water supply, use, and pollution

1. Ricky B. Acanto
Water Supply,
Use, Pollution
and Treatments

2. Basic information
• Water has a high capacity to absorb and store heat.
• Solar energy warms the oceans, stores huge amounts of heat which transfers to
the atmosphere producing weather
• Water is the universal solvent
• Water has a high surface tension
• Capillary Action of water
• Water is the only compound whose solid is less dense than its liquid
form.
• Ice floats
• Sunlight penetrates water to differing depths
• Photosynthesis below the surface for both plants and photosynthetic animals

3. Water
Supply

4. Brief Global Perspective
• We are facing a growing global water shortage linked to the food
supply.
• Global hydrologic cycle
• 97% of the earth’s water is in the oceans
• 2% is in the ice caps and glaciers
• Only 0.001% in atmosphere
• 99% of Earth’s water in the natural state is unavailable or unsuitable for
human use.
• Water is scarce in some parts of the world (ie: Middle East & N.
Africa)
• U.S. Water Resource Council estimates that water use in the U.S. by
2020 may exceed surface water resources by 13%

5. The Hydrologic Cycle

6. Ground Water and Surface-Water Flow System

7. Water Supply
• Depends on several factors in; the hydrologic cycle
• Rates of precipitation, Evaporation, transpiration, stream flow and subsurface flow
• Water Budget – the model used to balance inputs, outputs and storage and
understand water supply
• Average water usage:
• US:100gal/person/day
• Europe: 50gal/person/day
• SubSahara: 5gal/person/day
• Philippines: ?
• Ex: Missouri River flows at 8.4 trill.gal/yr
• It could handle 230 millions Americans
• This is not considering precipitation, runoff patterns, evaporation and droughts

10. Surface-Groundwater Interactions
• Withdrawal of groundwater reduces stream flow, lowers lake
levels and can change the quality of surface waters.
• Can change a effluent stream from perennial to an
intermittent influent stream.
• Diversion of surface water may deplete groundwater
resources.
• This may increase concentration of dissolved chemicals in the
groundwater due to lack of dilution from infiltrated surface water.

11. Water Use and
Conservation

12. • Off-stream use:
• water removed from it’s source for use and then returned
(industrial processes)
• Consumptive use – an off-stream use: water is consumed
by plants or animals
• Must balance the amt. of water withdrawn with the
health of the ecosystem
• In-stream use:
• the use of rivers for navigation, hydroelectric power
generation, fish and wildlife habitats and recreation
• Each use requires different conditions

13. Some Trends in Water Use
• Trends in freshwater withdrawals by water-use categories
suggests that:
• The major uses of water are for irrigation and the
thermoelectric industry.
• Water use for irrigation increased from 1950-1980. It
decreased and leveled off from 1985-2000
• due to better irrigation efficiency, crop type and higher energy
costs.

14. Water Conservation
• The careful use and protection of water resources
• It involves both the quantity of water used and its quality
• It is an important component of sustainable water use.
• Expected that a number of innovations (development of new
customers value through solutions that meet new needs),
will reduce the total withdrawals

16. Sustainable
Water
Management

17. • From a water supply use and management perspective,
sustainable water use defined as:
•use of water resources by people in a way that
allows society to develop and flourish into an
indefinite future
•without degrading the various components of the
hydrologic cycle or the ecological systems that
depend on it.

18. General Criteria
•Develop water resources in sufficient volume to
maintain human health and well-being.
•Provide sufficient water resources to guarantee the
health and maintenance of ecosystems.
•Ensure minimum standards of water quality for the
various users of water resources.

19. Groundwater Sustainability
• Sustainability involves a long term perspective
•For groundwater even longer
•Effects of pumping might not be seen immediately
•Long-term approach involves balancing withdrawal
with recharge

20. Water Management
• Management of water resources is a complex issue
that will become more difficult as demand for water
increases in the coming years.
• Options for minimizing potential problems:
• Alternating water supplies and managing existing supplies
better
• Towing icebergs
• As price goes up many innovative programs are possible.

21. A Master Plan for Water Management
• New management philosophy is that surface water and groundwater are
both subject to natural flux with time.
• In wet years, there is plenty of surface water, and the near-surface groundwater
resources are replenished.
• During dry years, specific plans to supply water on an emergency basis must be in
place and ready to use.
• Advanced planning may include
• Drilling to wells that are presently isolated
• Reuse of waste water
• Develop surface water and use groundwater in dry years
• In wet years pump excess surface water underground to recharge groundwater

22. Dams and the Environment
• Dams and their accompanying reservoirs generally are
designed to be multifunctional structures.
• Used for recreational activities
• Generating electricity
• Providing flood control
• Ensuring a more stable water supply
• Often difficult to reconcile various uses at a given site.

23. Benefits of Dams
Water storage
Flood control Floods affected the lives of 65 million people between
1972 and 1996.
Irrigation Dams contribute to 12-16% of world food production.
Electrical Power Generation 19% of the worlds total electricy supply, in 150
countries. 24 countries depend on dams for 90% of
their power supply.
Improved navigation Stabilized annual flows
Improved domestic water availability In 1990, over a billion people had access to less than
the minimum required of 50 litres per person per day.
Recreation Fishing cab be improved esp. in lakes but also in rivers
with introduced species, leisure (e.g., boating on lakes,
extended rafting season on the Colorado River)
Ecological Increased riparian vegetation if dam discharges are
steady

24. Negative Issues with Dams
Ecological disruption Fragmentation of 60% of the worlds rivers;
Disruption of movement of species (e.g., destruction
of up to 75% of riparian bird species on the
Colorado)
Destruction of riparian vegetation if discharges are
irregular, e.g., peak-power of flood control types of
operations; loss of beaches and marshes
Groundwater table effects
Sedimentation behind dams
Erosion downstream by sediment-starved waters
Flucuation vs. steady releases Flucuations strand fish, reduce habitat for larval
native fishes; deny access to tributaries;
Clogging of rivers Peak floods required to clear channel may be
eliminated

25. Global Water Shortage Linked to Food Supply
• As human population grows there is growing concern that
there won’t be sufficient water to grow the food to feed 8-9
billion people.
• Food shortage linked to water resources a real possibility.
• Water also linked to energy (fuel to pump) as energy cost goes up so
does cost of food.
• Solution
• Control human population growth
• Conserve and sustain water resources
• Need to be proactive now before significant food shortages develop.

26. Water Pollution

27. • How is water pollution defined?
• The degradation of water quality.
• What are some of the common water pollutants?
• Heavy metals, sediment, certain radioactive isotopes, heat, fecal coliform, bacteria,
phosphorus, nitrogen, sodium, other useful elements, bacteria, and viruses
• What is the primary water pollution problem in the world today?
• A lack of clean, disease-free drinking water
• How many people are exposed to waterborne diseases worldwide?
• Several billion people
• Name 3 sources of Surface Water and 3 sources of Groundwater Pollution
• SURFACE: Runoff, accidental chemical spills, leaks of storage tanks/pipelines
• GROUNDWATER: Waste disposal site leakage, seepage from accidental spills,
saltwater intrusion into coastal aquifers

31. Biochemical Oxygen Demand (BOD)
• What is BOD and what are some sources of it?
• BOD is the amount of oxygen required for biochemical decomposition processes. It is used
in water quality management as a measure of the amount of oxygen consumed by
microorganisms. BOD is measured at discharge points into surface water, such as treatment
plants.
• Where does approximately 33% of all BOD in streams come from?
• Agricultural activities
• What about in urban areas (BOD)?
• Urban areas increase BOD in streams, especially areas with old sewage systems that have
stormwater and sewage in the same line.
• What is the relationship between BOD and dissolved oxygen levels? (What
happens when BOD is high?)
• When BOD is high, the dissolved oxygen content of water becomes low.
• What are the 3 zones of BOD:
• Pollution Zone: Where waste is decomposed; uses a lot of oxygen to break down
• Active Decomposition Zone: Where DO reaches minimum owing to rapid decomposition by
microorganisms as the waste is transported downstream
• Recovery Zone: Where DO increases and BOD reduces, because decomposing finishes and
natural system processes are replenishing oxygen

32. Waterborne Disease
• What is Fecal Coliform
Bacteria and where does it
come from?
• Bacteria that are usually
harmless that reside in the
intestines of animals. They
are present in waste and
they are used as an
indicator of disease
potential and feces.
Nutrients
•How do urban streams
get high concentrations
of Nitrogen and
Phosphorus?
• Due to fertilizers,
detergents, and products
of sewage treatment
plants.

33. Eutrophication
• Define Eutrophication:
• The process by which a body of water develops a high concentration of
nutrients, causing aquatic plants to grow and block light. This kills plants and
increases BOD when these plants decompose.
• What is the solution to artificial or cultural eutrophication?
• Ensure that human nutrient sources do not enter lakes and other bodies of
water by using phosphate-free detergents, controlling runoff, disposing of
wastewater, and using more advanced water treatment methods.
• What is a dead zone and how is it created?
• An area of water with low concentrations of dissolved oxygen (<2 mg/l) that is
created by cultural eutrophication that promotes light-blocking algae, which
kills organisms and increases BOD

34. Oil
• Which Environmental Act
was created after the
Exxon Valdez disaster?
• Oil Pollution Act of 1990

35. Sediment
• Why is sediment pollution considered to be a two-fold
problem?
• Because it results from erosion, which depletes land
resource, and it reduces the quality of water.
• What are some of the techniques employed by a
sediment control program?
• On-site erosion control, filtering

36. Acid Mine Drainage
• Define Acid Mine Drainage and explain how it occurs:
• Acid Mine Drainage is water with a high concentration of sulfuric acid
that drains from mines. This is made when pyrite mined from coal
rocks is dissolved in water.
• What is the general equation for acid mine drainage?
• 4FeS2+15O2+14H2O -> 4Fe(OH)3+8H2SO4
(Pyrite+Oxygen+Water -> Ferric Hydroxide+Sulfuric Acid)
• What site was once designated by the U.S. Environmental
Protection Agency as the nation’s worst hazardous waste site?
• The Tar Creek area in Oklahoma

37. Surface Water Pollution
• What are some point sources of surface water pollution?
• Pipes, outflows from sewage systems
• What are some non-point sources of surface water
pollution?
• Runoff from streets or fields
• What are the 2 approaches to dealing with surface water
pollution?
• Reduce the sources and treat water to remove pollutants or
convert them to forms that can be disposed of safely

38. Groundwater Pollution
• 75 % of the 175,000 known waste disposal sites in the United States may be
producing plumes of hazardous chemicals that are migrating into
groundwater resources.
• What is bioremediation?
• Using microorganisms that break down or consume a pollutant
• What are the 5 important points about groundwater pollution?
• Some pollutants are lighter than water, and thus float on groundwater;
• Some pollutants have multiple phases: liquid, vapor, and dissolved;
• Some pollutants are heavier than water and sink or move downward through
groundwater;
• The disposal method of a water pollutant must take account the physical and chemical
properties of the pollutant and its interactions with surface or groundwater;
• Emphasis should be put on preventing pollutants from entering groundwater in the
first place
• What is saltwater intrusion of well water?
• The migration of saltwater into wells and aquifers

39. Waste Water Treatment and Reuse

41. Wastewater Treatment
• How Septic Tank Sewage Disposal Systems work.
• Septic tanks store waste, separating solids and liquids and filtering the waste. It then dispels
the waste into the soil, and natural processes filter it until it is safe enough for other uses.
• What happens during primary treatment of sewage?
• Raw sewage is processed through a series of screens and filters that filter out sediment,
organic matter, and solids. All particulate matter forms sludge, which is transported to a
digester. 30-40% of BOD is removed.
• What happens during secondary treatment of sewage?
• Sludge bacteria is used to remove BOD in wastewater, and the process is repeated
thoroughly. The sludge is then dried and disposed of in landfills.
• When is advanced wastewater treatment used?
• When it is particularly important to maintain good water quality
• What are some of the risks associated with Chlorine treatment of wastewater that
is later discharged?
• The chemical byproducts that are produced with chlorine usage, which reduces fertility in
fish, and possibly humans

42. Land Application of Wastewater
• Explain the process of wastewater renovation and
conservation cycle.
• Wastewater could be used to supply plants with nutrients
by being filtered, and using the beneficial organic matter
on crops (waste is simply a resource out of place)

43. Wastewater and Wetlands
• How can applying treated sewage to wetlands be
helpful to the wetland ecosystem?
• Applying sewage to wetlands can treat water quality
problems such as municipal wastewater, stormwater
runoff, industrial wastewater, agricultural wastewater and
runoff, mining waters, and groundwater seeping from
landfills.

44. Water Reuse
• What is the difference between indirect and direct
water reuse?
• Indirect water reuse is planned, and direct water use is
pumped directly from a treatment plant to be used in
industry and activities.

45. Water Pollution and
Environmental Law

46. • P.D. 1067(1976) - Water Code of the Philippines
• adopts adequate measures to conserve and regulate the use of water
in commercial, industrial and residential areas. It also provides other
policy guidelines in water quality and management of water
resources.
• P.D. 984(1976) - The Revision of Republic Act No. 3931,
Commonly Known as the Pollution Control Law.
• It is hereby declared a national policy to prevent, abate and control
pollution of water, air and land for the more effective utilization of
the resources of this country.
• P.D. 600(1974) (amended by P.D. 979) - Water Pollution Control
• prohibits the discharge of oil, noxious liquid substances, and other
harmful substances into the country's inland and territorial waters.

47. R.A. 9275- Philippine Clean Water Act of 2004
• The law aims to protect the country’s water bodies from land-based
pollution sources.
• It provides for a comprehensive and integrated strategy to prevent and
minimize pollution through a multi-sectoral and participatory approach
involving all the stakeholders.
• Owners or operators of facilities that discharge wastewater are required to
get a permit to discharge from the EMB or the Laguna Lake Development
Authority.
• DOH will formulate guidelines and standards for the collection, treatment
and disposal of sewage as well as the guidelines for establishment and
operation of centralized sewage treatment system.
• The water district will provide water supply and sewerage facilities and to
connect existing sewage lines, subject to payment of sewerage service
charges/fees within five years following effectivity of this Act.

48. end