Chapter 13 (Environmental Geology)
Which has the highest hydraulic conductivity?
- Sand - Dense limestone - Gravel - Sandstone - Clay
Consumptive Use
A type of offstream use in which the water does not return to the stream or groundwater resource after use; the water evaporates, is incorporated into crops or products, or is consumed by animals or humans.
Karst Topography
A type of topography characterized by the presence of sinkholes, caverns, and diversion of surface water to subterranean routes.
Drainage Basin (Watershed)
Area that contributes surface water to a particular steam network.
A watershed, or _________, is an area of land that contributes water to a particular stream or river.
Drainage Basin
What is a problem with multiple instream uses of rivers and streams?
Each use requires different conditions.
Aquifer
Earth material containing sufficient groundwater that the water can be pumped out; highly fractured rocks and unconsolidated sands and gravels make good aquifers.
____________ streams tend to flow all year.
Effluent
Darcy's Law
Empirical relationship that states that the volumetric flow rate such as cubic meters per day is a product of hydraulic conductivity, hydraulic gradient, and cross-sectional area of flow; developed by Henry Darcy in 1856.
Desalination
Engineering processes and technology that reduce salinity of water to such a level that it may be consumed by people or used in agriculture.
What type of geologic material would make a good aquifer?
Fractured sandstone, sand, fractured granite, and gravel.
What is the name for any process that adds water to an aquifer?
Groundwater Recharge
What happens when water is pumped from a well?
Groundwater is discharged, a cone of depression forms, and the water table is lowered.
What is the definition of groundwater mining?
Groundwater pumping from an aquifer at a rate greater than replenishment.
The ability of a particular material to allow water to move through it is called _____.
Hydraulic Conductivity
The rate of groundwater flow is proportional to the...
Hydraulic Gradient and Hydraulic Conductivity.
________ water use does not divert or remove water from its source.
Instream
Why does groundwater move so slowly through clay?
It has low conductivity.
If water is so abundant on earth, why are water resources such a big deal?
It is not always available and abundant where people are geographically.
Wetlands
Landscape features such as swamps, marshes, bogs, or prairie potholes that are frequently or continuously inundated by water.
The water management philosophy put forth by ______ focuses on natural variability in water resources.
Luna Leopold
______ proposed a new philosophy of water management, based on the acknowledgement that groundwater and surface water are subject to natural variations.
Luna Leopold
Water Cycle (Hydrological Cycle)
Movement or transfer of water from one of Earth's storage compartments, such as the ocean, lakes, and the atmosphere, to another.
Water Management
Practice of managing our water resources.
In a watershed underlain by shale and sandstone, which rock type would you expect to have the higher drainage density?
Shale
Virtual Water
The amount of water necessary to produce a product, such as rice or, in industry, an automobile.
The water management philosophy put forth by Luna Leopold focuses on what natural variability in water resources...
The natural variability in water resources.
In what way does the vadose zone differ from the groundwater zone?
The vadose zone is unsaturated while groundwater is saturated.
The drainage density on clay soils is likely to have what relationship to the drainage density on gravel soils?
There is greater density on clay soils than on gravel.
How long does water remain in the oceans?
Thousands of Years
The _________ includes all Earth material above the water table.
Vadose Zone
Why is karst topography a concern for groundwater quality?
Waste disposed in karst areas can easily infiltrate into the ground.
Off-stream Use
Water removed or diverted from its primary source for a particular use.
If water is so abundant on Earth, why are water resources such a high concern?
Water resources are not necessarily where humans need them and when they need them
In-stream Use
Water that is used but not withdrawn from its source; for example, water used to generate hydroelectric power.
____________ are areas that are either inundated by water or in which the ground is saturated to shallow depths at least a few days in most years.
Wetlands
If we don't manage our water resources better we may be facing ___________.
a food shortage in the future
Which of the following is a type of instream water use? a) Hydroelectric power generation b) Thermoelectric power generation c) Consumptive use d) Irrigation
a) Hydroelectric power generation
All of the following statements about global water abundance are true, except _________. a) most of the Earth's water is suitable for human use b) most of Earth's water is found in the oceans c) water is plentiful on Earth d) water is often not available in the right place, at the right time, and in the right form
a) most of the Earth's water is suitable for human use
Which of the following is incorrect about an aquifer? a) The upper surface of an unconfined aquifer is called the water table. b) An aquifer is composed of water percolating through the vadose zone. c) An aquifer is in the zone of saturation. d) An aquifer is composed at least in part by precipitation.
b) An aquifer is composed of water percolating through the vadose zone.
All of the following statements are part of Luna Leopold's new water management philosophy, except ______. a) surface water should be used when it is available during wet years, and groundwater should be reserved for dry years b) we are much better prepared to handle water deficiencies than floods c) surface water and groundwater are both subject to natural flux d) excesses and deficiencies in water are natural and can be planned for e) groundwater can be pumped out at a rate exceeding the replenishment rate in dry years as long as we allow it to be replenished by natural discharge and artificial recharge during wet years
b) we are much better prepared to handle water deficiencies than floods
All of the following are advantages or beneficial uses of wetlands, except _____. a) they provide a buffer for erosion b) they filter pollutants from water c) they almost always are areas of groundwater discharge and thus generally not susceptible to pollution d) they are often highly productive areas for wildlife
c) They almost always are areas of groundwater discharge and thus generally not susceptible to pollution
Pumping of groundwater from a well creates a(n) ______ in the aquifer.
cone of depression
A(n) ______ aquifer is largely isolated from the Earth's surface above it.
confined
An artesian well is one that...
contains water
The global water cycle involves which of the following processes? a) Water evaporates from the ocean into the atmosphere. b) Water flows into the oceans. c) Water precipitates from the atmosphere onto land. d) All of the above are true.
d) All of the above are true.
Which of the following is true of karst topography? a) Karst topography can result in diversion of surface water to subterranean routes. b) Sinkholes often form in karst regions. c) Karst topography occurs in areas underlain by limestone. d) All of the above are true.
d) All of the above are true.
All of the following are methods for reducing water consumption, except _______. a) water conservation through the use of more efficient appliances b) more efficient agricultural irrigation methods c) water recycling by industrial companies d) use of alternative water supplies e) none of the above
d) use of alternative water supplies
Drainage basins are separated by the ______.
drainage divide
The boundary between drainage basins is called the...
drainage divide
Which of the following is an environmental effect of dams? a) Downstream of the reservoir, rivers and coasts are deprived of sediment, encouraging river erosion and coastal erosion on beaches. b) Land, with all its resources, is lost in the area flooded by the reservoir. c) Ecosystems are fragmented, as migrating fish are blocked from moving upstream of the dam. d) The reservoir traps sediment that is transported from upstream by streams that enter the reservoir. e) All of the above are true.
e) All of the above are true.
All of the following are considered wetlands, except _______. a) swamp b) marsh c) vernal pool d) bog e) permafrost
e) permafrost
A(n) ______ stream gains water from an aquifer.
effluent
True/False: A cone of depression forms when water is pumped from an unconfined aquifer, but not when the water is pumped from a confined aquifer.
false
True/False: Concerns over water resources focus on the lack of abundance of water on Earth.
false
True/False: Groundwater in karst systems is very well protected from pollution.
false
True/False: Groundwater mining in the oglala aquifer is a function of the very small amount of water contained in the aquifer.
false
True/False: Groundwater movement is proportional to porosity.
false
True/False: Runoff in areas of shale bedrock tends to be less that in areas of gravel because of the high porosity of shale.
false
True/False: The water table separates confined and unconfined aquifers.
false
True/False: Water use in the US increased exponentially from 1960 to 1995.
false
True/False: Wetlands contribute to poor water quality and harm flood control.
false
The ability of an Earth material to transmit water is called its ______.
hydraulic conductivity
The global ______ involves the transfer of water between Earth's water reservoirs.
hydrological cycle
A(n) ______ stream typically lies above the water table.
influent
______ water use does not divert or remove water from its source.
instream
Vegetation decreases runoff by...
intercepting rainfall and slowing its fall to the ground
Surface water and groundwater are...
interconnected systems
______ and thermoelectric generators are the primary consumptive users of fresh water.
irrigation
What factor has contributed to the drying up of streams and the intrusion of ally groundwater in the Long Island area?
overpumping of groundwater
Groundwater mining is accomplished by...
pumping that exceeds recharge.
Why is the sediment yield an important consideration in a discussion of water supplies?
sediment is a common water pollutant
Which of the following would likely serve as an aquitard?
silt
Why has water quality degraded in the Edwards aquifer?
the aquifer is recharged by rivers flowing into karst limestones
The vadose zone differs from the groundwater zone in what way?
the vadose zone is unsaturated, while the groundwater zone is saturated
True/False: Desalination is used only where alternative water sources are unavailable.
true
True/False: Hydroelectric water use is considered non-consumptive.
true
True/False: The velocity and depth of surface water flow influence the amount of soil or sediment the water can erode.
true
True/False: Water management in the Colorado River basin has implications both for human use of water and for river ecology in the Grand Canyon.
true
True/False: Water pressure is generally greater in a confined aquifer than in an unconfined aquifer.
true
______ is related to the amount of water necessary to produce a product.
virtual water
What is the dominant trend in water use in the US?
water use peaked in 1980
______ are areas that are either inundated by water or in which the ground is saturated to shallow depths at least a few days in most years.
wetlands
