1. Water Resources and Water Pollution
Chapter 9

2. Water Resources Water Earth’s surface is covered by 71% water
Essential for life – can survive only a few days without water

3. Supply of Water Resources
Small fraction (.014%) is readily
available for human use

4. Evaporation and transpiration
Water Cycle – continuously collected, purified, recycled and distributed
Evaporation and transpiration
Evaporation
Stream
Infiltration
Water table
Unconfined aquifer
Confined aquifer
Lake
Well requiring a pump
Flowing
artesian well
Runoff
Precipitation
Confined
Recharge Area
Aquifer
Less permeable material
such as clay
Confirming permeable rock layer

5. Watershed
A watershed describes the total area contributing drainage to a stream or river
May be applied to many scales
A large watershed is made up of many small watersheds

6. Chehalis Basin

8. Evaporation and transpiration
Stream
Infiltration
Water table
Unconfined aquifer
Confined aquifer
Lake
Well requiring a pump
Flowing
artesian well
Runoff
Precipitation
Confined
Recharge Area
Aquifer
Less permeable material
such as clay
Confirming permeable rock layer
Zone of saturation
(spaces completely filled with water)

9. Water sources
Surface runoff – 2/3 lost to floods and not available for human use.
Reliable runoff = one third
Amount of runoff that we can count on year to year
Groundwater
Zone of saturation
Water table – top of zone of saturation
Aquifer – water saturated layers of sand, gravel or bedrock through which groundwater flows.
Recharge slow ~ 1 meter per year

10. Use of Water Resources
Humans directly or indirectly use about 54% of reliable runoff
Withdraw 34% of reliable runoff for:
Agriculture – 70%
Industry – 20%
Domestic – 10%
Leave 20% of runoff in streams for human use:
transport goods, dilute pollution, sustain fisheries
Could use up to 70-90% of the reliable runoff by 2025

11. Too Little Water Problems in the West Dry climate Drought Desiccation
Acute shortage
Adequate supply
Shortage
Metropolitan regions with population greater than 1 million
US has plenty of water.
Much of it is in the wrong
place at the wrong time.
Most serious problems are
flooding, pollution,
occassional urban shortages

12. Water conflicts: Western US
Highly likely conflict potential
Substantial conflict potential
Moderate conflict potential
Unmet rural water needs
Wash.
Oregon
Idaho
Nevada
California
Utah
Montana
Wyoming
Colo.
N.M.
N.D.
S.D.
Neb.
Kansas
Oak.
Texas
Water and
Fish

13. Water conflicts: Global
Two main factors for water shortage: dry climate and too
many people. Many people live in hydro poverty – can’t afford clean
water.

14. Too Much Water: Floods Natural phenomena
Aggravated by human activities
Rain on snow Living on floodplains
Impervious surfaces
Removal of vegetation
Draining wetlands
Floodplain
Levee
Flood
wall
Dam
Reservoir

15. Deforestation and flooding

16. Using Dams and Reservoirs to Supply More Water: The Trade-offs
Large losses
of water through
evaporation
Flooded land destroys forests or cropland and
displaces people
Downstream flooding is reduced
Downstream cropland and
estuaries are deprived of
nutrient-rich silt
Reservoir is useful for recreation and fishing
Can produce cheap electricity (hydropower)
Migration and spawning of some fish are disrupted
Provides water
for year-round
irrigation of
cropland

17. Tapping Groundwater Year-round use No evaporation losses
Often less expensive
Potential Problems:
Water table lowering – too much use
Depletion – U.S. groundwater being withdrawn at 4X its replacement rate
Saltwater intrusion – near coastal areas
Chemical contamination
Reduced stream flows

19. Reducing water waste
read section 9-4

20. Solutions Sustainable Water Use
Not depleting aquifers
Preserving ecological health of aquatic systems
Preserving water quality
Integrated watershed management
Agreements among regions and countries sharing surface water resources
Outside party mediation of water disputes between nations
Marketing of water rights
Raising water prices
Wasting less water
Decreasing government subsides for supplying water
Increasing government subsides for reducing water waste
Slowing population growth

21. Pollution Source terminology
Point source = pollution comes from single, fixed, often large identifiable sources
smoke stacks
discharge drains
tanker spills
Non-point source = pollution comes from dispersed sources
agricultural runoff
street runoff

22. Types of Water Pollution from Table 9-1 p. 187
Sediment
logging, roadbuilding, erosion
Oxygen-demanding wastes
human waste, storm sewers, runoff from agriculture, grazing and logging, many others
Nutrient enrichment = Eutrophication
N, P from fertilizers, detergents
leads to increased growth in aquatic systems, ultimately more non-living organic matter

23. BOD
As micro-organisms decompose (through respiration) organic matter, they use up all the available oxygen.
Biological Oxygen Demand (BOD) Amount of oxygen required to decay a certain amount of organic matter.
If too much organic matter is added, the available oxygen supplies will be used up.

25. Eutrophication
Eutrophic – well-fed, high nutrient levels present in a lake or river
Oligotrophic – poorly-fed, low nutrient levels
Water bodies can be naturally eutrophic or oligotrophic, but can also be human-caused

26. Types of Water Pollution (con’t) from Table 9-1 p. 187
Disease-causing organisms
from untreated sewage, runoff from feed lots
Toxic chemicals
pesticides, fertilizers, industrial chemicals
Heavy metals
lead, mercury
Acids (to discuss later)
Elevated temperatures = Thermal Pollution
water is used for cooling purposes, then heated water is returned to its original source
any increase in temperature, even a few degrees, may significantly alter some aquatic ecosystems.

27. Groundwater Pollution
Agricultural products
Underground storage tanks
Landfills
Septic tanks
Surface
impoundments

28. Oil Spills
Exxon Valdez released 42 million liters of oil in Prince William Sound, contaminating 1500 km of Alaska coastline in 1989
Was the cleanup effective?
Most marine oil pollution comes from non-point sources:
runoff from streets
improper disposal of used oil
discharge of oil-contaminated ballast water from tankers

29. Growth of population
Supply & demand are in growing conflict – supply is finite – water management driven by values and needs
Increases demand/use of water
Increases land use and changes vegetation and permeability
Increases demand for instream values – instream flows are for people

30. The construction of dams have
slowed the once flowing Columbia
River into a series of lakes.

31. Agriculture uses approximately 70% of the water withdrawn
from our streams and rivers

32. Changing land use changes vegetation and need for water

33. Change in land use also changes permeability

34. Areas with 15 to 75 percent impervious surface are characterized as moderately developed. Areas with greater than 75 percent impervious surface are considered urban or highly developed. Areas with greater than 10% impervious surface have been proven to have a negative affect on groundwater and stormwater.

35. Water Rights Water collectively belongs to the public
Cannot be owned by individuals
Individuals or groups may be granted rights to use water
Legal authorization to use a predefined quantity of public water for a designated purpose.
Irrigation, domestic water supply, power generation

36. Water Rights
State law requires certain users of public waters to receive approval from the state prior to using water.
Any use of surface water which began after 1917 requires a water-right permit.
Withdrawals of underground water from 1945 requires a water-right permit.

38. Instream flows
Result – the more we know about stream ecology, the more we realize that all the water has instream value, meaning there is no surplus
Compromises and minimizing impact – thresholds for rate of impact
Other ways to achieve ecosystem goals – wider view, not just flows – watershed land management

39. Legal/political aspects of instream flow
provide a flow of water sufficient to adequately support food fish and game fish populations in the stream (RCW )
provide protection and preservation and where possible enhancement, of wildlife, fish, … and other environmental values … (RCW 90.54)
protect fish, game, birds, and other wildlife, recreational and aesthetic values and water quality (RCW 90.22)
antidegradation requirements of Washington’s water quality standards (Ch A WAC, following Federal Clean Water Act)

40. Instream flows
Other ways to achieve ecosystem goals – wider view, not just flows – watershed land management
Avoid headwater disturbance
Vegetation
Geology and topography
Maintain longitudinal and lateral connectivity
Avoid mainstem in-channel storage
Allow floodplain to function as floodplain

41. Avoid headwater disturbance and leave vegetation

43. Allow floodplains to function as floodplains

47. Flow restoration Markets and transfers Need to protect restored flows
Enforcement

48. Opportunities Parks and wilderness areas
Renewable natural resource management and harvest (forestry, grazing, secondary forest products)
Municipal watershed protection
Low intensity sustainable agriculture

49. Watershed Planning
The 1998 legislature passed ESHB 2514, codified into Ch RCW, to set a framework for developing local solutions to watershed issues on a watershed basis.  Ch RCW states: The legislature finds that the local development of watershed plans for managing water resources and for protecting existing water rights is vital to both state and local interests.

50. Watershed Planning RCW 90.82.005 Purpose.
The purpose of this chapter is to develop
a more thorough and cooperative method of
determining what the current water resource
situation is in each water resource inventory area of the
state and to provide local citizens with the maximum
possible input concerning their goals and objectives for
water resource management and development.

51. Watershed Planning
Each implementation plan must contain strategies to provide sufficient water for: (a) Production agriculture; (b) commercial, industrial, and residential use; and (c) instream flows. Each implementation plan must contain timelines to achieve these strategies and interim milestones to measure progress