Water Resources

Phreatophytes

Deep-rooted plants that access groundwater

Potential Evapotranspiration (PET)

Max evapotranspiration under unlimited water

Lysimeter

Instrument to measure evapotranspiration

Interception

Rainfall caught by vegetation

Stemflow

Water flowing down stems/trunks

Vadose Zone

Unsaturated soil above water table

Phreatic Zone

Saturated zone below water table

Macropore

Large soil pore facilitating rapid water movement

Water Table

Top of the saturated zone

Saturation Overland Flow

Surface runoff from saturated ground

Horton Overland Flow

Surface runoff exceeding infiltration capacity

Fog Drip

Moisture from fog collected by vegetation

Overdraft

Excessive groundwater withdrawal beyond recharge

Baseflow

Sustained streamflow from groundwater discharge

DNAPL

Dense Non-Aqueous Phase Liquid; sinks in groundwater

Superfund

Program for cleaning hazardous waste sites

Primary Porosity

Original pore spaces in rocks

Secondary Porosity

Porosity from fractures, dissolution

Pump and Treat

Groundwater remediation technique

Point Source Pollution

Identifiable discharge location

Non-point Source Pollution

Diffuse pollution sources

John Snow

Mapped cholera outbreak; father of epidemiology

Joseph Bazalgette

Designed London sewer system

Colorado River Salinity Control Act

Reduces salinity in CO River

Colorado River Compact

1922 water allocation agreement

Dry-humid Boundary

Climatic dividing line (approx. 100th meridian)

John Wesley Powell

Explorer, early water management advocate

Jedidiah Smith

Explorer of western U.S. rivers

Total Maximum Daily Load (TMDL)

Pollutant limit for waterbody

Progressive Price Structure

More usage = higher rates

Regressive Price Structure:

Lower cost/unit with higher use

Pump Storage Facility

Stores energy via water elevation (e.g., San Luis Reservoir)

Hoover Dam

Major dam on Colorado River

Glen Canyon Dam

CO River dam; Lake Powell reservoir

US Clean Water Act

1972 law for water pollution control

Cuyahoga River

Infamous for catching fire; inspired regulation

Flocculation

Clumping particles for removal

Desalination

Removing salts from water (e.g., reverse osmosis)

Potable Water

Safe for drinking

Consumptive Use

Water not returned to source

Fall Line

Geologic boundary with rapids/waterfalls

Mill Dam

Powers mills; modifies streamflow

Riparian Rights

Water rights for land adjacent to water

Prior Appropriation

"First in time, first in right" water law

‘State’ of Deseret

Mormon proposed state with water control

Freeboard

Distance between water surface and dam top

3 Gorges Dam

Major dam on the Yangtze River, China

St. Francis Dam

Failed dam in California (1928)

Teton Dam

Failed dam in Idaho (1976)

Columbia River and Grand Coulee Dam

Hydropower and irrigation in Pacific Northwest

Fish Ladder

Structure allowing fish to bypass dams

Channeled Scablands

Erosional features from Ice Age floods

Cadillac Desert (book)

Marc Reisner’s critique of western U.S. water policy

Water is for Fighting Over (book):

John Fleck's book on western U.S. water issues

Arch Dam

Curved dam transferring pressure to abutments

Gravity Dam

Uses weight to hold back water

State Changes of Water

• Melting, freezing, condensation, evaporation, sublimation, deposition

• Latent heat absorbed (melting, evaporation, sublimation)

• Latent heat released (freezing, condensation, deposition)

Five Unique Properties of Water:

• Latent heat transfer

• Universal solvent

• High specific heat

• Solid state less dense than liquid state

• Surface tension

Four Main Causes of Water Pollution:

• Sewage and wastewater effluent

• Garbage disposal

• Agricultural runoff

• Industrial discharges

Eight Factors Affecting Infiltration Rates:

• Soil texture

• Rainfall rate

• Soil compaction

• Vegetative cover

• Impervious cover

• Bioturbation (earthworms, etc.)

• Macropores

• Soil frost

Three Ways to Measure Stream Velocity:

• Velocity Head Rod method

• Wading method

• Dye tracing

Five Physical Flood Control Measures:

• Levees

• Flood walls

• Dams and reservoirs

• Channelization

• Channel diversion (spillways)

Darcy’s Law

Land Subsidence – Causes and Effects:

• Causes: Groundwater over-pumping, mining, drainage of organic soils

• Effects: Infrastructure damage, reduced aquifer capacity

Salt Water Intrusion – Causes and Effects:

• Causes: Excessive groundwater withdrawal near coasts

• Effects: Contamination of freshwater supplies

Dye tracing in karst systems

Used to determine flow pathways and travel times

Calcite Reaction in Limestone

• CaCO3 + CO2 + H2O → Ca²⁺ + 2HCO₃⁻

Karst watershed features

• Flow in karst aquifers occurs mainly along solutionally enlarged fissures and conduits, rather than as diffuse intergranular flow

• Fissure and conduit-flow systems are characterized by large diameter openings and high flow velocities where Darcy’s is not valid

• Traditional concepts such as “drainage divides” and the “water table” are difficult to define for karst aquifers

• Flow divergencies in karst aquifers are common and may vary depending on stage

Drinking water treatment steps

• Pre screening at lake intakes, before pumping uphill to treatment facility

• Flocculation

• Sedimentation

• Filtration

• Disinfection

• Storage and distribution

Wastewater treatment steps

• Primary (screening and sedimentation)

• Secondary (Biological treatment)

• Tertiary (advanced filtration, disinfection)

Urban Stormwater Strategies

Green roofs, retention ponds, permeable pavement, and bioswales

Water Quality Parameters

• Temperature: Affects DO, metabolism

• Turbidity: Clarity

• pH: Acidity/alkalinity

• Hardness: Ca/Mg content

• DO: Dissolved oxygen

• VOCs: Volatile Organic Compounds

• PCBs: Industrial pollutants

• Cryptosporidium parvum & Giardia: Protozoan pathogens

Waterborne Infectious Disease Categories

• Waterborne (e.g., cholera)

• Water-washed (e.g., scabies)

• Water-based (e.g., schistosomiasis)

• Water-related (e.g., malaria)

Water Sources - Southern CA

Water brought in from Northern CA and CO river and delivered via aqueducts

Center Hill Dam problems

• Leakage through limestone around dam

• Grouting done to prevent this

Aswan High Dam Consequences

• Increased crop yields

• Reduced soil fertility

• Disease outbreak

• Delta erosion

• Reduced fish harvest in the mediterranean