Second Water Review

Which of these is the greatest consumer of domestic water?

• toilets
• cooking
• bathing
• drinking

Which of the following statements about eutrophication and Dissolved Oxygen (DO) is correct?

• Nonpoint sources (such as farms and yards) contribute plant nutrients to waters which encourage algae blooms.
• Point sources (such as power plants and refineries) contribute heat which cause algae blooms.
• In eutrophication, algae blooms use up all available D.O.
• In eutrophication, D.O. is driven out of water by nitrates and phosphates.

Worldwide, most water is used for

• agriculture
• industry
• domestic use
• producing electricity

Why does a dead zone form at the mouth of the Mississippi each summer?

• Fertilizers used in spring take time to wash downstream.  The effects of eutrophication accumulate as the summer goes on.
• Louisiana has more farms in the state than states upstream such as Missouri.
• The warm summer waters drive out dissolved oxygen as water molecules gain kinetic energy.
• The combined effects of oil spills, warm temperatures and point source pollution combine each year.

This law sets standards on pollutants for community water supplies.

• Clean Water Act (CWA)
• Safe Drinking Water Act (SDWA)
• National Environmental Policy Act (NEPA)
• Oil Pollution Act

Acid measures this on the pH scale.

• exactly 7
• anything below 7
• anything above 7
• anything from 1 to 14

In a river ecosystem, dissolved oxygen concentrations drop quickly downstream from a point-source input of organic matter into the river due to

• increasing populations of mayfly and stonefly larvae
• increasing bacterial activity as organic matter decays
• decreasing bacterial activity as turbidity increases
• decreasing water temperature

Which of the following is not usually associated with eutrophication?

• algal blooms
• reduced photosynthesis in the water column
• increased heavy metal concentrations
• reduced dissolved oxygen  

an underground tank containing bacteria that treat waste water is a

• septic tank
• leach field
• water treatment plant

Which of the following would NOT be considered gray water?

• water from toilets
• water from dishwashers
• water from showers