times| To see how velocity changed with distance downstream.| River Gradient| 1-3| * Clinometer * Ranging poles| Degrees| Once| To see a difference in the Gradient.| Bed load size| 1-3| * Ruler.| Centimetres| 10 times| To see if the size of the rocks in the bed load if the height of the rocks were similar. | Bed load roughness| 1-3| _____| 1-6 on the callieux scale.| 10 times| To see if the roughness of the rocks were similar in that area of the river.| Wettedperimeter| 1-3| •Chain * Tape measure| centimetre| once| To find of how the wetted perimeter affected the velocity of the river| width| 1-3| * Tape measure| centimetre| once| To see if the width of the river was similar to the other sides width.| depth| 1-3| * Tape measure| centimetre| once| To see if the width of the river was similar to the other sides depth.|

Gradient: to measure the gradient first the two ranging poles need to be spread out between a distances of 10 meters on an incline or decline, then the clinometer is used to measure the angle between two poles.(you look through a eye with one eye to see the angle measuring scale and a horizontal line. With the other eye, you sight on the object you want to measure). Evaluation: sometimes the pole heights were different this gave an incorrect angle.

Float Velocity: for this we measured 10 meters using the tape measure and the marked the distances using two ranging poles, we put a crock in the river upstream of the 1st pole. The stopwatch was started when it passed the 1st pole and was stopped when it got to the 2nd pole.(To get accurate results we repeated this 5 times) Evaluation: The cork kept on getting stuck because of shallow of water and the rocks. Bed load (size/roughness): We first collected 10 different bed load samples and then measured the long axis in centimetres and then we compared the roughness them on a scale of 1-6 on the cailleux scale. (1 being rough and 6 being smooth) Evaluation: the roughness may not accurate be accurate as it was based on our opinions and length was...