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Surface &
Groundwater Pollution In Developing Nations
Introduction
| Surface Water | Groundwater
| Population and Water Resources | Case
Studies | Water Education | Links
- Introduction - Surface & Groundwater
- The Hydrologic Cycle
- Water Basics
- Sea water 97.2%
- Fresh Water 2.8%
- Polar ice & glaciers 2.15%
- Groundwater 0.62%
- Lakes and Rivers 0.01%
- The Three Fates of Precipitation
- Infiltration
- The movement of water into rocks or soil through
cracks and pore spaces
- Runoff
- Water that flows over the land
- Transpiration/Evapotranspiration
- the release of water vapor to the atmosphere by
plants
- Infiltration capacity of the soil is controlled by:
- Intensity and duration of rainfall
- Soil saturation
- Soil texture
- Slope of the land
- Nature of the vegetative cover
- Main Sources of Water
- Surface Water
- Lakes, rivers, reservoirs
- Ground Water
- In the Earth, flows through fractures and pores
- Surface Water – Stream Valleys
- Flood Plains
- Periodic floods deposit rich soils
- Agricultural production on floods plains is followed
by urbanization
- Natural levees
- Forms as floods deposit coarse detritus near the river
- Naturally constraint the river except in the larger
floods
- Surface Water – Flooding
- Floods and flood control
- Floods are the most common geologic hazard
- Causes of floods
- Weather
- Human interference with the stream system
- Engineering efforts
- Artificial levees
- Flood-control dams
- Channelization
- Nonstructural approach through sound floodplain
management
- What is Groundwater?
- Water found in the pores and fractures of soil and bedrock
- Largest reservoir of fresh water
- Tends to be less polluted than surface water
- An important erosional agent
- Groundwater is often mildly acidic
- Contains weak carbonic acid
- Forms caverns at or just below the zone of saturation
- Karst topography on the surface
- Groundwater Terminology
- Belt of soil moisture
- Water held by molecular attraction on soil particles
in the near-surface zone
- Used by plants
- Excess water percolates down to the zone of saturation
- Zone of saturation
- Water not held as soil moisture percolates downward
- Water reaches a zone where all of the open spaces
in sediment and rock are completely filled with water
- Water within the pores is called groundwater
- Zone of aeration
- Area above the water table & below zone of saturation
- Includes the capillary fringe and the belt of soil
moisture
- Capillary fringe
- Extends upward from the water table
- Groundwater is held by surface tension in tiny passages
between grains of soil or sediment
- Water table
- The upper limit of the zone of saturation
- Variations can occur in the water table
- Depth is highly variable
- Varies seasonably and from year to year
- Shape is usually a subdued replica of the surface
topography
- Factors that contribute to the irregular surface
of the water table
- Water tends to "pile up" beneath high
areas
- Variations in rainfall
- Variations in permeability from place to place
- Groundwater Movement & Storage
- Factors
- Porosity
- Percentage of total volume of rock or sediment
that consists of pore spaces
- Determines how much groundwater can be stored
- Variations can be considerable over short distances
- Permeability
- The ability of a material to transmit a fluid
- Specific retention
- The portion whish is retained as a film on particles,
rock surfaces, and pore spaces
- Specific yield
- The portion which will drain under gravity
- In general,
- Porosity = Specific retention + Specific yield
- Aquifer - A zone of Earth material capable of supplying
groundwater at a useful rate from a well
- Aquitard - A zone of Earth material that holds water
but cannot transmit it fast enough to pump from a
well
- Getting Groundwater Out of the Ground
- Extraction Methods
- “Natural” Methods
- Springs, Hot Springs, & Geysers
- Man-made Methods
- Problems with groundwater removal
- Non-renewable resource
- Subsidence
- Contamination
- Sources of Contamination
- Natural Sources
- Bacteria and viruses
- Uranium, radium, arsenic, and fluoride
- Often naturally occurring in rock formations
- Human Caused
- Acid Rain
- Acid rain is caused by:
- CO2 from cars and power plants
- NOx from cars
- SO2 from power plants
- Agricultural / Industrial Run-off
- Leakage from waste disposal, treatment,
or storage sites.
- Discharges from factories, industrial
sites, or sewage treatment facilities.
- Leaching from pesticides and fertilizers
on yards or fields.
- Accidental chemical spills.
- Leakage from underground storage
tanks.
- Improper disposal of household wastes
such as cleaning fluids, paint, and
motor oil.
- Population & Water Resources
- Urban population
- The average size of the world's 100 largest cities
- ~0.2 million in 1800
- ~0.7 million in 1900
- ~6.2 million in 2000.
- Population & Water Resources
- More developed regions: 70.0%
in 1975 75.5% in 2000
78.5% in 2015
- Less developed regions: 27.0%
in 1975 40.5% in 2000
48.5% in 2015
- Urban water supply and sanitation
- Proportion of households in major cities connected to
piped water:
- World: 94%
- Africa: 43%
- Asia: 77%
- Europe: 92%
- Latin America / Caribbean: 77%
- North America: 100%
- Oceania: 73%
- Proportion of households in major cities connected to
sewers:
- World: 86%
- Africa: 18%
- Asia: 45%
- Europe: 92%
- Latin America / Caribbean: 35%
- North America: 96%
- Oceania: 15%
- Urban child mortality
- In the urban areas of low-income countries, 1 child
in 6 dies before the age of five. In areas poorly
served with water and sanitation, the child mortality
rate is multiplied by 10 or 20 compared to areas with
adequate water and sanitation services.
- Toilets and latrines
- Infectious diseases transmitted by human excreta:
- cholera,
- typhoid,
- infectious hepatitis,
- polio,
- cryptosporidiosis,
- and ascariasis
- Uganda Ministry of Health study
- 1995 – One toilet for every 328 students
- 2001 – One toilet for every 700 students
- Attributed to increased enrollment in schools
- 33% of 8000 schools had separate latrines for
girls
- Prevention / control
- Low population density areas
- On-site systems such as ventilated improved
pit (VIP) latrines, double vault composting
latrines, pour-flush toilets, and septic tanks.
- High population density areas
- Off-site sewage treatment plants
- Sewer systems
- Requires adequate infrastructure
- Low-tech waste stabilization ponds also
a low-cost option
- Water and health
- Diarrheal diseases
- 6,000 deaths per day
- mostly among children under five.
- How to prevent?
- WASH YOUR HANDS
- Malaria
- Over 1 million people die from malaria every year.
- About 90 percent of the annual global rate of deaths
from malaria occur in Africa south of the Sahara.
- How to prevent?
- Sleep under mosquito nets
- Schistosomiasis (worms)
- More than 200 million people worldwide are infected
by schistosomiasis.
- 88 million children under fifteen years are infected
each year with schistosomes.
- 80 percent of transmission takes place in Africa
south of the Sahara.
- Water pollutants from industry
- Some 300-500 million tons of heavy metals, solvents,
toxic sludge, and other wastes accumulate each year
from industry.In developing countries, 70% of industrial
wastes are dumped untreated into waters where they
pollute the usable water supply.
- Pressures on freshwater ecosystems
- Main threats to ecosystems from human activities
- Population and consumption growth.
- Infrastructure development
- Land conversion
- Overharvesting and overexploitation
- Release of pollutants
- Introduction of exotic species
- River pollution
- Every day, 2 million tons of human waste are disposed
of in water courses.
- 40% of water bodies assessed in 1998 in the United
States were not deemed fit for World distribution
of hydropower recreational use due to nutrient, metal
and agricultural pollution.
- 5 out of 55 rivers in Europe are considered
pristine
- In Asia, all rivers running through cities are
badly pollute
- Wetlands loss:
- 50% of the world's wetlands have been lost since
1900.
- More than 80% of the wetlands along the Danube River
have been destroyed since the start of the 20th century.
- The Mesopotamian Marshlands in the Tigris and Euphrates
river basins were devastated by damming and river
channelization.
- Biodiversity loss:
- Between 34 and 80 fish species have become extinct
since the late 19th century, 6 since 1970.
- At a global level, around 24% of mammals and 12%
of birds are classified as threatened.
- In the United States, 120 of 822 freshwater fish
species are considered threatened, representing 15%
of total fish species.
- Sharing Water Resources
- Conflict and cooperation
- There have been 1,831 interactions (both conflictual
and cooperative) over the last fifty years.
- The concept of 'virtual water' has been developed
which allows nations and states to share the products
and benefits.
- Case Studies
- Gujarat, India
- Physiography
- Salt deserts in Kachchh
- Wet & fertile in SE
- 2/3 of population engaged in agriculture
- Water Sources:
- Three perennial rivers flowing through South Gujarat
- One major non-perennial river flowing in the
central NW portion of the state
- Rainfall is errati
- Area is susceptible to drought
- Exacerbated by:
- rocky terrain,
- desert region,
- a 1600 Km long coastline and deteriorating
ground water quality
- The problem: Over extraction of groundwater
- The Result? Up to 40 meters drop in water table
- ~14,000 villages out of 18,500 villages suffer from
severe water scarcity every year.
- Poor can only afford “dug” wells –
10 m depth max
- 15 Districts ( more than 2000 villages) are affected
by fluoride, and 16 districts are affected by salinity.
- Gujarat Infrastructure Development Board
- Plans on utilizing groundwater as main water source
- Diversion of water in the South and Central regions
to the North
- Construction of check dams, percolation tanks, village
tanks, river beds etc. for the recharge of ground
water.
- Recycling and re-utilization of sewerage water in
big cities and towns
- Will this work? What about groundwater contamination?
- Bangkok, Thailand
- Physiography:
- Hilly to mountainous
- Low-lying delta region
- Water sources
- Lots of rain
- Lots of rivers
- The problem: Over extraction of groundwater
- The result? Land subsidence in Bangkok
- Up to 10 cm/year (now 1 – 2 cm /year)
- Due to government’s lack of planning
- Problems due to land subsidence:
- changes in elevation and slope of streams, canals,
and drains
- damage to bridges, road, railroad, storm drains,
sanitary sewers, canals, and levees
- damage to private and public buildings
- in some southern coastal areas, subsidence has resulted
in tides moving into low-lying areas that were previouslyabove
high-tide levels;cost of pumping storm water and sewage
out to Chao Phraya river and Gulf of Thailand.
- Government solution:
- Expansion of water work service to cover the area
- A pricing system to discourage excess ground-water
use
- Groundwater recharging
- Public information on water saving.
- Will this work?
- Aral Sea Basin
- Once a large Pleistocene salt water lake (4th largest)
- Located between Kazakhstan to the north and Uzbekistan
in the south
- Desert-continental climate
- Extreme temperatures, cold winters, hot summers,
and sparse rainfall
- Precipitation rate = evaporation rate
- Natural factors affecting the lake
- Inflow from rivers (4/5th of total inflow
- Increasing evaporation rates / decreasing rainfall
- The problem:
- Diversion of water for agricultural irrigation
- The result?
- Increased salinity
- Decreased volume
- Shrinkage of the Aral Sea, 1960–99
- Development of ecological crisis in the basin of
the Aral Sea
- Impact on Climate
- Used to regulate cold winds from Siberia &
moderate summer heat
- Now short, dry summers and long, cold winters
- Frequent dust storms
- Impact on Soils
- Desertification
- Loss of topsoil
- Dust storms transport pesticide-laden soil to
Arctic regions
- Farming without irrigation impossible
- Impact on cryosphere
- Deposition of dust and mineral-rich precipitation
= glacial melting
- Glaciers lost
- 1081 in the Pamir-Altay area
- 71 glaciers in the Zaili Alatau area
- Impact on cryosphere
- Loss of fresh water supply
- Loss of main atmospheric moisture condensators
of the region.
- Impact on inhabitation sphere
- People moving elsewhere due to pollution, lack
of drinking water, and loss of soil
- Pollutants include:
- oil hydrocarbons,
- phenols,
- heavy metals and minerals,
- and pesticides.
- destruction of fishery,
- the appearance of cancerogenic diseases,
- and changes in citogenetic indices
- Aral Sea Population Density
- Impact on biodiversity
- Historically:
- 500 kinds of birds,
- 200 species of mammals
- 100 species of fishes,
- thousands of insects and invertebrates.
- Pre-1960: 70 kinds of mammals and 319 types
of birds
- Today: 32 kinds of mammals and 160 types of
birds remain
- Fishing industry destroyed
- Impact on the social and economic spheres
- Region has the highest infant mortality rate
in the former USSR
- High level of maternity death
- Increase in TB, infections and parasites, typhus,
hepatitis, paratyphoid
- Loss of jobs, etc.
- Other problems
- Part of the area was a Soviet WMD testing site
- Bubonic plague
- Anthrax (live spores as of 1999)
- What is being done?
- Governments have tried to institute water-conservation
policies & encourage use of less water intensive
agriculture
- Region not stable, hard to implement
- Possible Solutions to Problems
- Improving the quality of irrigation canals;
- Installing desalination plants;
- Charging farmers to use the water from the rivers;
- Using different cotton species, which use less
water;
- Melting glaciers in Siberia, and moving the
water to refill the Aral.
- Using fewer chemicals on the cotton
- In 1994 Aral Sea Basin Program (ASBP), with the
assistance of UNEP and the World Bank, was launched.
- The main objectives of the ASBP are:
- stabilize the environment of the Aral Sea
Basin;
- rehabilitate and disaster area around the
sea;
- improve management of land and water resources
in the basin
- build capacity of institutions at all levels
to plan and implement these programs
- Will the Aral Sea be saved? Should it be saved?
- Water Education
- Educating the public is key to insuring good water quality
& supply
- Problem:
- Politics
- Literacy rates
- Prejudices
- Primary school
- Will it work?
- Wikipedia, the free encyclopedia (http://en.wikipedia.org/)
- Surface & Groundwater
- Population & Water Resources
- Case Studies
- Water Education
Introduction
| Surface Water | Groundwater
| Population and Water Resources | Case
Studies | Water Education | Links
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