Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Hydro. Exam 1 Concepts > EX1 > Flashcards

EX1 Flashcards

(66 cards)

Start Studying
1
Q

How to Manually Delineate a Watershed

A
  1. Get map-Overlay the map
  2. Locate outlet on map
  3. Identify existing drainage network
    4.Identify high ground
    5.Starting at the outlet, visualize flow paths
  4. Perform water drop test
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Delta Storage Equation

A

deltaS=P-(G+F+E+R+T)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

1 Acre Conversion

A

43560 ft^2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Types of Rainfall

A

Cyclonic
Orographic
Convective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cyclonic

A

Long storm durations
Cold or warm fronts
Cold fronts often form tornadoes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Orographic

A

Intense storms
westerly sloped mountains
Common in Denver, SW monsoonal moisture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Convective

A

Heavy thunderstorms
heavy rain from slow moving storms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Rainfall Measurement

A

Physical measurement on ground (Gages)
Radar Rainfall
Gauge Adjusted Rainfall (GARR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Tipping Bucket Rain Gauge

A

Measures time and depth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Approaches to interpolate rainfall

A

Areal Average
Thiessen Polygon
Isohyetal
Doppler Radar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Arithmetic Mean

A

gauges in watershed
simple
least accurate
ok with uniformly spread gages
p=1/n summation Pi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Thiessen Polygon

A

Gages in or near watershed
a weight technique
most widely used

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Isohyetal

A

contours of consistent precipitation
need extensive gage network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Doppler Radar

A

Most accurate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Thiessen Polygon Method

A
  1. Connect each rain gage use dashed lines
  2. Create a bisect line to each dashed line
  3. Extent bisect lines to the watershed
  4. Connect bisect lines

p=1/A summation Ai*Pi
A=summation Ai

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Importance of Streamflow

A

Municipal water supply
Water rights allocation
Reservoir operations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

John Wesley Powell

A

Expedition to survey the west
Professor in Illinois
Went down Grand Canyon/Lake Powell
Flow measurement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Streamflow

A

Discharge, Q
Rate at which volume of water passes through cross section of area
Q=VA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Streamflow Devices/Methods

A

Gaging rod
Dye tracer test
Float method
ADCP (Acoustic Doppler Current Profiler)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

USGS Method

A

Subsection widths
Q=summation Vidiwi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Stream gage technologies

A

Stilling Well
Pressure transducer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Rating Curve

A

Represents sate vs discharge ( gage H vs Q)
Convert water level readings into flow rate
Create it
Use it
Adjust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Evaporation

A

water transformed to vapor from liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Evaporation affected by

A

soil type, soil moisture content, temp …..

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Transpiration
Water moves through plants and evaporates through leaves
26
Transpiration affected by
Type of vegetation, Growth stage
27
Pan evaporation
pan designed to measure evaporation by monitoring loss of water over time
28
Why probability and frequency analysis?
1. Hydrologic processes are random 2. Use stats to interpret and predict
29
Random variables
Discrete Continuous
30
Discrete RV
A countable # of distinct values # of children in family # of students in classroom
31
Continuous RV
An infinite # of possible values height, weight .....
32
Return Period
The average time between events p=1/T
33
Reliability
The probability that a T-year storm event will not occure in n years R=(1-P)^n
34
Risk
Probability that a T-year storm will occur at least once in n years Risk=1-R
35
Binomial Distribution
Probability of n successes in N trails independent from each other
36
Infiltration
Water that goes into the ground
37
Interception
Water that does not hit the ground (hits trees)
38
Infiltration Capacity
Max infiltration rate
39
Green-Ampt Model
Best for soil that exhibit a sharp wetting front Darcy's Law (Ifiltarion is proportional to gradient)
40
Horton's Method
Used to describe potential infiltration rate vs time Decay graph
41
Phi index method
1. Calc volume of direct runoff 2. Assume # of intervals 3. Sum of rainfall in each interval 4. Calc phi 5. check phi vs excess precipitation 6. Iterate if necessary 7. Check Pe=rd
42
Model Phi Index
An index only Intensity can be taken uniformly Non-linearly depending on index
43
Model Hortons
Empirical Nonlinear Represented by a first order math equation
44
Model Green-Ampt
Analytical basis on soil properties Nonlinear Wetting front travels through soil Account for unsteady rainfall
45
Hydrologic Design
Assessing impact of hyrdologic events Determining values for key variables Design system to perform adequately
46
Hydrologic Design process
1. Select runoff 2. Predict runoff 3. Route flow 4. Evaluate flow at points of interest 5. Design system 6. Iterate | r
47
Estimated limiting value
largest possible for a hydrologic event at given location (based on the best hydro info)
48
Probable Max Precipitation (PMP)
estimated greatest depth of precipitation for a given duration that is physically possible and depth of rain
49
Probable max storm (PMS)
rain over time
50
Probable max flood (PMF)
Greatest possible flood assuming complete coincidence of all factors that would produce the heaviest rainfall and max runoff
51
Intensity-Duration-Frequency (IDF)
Curves representing a localized relationship amoung intensity and duration
52
Standard Project Storm (SPS)
Greatest storm that may be reasonably expected
53
Standard project flood
design flood, estimated using rainfall-runoff modeling
54
TP-40
Rainfall frequency, depth of rainfall
55
NOAA
Rainfall frequency, yields depth of rainfall
56
Rational Method
Q=kCiA
57
Time of concentration
time for an entire water shed to contribute to runoff
58
Sheetflow
Less shallow, cannot exceed 300ft
59
Shallow
shallow, can exceed 300 ft
60
Rational method steps
1.find c and n values 2.Areas of each land type 3.tc for each flowpath P2 from TP-40 V from TR-55 tc from TR-55 ws 4. choose longest time 5. IDF to find i 6. plug into Q=kCiA
61
Factors affecting hydrographs
Intensity rainfall duration watershed size etc
62
Characteristics on flood hyrdrograph
slope roughness storage drainage intensity channel length above all to runoff
63
UHG
Unit Hyrdrograph depth of 1 in or 1 cm of Pe
64
DRH
Direct Runoff hydrograph
65
CN
Curve Number land use soil type antecedent runoff conditions
66
ARC
arc 2 = normal arc 1= dry arc 3 =wet

Hydro. Exam 1 Concepts (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions