unit 7 water pollution

hydrologic cycle describes

the mechanisms by which water moves throughout the Earth.

evaporate

Heat from the sun causes water to evaporate from rivers, lakes, oceans, or the soil

transpiration

Plant roots extract water from the soil and release some of it into the atmosphere through the soil and release some of it into the atmosphere through their leaves a process called transpiration

condensation

as the evaporated water moves up into the atmosphere it loses heat and condenses into clouds

run off

some of that water will form runoff, moving towards lower elevations and collecting into another body of surface water.

infiltration

the rest of the water soaks into the soil a process called infiltration.

about how much of the world’s water supply is fresh water?

3 percent

How much percent of freshwater is available on the surface?

1 percen

Water withdrawal

Measures the total amount diverted or withdrawn from a source including water that is returned

water consumption

measures only water that is permanently removed from a source.

What makes up the majority of both water withdrawal and consumption?

agriculture

water scarcity

Area can experience water scarcity meaning there is not enough access to freshwater or grow food.

Countries experiencing water scarcity tend to be

in highly populated and dry regions

zone of saturation

ground water is located in a region of soil called the zone of saturation where all of the spaces between soil particles are filled with water.

water table

the top of the zone of saturation is called the water table

aquifers

underground regions of soil or porous rock that are saturated with water

confined aquifer

If the aquifer is physically separated from the ground waterr it is called a confined aquifer.

recharge zones

regions where the water can infiltrate the soil and reach the aquifer are called recharge zones.

cone of depression

excessive water withdrawal can cause a lowering of the water table called

what is the result of the cone of depression?

This may cause nearby shalower wells to run dry.

saltwater intrusion

wells located near the ocean can experience saltwater intrusion as he ocean mixes with the groundwater.

subsidence

excessive groundwater consumptino can also lead to subsidence a compression and sinking of the zone of saturation

desalination

countries without access to groundwater or surface water may resort to desalination or the removal of salt from salwater

why is desalinated water more expensive

high energy costs of operating the plants

What is municipal tap water regulated by

Environmental Protection Agency

Standards are established within the

Safe drinking water act

bottled water is regulated by the

Food and Drug Administration instead of the EPA

artesian water

from a confined aquifer

distilled

water has been boiled and recollected contains no minerals

purified water

water probably tap that has been filtered by deionization or reverse osmosis

spring

from an underground formation that naturally flows to the surface

what are all of the water conservation techniques

water saver shower head, typical shower head, high efficiency washing machine, dual flush toilet.

pollutants

specific chemicals or groups of chemicals from specific sources with the specific environmental and human health effect

pollution

vague non descript for any substance that is harmful to the environment

water pollution

is the addition of any substance that degrades or lowers the quality of the water for living organisms

nutrient pollution

some waterways have seen a large amount of nutrient pollution from excess fertilizer that has runoff from nearby farms

eutrophication

excess nutrient pollution causes eutrophication or an overgrowth of algae

algae blooms caused by eutrophication

block sunlight from reaching underwater plants

As the algae and plants die

the dissolved oxygen levels of water decline

A decline in dissolved oxygen

causes the suffocation of large organisms like fish

hypoxic waterways

those bodies of water that are low in dissolved oxygen

oceanic dead zones are

areas of low oxygen in the world’s oceans caused by increased nutrient pollution

oxygen sag curve

a plot of dissolved oxygen levels versus the distance from a source of pollution usually excess nutrients and biological refuse.

biological oxygen demand

is a measure of the amount of oxygen that microorganisms, mainly bacteria, use to break down organic matter in water.

Higher BOD levels indicate more

organic pollution–as decomposers consume more oxygen to break down waste. If BOD is too high it can deplete dissolved oxygen in the water making it difficult for aquatic life to survive.

non point source pollution

Fertilizer runoff is an example of nonpoint source pollution because it does nto come from a single discharge lication

Faw sewage discharged from a large pipe would be an example of

point source pollution

watershed

the area of land over which all rain and other water sources drain into

Why did cuyahoga river in ohio carch fire?

due to a build up of oil on its surface

clean water act

is a law that set the allowable limits for various pollutants in surface waters.

any point source

may not discharge pollution into surface waters without a permit.

states are required to develop lists of impaired waers

that are too polluted or degraded to meet quality standards.

What are two causes of impaired waters

pathogens; bacteria and parasites that cause disease and nutrient pollution from fertilizer run off

sediment pollution

caused by anything that would increase erosion

increased sediment in waterways

can reduce light infiltration which affect primary producers like aquatic plants and algae, disrupting the entire ecosystem.

what happens when sediment settles

disrupting habitats, potential shelters buried under sediment, suffocating fish and amphibian eggs, increase water temps and thus decrease dissolved O2 content.

Industrial waste

heavy metals used for industry especially mining and burning of fossil fuels can reach the gorundwater impacting the drinking water supply

When elemental sources of mercury enter aquatic environments

bacteria in the water convert it to highly toxic methylmercury

Persistent organic pollutants

do not break down in the environment because they are synthetic carbon based mollecules can be toxic to organisms because they are soluble in fat which allows them to accumulate in organism’s fatty tissues

endocrine disruptors

are chemicals that can inerfere with the endocrine systemm of

what can endocrine disruptors do when absorbed in the body

decrease or increase natural hormone levels; mimic the body’s natural hormones; alter the natural production of hormones

Thermal pollution

occurs when heat released into the water produces negative effects to the organisms in that ecosystem

Thermal Pollution

Occurs when heat released into the water produces negative effects to the organisms in that ecosystem

what are the two categories of Ocean Pollution

Oil and Petroleum based plastics

name two big sources of oil discharge

natural seeps from oil deposits at the ocean floor; runoff from land, including leaking cars and improper disposal of used motor oil.

What do oil spills result in

oil spills in marine waters cause organisms to die tfrom the hydrocarbons in oil. Oil that floats on the surface of water can coat the feathers of birds and fur of marine mammals

Oil pollution act of 1990

Operators of oil tanekrs are responsible for all cleanup costs; increased the maximum liability for losses by businesses and private individuals; phased out single hulled tankers in favor of double hulled rankers which reduces losses in an oil spill by 4-6 times

Booms

large floating barriers to minimize spread of oil

skimming

boats equipped with floating skimmers remove the oil from the surface

bioremediation

using genetically engineered microbes to consume the oil.

chemical dispersion

applying chemicals designed to remove oil from the water by breaking it into small droplets

burning

setting fire to oil that is still floating on the surface

vacuums

suck up oil from shoreline

sorents

absorbent materials act like spongest to pick up oil but not water

non degradable

meaning that it does not fully decompose in the environment

exposure to sunlight will cause plastic to

break aprt into smaller pieces which accumulate in systems of rotating ocean currents called gyres

litter

litter that reaches aquatic ecosystems besides being unsightly can create intestinal blockage and chocking hazards for wildlife as well as introduce toxic substances to food chain

wastewater treatment

human sewage is a waste product that is unavoidable but it can be treated to minimize environmental impacts

primary wastewater treatment

holds the sewage in a large containment vessel heavy solids that sink to the bottom are removed as sludge may also be aerated to remove as much of the smell as possible

secondary wastewater treatment

a biological process in which bacteria break down organic matter into carbon dioxide and inorganic sludge which settles in the bottom of a tank then the tank is aerated to increase the reate at which break down the organic matter

tertiary treatment

the use of ecological or chemical processes to remove any polluutants left in the water after primary and secondary treatment

sewage overflow

sewage treatment platns have a limited amount of water but can be processed at any given time. If a flood snow melt or other excess water event occurs raw sewage may be dumped directly into the nearby water body.d