ESTH 2100 Exam 4

What are the 6 components of the Water Cycle?

• Precipitation

• Interception

• Evapotranspiration

• Infiltration

• Groundwater

• Runoff

Precipitation

rain, snow, sleet, that moves from atmosphere to Earth’s surface

Interception

Shielding of soil from precipitation via plant branches, leaves or some other cover

Evapotranspiration

Water entering atmosphere because of heating and plant metabolism

Infiltration

Water hits the earth’s surface and percolates (enters) the soil

Groundwater

zone of saturation beneath the water table where all void space between sediment is filled with water

Runoff

overland flow of water, more of this is generated in areas with greater impervious surfaces or low permeable soils

Watershed

An area of land that drains into a specific waterbody

River Basin

often end at the mouths of river (where rivers met estuaries, seas, or oceans)

How many major river basins does NC have?

17 major river basins

What 2 river basins does Pitt County reside within?

Tar-Pamlico and Neuse River Basins

What % of earth’s surface is covered with water?

71% (about 70)

What % of Earth’s water is saltwater in oceans and seas?

97%

What % of Earth’s water is freshwater (total)

3%

What % of Earth’s water is freshwater in Glaciers and Ice caps?

approx. 2%

What % of Earth’s water is found in groundwater, lakes, rivers, soil, and the atmosphere?

1%

What % of available freshwater is in groundwater reservoirs?

97%

What % of adult human’s body is water?

65%

How much water is needed daily to maintain bodily functions?

1-3 Liters

What is the bare minimum amount of water needed daily for basic essentials?

50 liters/d

What is the largest category of water withdrawals in the United States?

Thermoelectric

What is second-largest category of water withdrawals in the United States?

Irrigation

How have water withdrawal trends changed in the United States?

Water withdrawals increased until the 1980s, it was stabilized until 2005, and have been declining since

The top 5 Water using states?

1. California: 32,000 mil gal/d

2. Texas: 28,000 mil gal/d

3. Idaho; 19,900 mil gal/d

4. Florida: 17,100 mil gal/d

5. Arkansas: 15,500 mil gal/d

What is NC ranked in water use by state?

ranked #9: 11,500 mil gal/d

Water stress

situation where a country’s available water falls below 4,600 L/d per person.

• >2 billion people living these conditions (8 billion people)

• could be up to 3.5 billion people by 2025

What % of world population is dealing with water stress?

25 percen

Water Scarcity

when level of a country’s available water falls below 2,700 L/d per person

Water scarcity is projected how many people in some arid and semi-arid regions?

as many as 700 million people

How many inches of rain does NC get every year?

50 inches

Which region in NC receives the most precipitation?

Western NC

How does urban development affect the water cycle?

Urbanization, there is a tendency to develop more land into residential, commercial, or industrial zones.

• turning forests, croplands, grasslands, wetlands, into the “built environment”

If you have a storm in a more suburban which are you more likely to experience more of?

there will more runoff

What happens as the % imperviousness increases?

the peak stream height increases and the runoff from watershed is delivered much quicker to the stream.

The 3 drought types

1. Meteorological

2. Agricultural

3. Hydrologic

Meteorological

based on rainfall

Agricultural

based on soil moisture

Hydrologic

base on streamflow or groundwater levels

Methods of data collection in measuring precipitation

• Weather stations

• rain gauges: manual (low tech), and automated (computer based)

• satellite and radar

What % of US water supply consists of groundwater?

25%

How many people (Americans and Worldwide) rely on underground sources for drinking water?

>50% of Americans ( >1.5 billion globally) rely on groundwater

Soil filtration

groundwater is usually cleaner and purer than most surface waters

• cheaper to treat for portable use

• digging wells cheaper than piping water from surface supplies to place of use

• over pumping and pollution now threats to groundwater supplies

Groundwater depletion

persistent lowering of the water table, withdrawal > deposits (net negative)

What is the world’s largest underground water reserve?

Ogallala Aquifer in the American West

• stretches across 8 states

• an example of excessive pumping

What are the 3 main factors of groundwater depletion?

• Excessive pumping can dry up lakes and rivers

• Reduction of recharge area: hard surfaces such as roads, parking lots, roof tops that do not allow rainfall to infiltrate the soil and recharge groundwater

• Saltwater Intrusion: migration of salt water from ocean to pumping wells due to excessive water level drops in freshwater aquifers

Confining Bed

largely impermeable layers that hinder water’s movement (clay)

Aquifer

permeable rock or sediments that transmit water easily (sand or gravel)

What is the #1 cause of groundwater contamination?

Petroleum leaks from underground storage tanks

What is the #2 cause of groundwater contamination?

landfill seepage

What is the #3 cause of groundwater contamination?

Septic systems

What is the largest global user and waster of water?

Agriculture (agricultural irrigation)

Water Consumption in the Industry

• huge amounts of water are needed by factories and power plants for processing, cooling, or steam generation

• Industrial water can be used substantially reduced by recycling

Water Consumption in Households

• public health considerations require that household water be of high quality, necessitating expensive treatment and distribution systems

• Urban planners are urging that water conservation become way of life

Water Conservation

reducing overall use, reducing waste, and recycling water for other uses

What are the main water efficient plumbing devices?

• toilets

• shower heads

• faucets

What is the single largest consumer use of water in homes?

Toilet flushing

• 24% of water use

Household practices to conserve

• Altered landscape practices

• Rain gardens

• Rainwater harvesting

• using low-flow plumbing fixtures and fix leaks

• turning off water when brushing teeth, shaving

Altered landscape practices

Use plants with low irrigation requirements

Rain gardens

directing runoff to landscaped areas in the yard that allow the water to infiltrate and potentially recharge the groundwater

Rainwater harvesting

the process of collecting, storing and using rainwater for water consuming activities such as irrigation, vehicle washing

Stormwater Management

• During less extreme storms, flooding can be mitigated by better managing stormwater runoff

• Certain practices are designed to reduce runoff and promote infiltration (example: rain gardens)

What are the two major types of water pollution?

• Point Sources

• Non-point Sources

Point Source of Pollution

enter waterways at well-defined locations (pipe, ditch, outfall)

Examples of point sources

• factories

• sewage

• treatment plants

• storm sewer outfalls

What are the two major categories of point sources?

sewage treatment plants and industrial discharges

Non-point source of pollution

Pollution from widespread sources, usually transported by runoff or erosion

Examples of non-point sources

• Agriculture

• construction activities

• urban runoff

• acid mine drainage

• airborne pollutants

What is the leading source of pollution in US waterways?

Agriculture