Built Water Systems Flashcards
What are the key water-related goals of the United Nations SDGs by 2030?
Achieve universal and equitable access to safe and affordable drinking water.
Provide adequate and equitable sanitation and hygiene for all, ending open defecation.
Improve water quality by reducing pollution and increasing recycling.
Increase water-use efficiency and address water scarcity.
What is the availability of fresh water globally?
A: Out of all the water on Earth, only a tiny fraction is available as drinking water. This is due to the limited availability of freshwater resources.
What are the key requirements for a water source?
Quantity: Sufficient water for extraction.
Quality: Water should be free of harmful substances and microorganisms.
Accessibility: It must be economically and practically feasible to extract and deliver the water.
What factors influence water use in different regions?
Population size and consumption habits.
Industrial and agricultural needs.
The state of technology in water distribution and equipment.
How does water quality depend on usage?
Domestic use: Requires clean, safe water, free of solids, odors, or unusual colors.
Industrial use: Varies based on industrial processes; may accept lower quality.
Agriculture: Must be free of substances that could harm crops.
What factors affect decisions about water extraction?
Natural: Topography, climate, and eco-system preservation.
Technology: Sophistication and robustness of equipment.
Economics: Cost and affordability of extraction and delivery
What are the three main components of a water supply system?
Extraction
Treatment
Distribution
Where do we typically extract water from?
Surface water: Lakes, rivers, and artificial dams.
Groundwater: Wells and aquifers.
Seawater: Through desalination (reverse osmosis or evaporation).
Reused water: Purified wastewater (e.g., in Singapore’s NEWater).
What types of contaminants can be found in extracted water?
Debris, organic material, pathogens, heavy metals, pesticides, and agricultural runoff.
What are the typical characteristics of surface water?
Often more polluted and requires advanced treatment.
Accessibility may vary with the seasons.
Utilizes natural flows for transport (rivers, canals).
What are the typical characteristics of groundwater?
Contains fewer suspended materials but may have minerals, metals, or gases like methane.
Quality depends on the geological formation and can be subject to depletion or saltwater intrusion.
What are some common treatment methods for groundwater and surface water?
Groundwater: Aeration, softening, and disinfection.
Surface water: Screening, coagulation, sedimentation, filtration, and disinfection.
What are the two most common methods for desalination?
Membrane filtration (reverse osmosis): Removes dissolved salts using pressure.
Evaporation: Uses heat to evaporate water, leaving salts behind.
What are key features of a water distribution system?
Pressurized to avoid leaks and maintain water quality.
Should distribute large volumes efficiently and prevent stagnation.
What are the two main purposes of water towers?
Act as reservoirs to balance demand fluctuations.
Maintain stable pressure in the local distribution system.
