Chapter 9

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

Precipitation
Flowing artesian well
Well requiring a pump
Evaporation and transpiration
Confined
Recharge Area
Less permeable material such as clay
Runoff
Infiltration
Water table
Aquifer
Stream
Infiltration
Unconfined aquifer
Lake
Confined aquifer
Confirming permeable rock layer
Evaporation

• 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

Chehalis Basin

Precipitation
Flowing artesian well
Well requiring a pump
Evaporation and transpiration
Evaporation
Confined
Recharge Area
Runoff
Aquifer
Stream
Infiltration
Water table
Lake
Infiltration
Unconfined aquifer
Confined aquifer
Less permeable material such as clay
Confirming permeable rock layer

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

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

• Problems in the
• West
• Dry climate
• Drought
• Desiccation
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
Acute shortage
Adequate supply
Shortage
Metropolitan regions with population greater than 1 million

Wash.
Oregon
Montana
N.D.
S.D.
Idaho
Wyoming
Neb.
Nevada
Colo.
Utah Kansas
California
Oak.
N.M.
Texas
Highly likely conflict potential
Substantial conflict potential
Moderate conflict potential
Unmet rural water needs

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

• Natural phenomena
• Aggravated by human activities
• Rain on snow
• Impervious surfaces
• Removal of vegetation
• Draining wetlands
Living on floodplains
Reservoir
Dam
Levee
Flood wall
Floodplain

Large losses of water through evaporation
Flooded land destroys forests or cropland and displaces people
Downstream cropland and estuaries are deprived of nutrient-rich silt
Downstream flooding is reduced
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

• 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

• read section 9-4

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

• 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

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

• 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.

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 humancaused

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.

• Agricultural products
• Underground storage tanks
• Landfills
• Septic tanks
• Surface impoundments

• 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 nonpoint sources:
– runoff from streets
– improper disposal of used oil
– discharge of oil-contaminated ballast water from tankers

• 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

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

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

Changing land use changes vegetation and need for water

Change in land use also changes permeability

• 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

• 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.

• 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

• provide a flow of water sufficient to adequately support food fish and game fish populations in the stream (RCW
77.55.050)
• 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. 173-201 A WAC, following Federal Clean Water
Act)

• 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

Avoid headwater disturbance and leave vegetation

Allow floodplains to function as floodplains

• Markets and transfers
• Need to protect restored flows
• Enforcement

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

• The 1998 legislature passed ESHB
2514, codified into Ch. 90.82 RCW , to set a framework for developing local solutions to watershed issues on a watershed basis. Ch. 90.82 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.

• 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.

• 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