Chapter 15 Flashcards
water mgmt for human consumption and industrial use (potable water) (3)
freshwater must be free of:
- dissolved salts
- plant and animal waste
- bacterial contamination
oceans
97.57%
freshwater
3%; not much available
- ice and glaciers = 78%
- groundwater = 21%
- rivers, lakes, and soils = 1%
reasons for water scarcity (6)
- antiquated water delivery systems: aging pipes = leaks/water loss
- depletion of resources
- mismanagement (bad distribution)
- industrial needs
- water conflicts/wars
- increasing human population
hydrologic cycle (4)
- evaporation: moves water to atmosphere
- evapotranspiration: moves water to atmosphere
- cloud formation
- precipitation
- groundwater, oceans, bodies of water
aquifiers
underground water resources
-porous rock that becomes saturated with water
unconfined
closer to surface
-top layer = more porous rock, recharged through rainfall
confined
- has layer of impermeable rock
- recharged in one location
water use
- toilets = 25%
- lawns, etc = 25%
- drinking/cooking = 2%
agricultural water use
ground and surface water used for irrigation of agricultural crops
types of irrigation (4)
- surface or flood irrigation: simple, but wasteful
- spray: continually pumps water; simple, but wasteful
- trickle: water directed at roots; work-intensive; expensive; efficient
- subirrigation: dig pipes in ground directed at roots; work-intensive; expensive; efficient
industrial water use
- most used for cooling (most is returned to source)
- some used for waste disposal
in-stream water use
- does not remove water
- used for hydroelectric power, recreation, and navigation
water pollution
addition of substances or energy to water which changes natural ecosystems or interferes with water use
types of pollutants (5)
- toxic chemicals (bioaccumulation and biomagnification)
- dissolved organic matter
- disease-causing organisms
- nutrients
- particles
point source
pollutants that can be traced to a single source
non-point source
pollutants that do not come from a defined source
clean water act (1972)
- sets water quality standards for surface water
- limits effluent discharges into water
pollution impacts on dissolved oxygen (3)
- decomposition of organic matter results in increased oxygen consumption
- pollution of water with organic matter or nutrients (resulting in algal growth) leads to increased biological oxygen demand (BOD)
- decreasing oxygen concentration impacts other aquatic organisms
sources of water pollution (6)
- municipal water pollution
- agricultural water pollution
- industrial water pollution
- thermal water pollution
- marine oil pollution
- groundwater pollution
municipal water pollution (5)
- stormwater runoff
- wastes from industries
- homes and commercial establishments
- fecal coliform bacteria
- pharmaceutical residues
agricultural water pollution (3)
- fertilizer and pesticide use
- soil erosion
- runoff from animal feedlots
industrial water pollution (2)
- disposal of wastes
2. mining activities
thermal water pollution (2)
- water is used for cooling and is returned to its source at higher temps
- changes in water temp can impact organisms and decrease dissolved oxygen content
marine oil pollution (4)
- accidents
- street runoff
- improper disposal of lubricating oil
- intentional discharge from tankers
groundwater pollution (12)
- agricultural products (pesticides, fertilizers)
- underground storage tanks
- landfills
- septic tanks
- surface impoundments
- mining waste
- road salt
- open dumps
- cemeteries
- radioactive disposal sites
- runoff
- excavation
water-use planning
metropolitan/urban areas must provide the following:
- water supply for human and industrial use
- wastewater collection and treatment
- stormwater collection and treatment
primary sewage treatment
goal: eliminate large debris in wastewater
secondary sewage treatment
goal: add bacteria to water that will decompose organic waste in wastewater
- allow sludge to settle at bottom and remove sludge
- then water is returned to waterways
