hydrology 2

Question 1

Is the water beneath the ground surface contained in void spaces.

Answer 1

GROUNDWATER

Question 2

is an underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well

Answer 2

AQUIFER

Question 3

is the level at which the groundwater pressure is equal to atmospheric pressure.

Answer 3

WATER TABLE

Question 4

Is a zone within the Earth that restricts the flow of Groundwater from one aquifer to another.

Answer 4

AQUITARD

Question 5

comprise layers of either clay or non-porous rock with low hydraulic conductivity.

Answer 5

AQUITARD

Question 6

an aquifer with the water table as its upper boundary

Answer 6

UNCONFINED AQUIFER

Question 7

aquifer found between two relatively impermeable layers

Answer 7

CONFINED AQUIFER

Question 8

it is a confined aquifer containing groundwater that will flow upward through a well without a need for pumping.

Answer 8

Artesian Aquifer/ well

Question 9

is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in the underground aquifers.

Answer 9

WATER WELL

Question 10

it is a narrow shaft drilled in the ground as part of groundwater site assessment.

Answer 10

BOREHOLE

Question 11

The imaginary surface that everywhere coincides with the piezometric head of the water in the aquifer.

Answer 11

PIEZOMETRIC SURFACE

Question 12

Is the portion of the stream flow that comes from groundwater

Answer 12

BASEFLOW

Question 13

natural or intentional infiltration of surface water into the ground system.

Answer 13

GROUNDWATER RECHARGE

Question 14

is groundwater that has remained in an aquifer for thousands or even millions of years.

Answer 14

FOSSIL WATER

Question 15

Surface waters on rivers

Answer 15

RIVER RUNOFF

Question 16

occurs during high intensity rainfall events

Answer 16

Infiltration excess runoff

Question 17

When rainfall intensity is less than soil infiltration rate, prolonged rainfall will saturate the soil and no more water could be held.

Answer 17

SATURATION EXCESS RUNOFF

Question 18

Point of rise, Rising Point of Inflection, Peak

Answer 18

Rising limb

Question 19

Rising Point of Inflection, Peak, Recession point of Inflection

Answer 19

Crest segment

Question 20

Peak, recession point of inflection, End point of recession

Answer 20

Recession limb

Question 21

It is the ascending curved portion of
the hydrograph.

Answer 21

Rising limb

Question 22

It shows the increase in discharge
from the catchment area in response
to the rainfall.

Answer 22

Rising limb

Question 23

Peak segment is shown by inverted U in
the hydrograph.

Answer 23

Crest Segment

Question 24

Highest concentration of runoff

Answer 24

Crest segment

Question 25

It is the highest point on the graph where the discharge is maximum.

Answer 25

crest segment

Question 26

The falling limb is the extension of the graph from the peak flow rate.

Answer 26

recession limb

Question 27

represents the withdrawal of water from the storage built up during the early phase of hydrograph.

Answer 27

recession limb

Question 28

types of hydrograph

Answer 28

unit hydrograph * storm hydrograph * snyder's synthetic hydrograph * annual hydrograph * monthly hydrograph * seasonal hydrograph * flood hydrograph

Question 29

a direct runoff hydrograph that is a result of one unit (one inch or one cm) of constant intensity uniform rainfall occurring over the entire watershed.

Answer 29

unit hydrograph

Question 30

a way of displaying how the discharge of a river can change over time in response to a rainfall event

Answer 30

storm hydrograph

Question 31

it is derived from model and experience, and it is used to simulate basin diffusion by assessing the basin lag based on a specific method.

Answer 31

snyder's synthetic hydrograph

Question 32

This enables the use of available data to determine a watershed's response to rainfall throughout the year, and thereby compute a year- round EIA

Answer 32

annual hydrograph

Question 33

It represents the variation of rainfall over a month.

Answer 33

Monthly hydrograph

Question 34

It shows the variation of discharge in a season.

Answer 34

seasonal hydrograph

Question 35

are graphs that show how a drainage basin responds to a period of rainfall.

Answer 35

flood hydrograph

Question 36

There are four ways that rainfall contributes to river runoff:

Answer 36

Overland surface runoff * interflow (subsurface runoff) * baseflow from groundwater * rainfall onto river channel

Question 37

is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil.

Answer 37

Overland surface runoff

Question 38

is relatively rapid flow toward the stream channel that occurs below the surface. It occurs more rapidly than baseflow, but typically more slowly than surface runoff.

Answer 38

interflow

Question 39

is the portion of the streamflow that is sustained between precipitation events, fed to streams by delayed pathways. It should not be confused with groundwater flow.

Answer 39

baseflow from groundwater

Question 40

Channel precipitation can be defined as rainfall and throughfall intercepted by the flowing stream channel and waterbodies, that without contribution to infiltration, subsurface flow, and ground water, incorporated into stream flow

Answer 40

rainfall into channel

Question 41

Overland surface runoff and interflow travel much faster than groundwater, hence they are combined into a term

Answer 41

Direct runoff

Question 42

-A SURFACE water flow that occurs as a result of rainfall.

Answer 42

Flow event

Question 43

-the inflows to any water system or area is equal to its outflows plus change in storage during a time interval.

Answer 43

water balance calculation

Question 44

-A portion of the precipitation seeps into the ground to replenish Earth's groundwater.

Answer 44

rainfall runoff

Question 45

-drawn to represent the characteristic time graph of decreasing total runoff

Answer 45

recession curve

Question 46

-the volume of fluid which passes per unit time

Answer 46

total flow volume

Question 47

-Water that flows over the ground surface directly into streams, rivers, or lakes

Answer 47

direct runoff

Question 48

portion of streamflow that is not directly generated from the excess rainfall during a storm event.

Answer 48

baseflow

Question 49

is the part of the total rainfall that contributes to direct runoff.

Answer 49

effective rainfall