Summary of Water Resources and Water Pollution

  • Earth’s Water Budget

    • 97% saltwater, 3% freshwater
    • 2.59% of freshwater in ice caps/glaciers and deep groundwater
    • Less than 0.5% is readily available (soil, lakes, streams)
    • Continually replenished via the hydrologic cycle

  • Properties of Water

    • Hydrogen Bonds: Water (H₂O) has covalent bonds and hydrogen bonds among molecules
    • Boiling/Freezing Points: Boils at 100ºC, freezes at 0ºC at sea level
    • High Heat Capacity: Needs 4.184 J/gºC energy to raise 1g by 1ºC
    • Polarity: Universal solvent, easily dissolves many substances leading to pollution
    • Transparency: Essential for photosynthesis in aquatic plants
    • Ice Density: Ice floats on water; less dense than liquid water

  • Water Cycle

    • Renewable resource; atmospheric moisture replenishing faster than lakes/groundwater
    • Key processes: evaporation, condensation, precipitation, infiltration/percolation, runoff
    • Groundwater replenishment takes over a thousand years

  • Sources of Water

    • Surface water: lakes, rivers, seas
    • Groundwater: aquifers, water tables
    • Water can be vulnerable to overuse and pollution

  • Water Consumption

    • Community demand types: domestic, public, commercial, industrial
    • Average daily consumption: 60 liters per person; varies by region and season

  • Water Pollution

    • Definition: Water unfit for intended use due to contaminants
    • Major pollutants: lead, mercury, nitrates, phosphates, acids, persistent organic pollutants (POPs)
    • Impacts include disease transmission and disruption of ecosystems

  • Water Management

    • Protecting watersheds is crucial for clean water supply
    • Water treatment steps: coagulation, flocculation, sedimentation, filtration, disinfection
    • Wastewater treatment methods: sewage system and saltwater conversion challenges

  • Climate Phenomena

    • El Niño/La Niña: Affect precipitation patterns, leading to floods/droughts
    • El Niño causes critical water levels; La Niña brings heavy rainfall

  • Vulnerability of Water Resources

    • Inadequate access in many regions, seawater intrusion, land subsidence due to over-extraction
    • Drought leads to reduced supply; floods cause severe damage
    • Dead rivers due to pollution and urban waste

  • Prevention & Solutions

    • Regular monitoring and management strategies needed
    • Promote awareness of water use and pollution effects
    • Encourage watershed conservation and sustainable practices.