Watersheds are sometimes called...

A hole dug into an aquifer to reach groundwater is called a

The least ranked primary use of freshwater around the world is...

The greatest ranked primary use of freshwater around the world is...

Which of the following was NOT part of the Clean Water Act?

Reservoirs are created by dams and include some lakes that are designed for human use. 

Globally, about 19% of our water is used for personal uses.

Most irrigation is inefficient.

Sewage pouring out of a pipe into a river would be considered point-source pollution.

Most of the oil released into the oceans by human activity comes from tanker spills.

Permeable layers of rock and soil that hold water. Once the water reaches the impermeable layers it cannot go any deeper.

Any area where surface water can soak into the ground and reach an aquifer below is called the...

Where groundwater is absorbed and cannot penetrate to any deeper layers.

If you live close to a water source, it is easier to do ________ compared to living in the desert where it must be transported from far away.

The buildup of salts in the surface layers of soil.

This type of pollution comes from discrete or specific locations.

This type of pollution comes from many places spread over a large area.

As a natural resource, freshwater is...

Which major category of water use would include watering grain to feed to livestock?

To help regulate river flow and to build a stable supply of water, engineers build

Reverse osmosis is a process often used for removing the following from water.

Which of the following is NOT an example of nonpoint-source pollution?

Which nutrient(s) is usually responsible for causing eutrophication in freshwater?

Harmful algal blooms are a result of what type of pollution?

What is the first step in a typical drinking-water treatment process?

Leaky underground storage tanks are a major source of what type of pollution?

Data indicate that our current rate of freshwater use is unsustainable in much of the world.

In an aquifer, the boundary between the zone of aeration and the zone of saturation is known as the...

________ seeps through the soul and becomes contained in underground aquifers.

A point of exit at which groundwater from an aquifer flows out on top of the Earth's crust and becomes surface water

A permeable layer that allows water and air to pass through to deeper layers.

Globally, about 69% of our freshwater is used for

The process of “making” freshwater by removing salt from saltwater, thus increasing freshwater supply.

Accounts for 97.5% of all the water on planet Earth.

Accounts for 2.5% of all the water on planet Earth.

79% of the freshwater on Earth is found in....

20% of all freshwater on Earth is found in...

1% of all the fresh water on Earth is found in...

What is the first step in the process of eutrophication?

What is the second step in the process of eutrophication?

What is the third step in the process of eutrophication?

What is the last step in the process of eutrophication?

Bodies of water with excess high nutrients mostly from nitrogen and phosphorus runoff causing low oxygen in the water

Unusually large amounts of sediment resulting from erosion transported by rivers and runoff

Occurs when pathogens enter a waterway, such as viruses, human or animal waste, bacteria, amoeba, protozoa, worms, etc.

Factories that use water to cool down hot machinery, then return that water to the source at a higher temperature

Occurs when harmful chemicals are released into waterways

Occurs when soil becomes saturated with water to the point that oxygen no longer gets in

Groundwater mining occurs when we withdraw groundwater slower than it can be replaced.

Groundwater depletion occurs as aquifers are depleted, water tables drop, and groundwater becomes