5.13. (9/25) Plot and Interpret W-Q Data

Question 1

How was the layer of gravel in Saucon Creek supported?

Answer 1

class supported

Question 2

what happened when the gravel pebbles of Saucon Creek were moved?

Answer 2

There was a mix of sand and gravel underneath (sometimes matrix supported by sand)

Question 3

what is d50 armored?

Answer 3

gravel pavement/armor
- gravel is lining the channel

Question 4

what is suspended load?

Answer 4

as long as water is flowing; mud stays in suspension; flowing water can essentially “float” objects
*mud and silt

Question 5

What is the bedload?

Answer 5

The leftover heavy stuff
*sand and gravel

Question 6

why can we find mud in floodplains? what form do they take on?

Answer 6

• water stops flowing when water comes out of the channel causing settlement
• vertical structure
  *behaves like a lake

Question 7

What form do bedloads take on? how are they built?

Answer 7

• laterally
• sediment is shaped by the horizontal movement of water

Question 8

how are things settled in the floodplain versus bedload?

Answer 8

vertically vs horizontally

Question 9

How do levees form? what has nature designed them to do?

Answer 9

• velocity goes to zero when water spills over to bankfull and sediment falls out right next to the channel causing the beginning of a floodplain to be higher
• hold water during big rainstorms

Question 10

why do people build levees?

Answer 10

to prevent houses on floodplain from flooding
- to keep channel from flooding onto floodplain

Question 11

how do we measure bankfull depth?

Answer 11

hbf: tape to water + water to bottom

Question 12

What is s?

Answer 12

slope

Question 13

What is U?

Answer 13

velocity

Question 14

What is the equation to find discharge?

Answer 14

Q=UA
*conservation of mass

Question 15

what is A? What is its equation?

Answer 15

• cross-sectional area
• w*h

Question 16

what is the wetted perimeter of the channel? (equation)

Answer 16

P=2h+W

Question 17

what is hydraulic radius? (equation)

Answer 17

R=A/P

Question 18

What is the R for a shallow channel?

Answer 18

approximately the depth h

Question 19

how do we know a flow is steady?

Answer 19

no change in velocity with respect to time (no ΔU/τ)

Question 20

how do we know a flow is uniform?

Answer 20

no change in velocity with respect to position (no ΔU/x)

Question 21

What is the point of Homework 3?

Answer 21

understand the relationship between sediment organization, the width of the channel, and the amount of water being carried
Q- independent x
w- dependent y (responding)
*use a power law because

Question 22

why would we plot a log-log graph? what is the equation of the line?

Answer 22

turns a curve into a straight line
w = yint*x^m