Transcript 1. Surface water

Marking Period 2 Chapters
Chapter 6
Chapter 8
Chapter 9
Chapter 10
Water
Chapter 11
Water
 Water cycle = Hydrologic cycle
 1. Evaporation – when liquid turns to
water vapor
 2. Condensation – when water vapor turns
into liquid water
 3. Precipitation – any form of water that
falls from the clouds
 Water distribution
 Oceans – 97% (salt)
 Fresh water – 3%
 77% - ice caps and glaciers
 22% - ground water
 1% - other sources (lakes, rivers, etc.)
 1. Surface water – fresh water found on the
Earth’s surface
ex. Ponds, streams, rivers & wetlands
 Watershed – is an area of land where water
drains into a river
 Note: We are part of the Raritan River watershed
 2. Ground water – is water found beneath
the earth’s surface trapped in sediment and
rock.
 Water table – the level where rocks and soil are
saturated with water.
 Constantly rises and falls important in flooding
and wells
 (A well is a hole that is dug or drilled to reach
ground water)
 Aquifer – an underground formation
made of rock, sand or gravel that
contains ground water.
 Note: Important water sources for
personal use and agriculture
 See Pages 294-295, Figure 4
Groundwater and the Water Table
 Recharge Zone – an area of land through
which water percolates downward into an
aquifer
 Percolate = water moving downward
through soil
 Permeability – the ability of a rock or soil
to allow water to flow through it.
Water Use
 Number 1 use of water worldwide is
agriculture.
1. Residential – the average person in the US
uses about 80 gallons of water a day.
 Bathing, washing car, watering yard, toilet
flushing, cooking, drinking, washing clothes,
etc.
 Potable – water that is safe to drink
 Pathogen – organism that causes
diseases
 Most water must be treated in order to be
potable
 See Page 297, Figure 6
2. Industrial – uses 19% of water
3 ways water is used in industry
 To manufacture goods
 To dispose of waste
 To generate power (electricity)
 Number 1 use of water in industry
3. Agriculture
 #1 use of water – 67%
 Irrigation – method of providing
plants with water from sources
other than precipitation
Water Management
Three goals
1. Bringing in water to a dry area to
make it habitable
2. Creating a reservoir for recreation
or drinking water
3. Generating electric power
Methods of Water Management
1. Water diversion projects
 Used to supply dry regions with water.
 All or part of a river is diverted into a
canal that carries the water long
distances.
 Example: Colorado River
2. Dams and Reservoirs
 Dam – a structure built across a
river to control its flow
 Reservoir – an artificial lake
formed behind the dam
Benefits from dams
1. Flood control
2. Supply drinking water
3. provides water for irrigation
4. recreation
5. generation of electrical energy
Disadvantages of dams
1. Can destroy ecosystems
2. Displaces people
3. Dam failure
Solutions for The Future
 The most important thing that can be done to make
sure we have water in the future is to conserve water.
 In some places conservation is not enough to
prevent water shortages, so they have to consider:
 Desalination – the process of removing salt from
saltwater – very expensive & it uses a lot of energy.
 Transporting water – moving liquid water from one place
to another.
 Towing Icebergs – possible, but an efficient way to do
this is unknown
Water Pollution
 Water pollution – the introduction of
chemical, physical or biological agents
into water that degrade water quality and
negatively affect organisms that use the
water.
 2 Main Causes
 1. Industrialization
 2. Rapid human population growth
2 types of sources of pollution
1. Point-source pollution – pollution that comes
from a single identifiable source.
 Examples: Leaking septic tank, unlined
landfill, discharge from industry
2. Nonpoint-source pollution – pollution that
comes from many different sources that are
difficult to identify.
 Examples: run-off of pesticides & fertilizers,
run-off from streets, run-off from livestock
Pollutant Types and Sources
Water Treatment
 Wastewater Treatment (Sewage
Treatment)
 Wastewater is any water that contains
waste from a home or industry
 See Page 307, Figure 17
Steps of Waste water treatment
 Primary Treatment
1. Filtration – wastewater enters through pipes
and is filtered through a large screen to remove
large objects
2. Primary settling tank – wastewater is placed
into a large tank where solid particles settle to
the bottom after 24 to 48 hours.
 Sludge – solid, settles to the bottom
 Effluent – liquid at the top
 Secondary Treatment
3. Aeration Tank – the effluent is placed in a tank
with bacteria and air. The bacteria feed on and
breakdown any waste left in the water.
4. Secondary Settling Tank – bacteria and solids
settle to bottom and form more sludge.
5. Chlorination – chlorine is added to disinfect
the effluent before it is returned to a stream, lake
or ocean.