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ENGR202 LECTURE 4 WATER POLLUTION - Coggle Diagram
ENGR202 LECTURE 4
WATER POLLUTION
HYDROLOGIC CYCLE (Cycle de l'eau)
A few states...
Biological water:
water coming from humans and organisms
Evapotranspiration:
evaporation and transpiration of trees
Permafrost:
State between solid and liquid
Losing permafrost = global warming since it cant be renewed
Freshwater is a small percentage of all the water in the world. Most of it is found in glaciers. Some of it from groundwater
Only 1.2% of it is accessible to us via lakes/rivers/swamps
Waterstress
Demand for water surpasses the amount available during a certain period
Indicates how sustainable a water source is in a given area
Causes
Overuse of water
Contamination oof water
Population growth
Climate change
Consequences
Less water
Conflict over resources
Health issues from lack of clean water
Less economic development
Loss of biodiveristy
WATER POLLUTION
water dissolves a lot of things and thus can get contaminated easily
Nonconventional pollutants
Color
(Water of a wackahh color, possibly coming from discharged from industries into the water)
Salt : Certain animals survive in specific salinities
Also an indicator of water density being offset
Thermal pollution:
Odd change in water temperature
Certain processes like photosynthesis only happen at a specific temperature
Priority pollutants
Specific chemicals
Comprised of:
Heavy metals
Pesticides
Volatile Organic Compounds (VOCS)
Polyaromatic hydrocarbons (PAHs)
Chloronated solvents
Phenol and phthalates
Conventional Pollutants
mostly groups
Biochemical Oxygen Demand (BOD)
Amount of dissolved O2 in water, used to break down organic matter and eat/survive
Dissolved O2 is obtained from
Diffusion
: Equilibrium @ the surface of water between water and oxygen
Aeration
: Movement in water in the form of waves and winds traps O2
Photosynthesis
from aquatic plants
More oganic matter needs to be dissolved = more oxygen needed
Introducing more organic matter into the ocean will make micro organisms use more O2 to eat (High BOD)
Eating requires O2 => less O2 in the water (
Hypoxia
) => less aquatic life
Eutrophication
Build up of N and P in water => more food for algae => obscuring light from water => increase BOD
Source
:
Sewage dischange
Industrial water
Detergents
Leads to
Hypoxia/Anoxia
=> Dead zones
Life cannot develop part from if ur anaerobic
Reduced biodiversity
Total Suspended solids, AKA Turbidity
Fine particles in water (what makes water less transparent)
High turbidity = less light in water = less photosynthesis = less dissolved oxygen
High turbidity = higher water temperature = lower dissolved oxygen (warm water holds less oxygen than cold water)
Fine particles like Silt, clay, organic matter, algae...
Fecal coliform bacteria
Specific type of bacteria that lives in the digestive track (E.coli!!!)
Mostly used as an
indicator
of the presence of other pathogens/bacteria (diarrhea, cholera, skin disease...)
Source
of fecal coliform
Untreated sewage
Wildlife waste
Improper watse disposal
pH
Most aquatic life like a range of 6.5 to 8.0 pH
Some consequences
pH
too low/too high
will endanger/kill aquatic life
will also make
pollutants more mobile
& easier to contaminate other plants/animals
toxic metals dissolve easier under a pH of 4 cus more H= ions will break bonds in them
Caused by
acid rain
and
disposal of pollutants
in wastewater
Oil and grease
Creates film on surface of water = less exchange of oxygen an air (diffusion)
Can be
Petroleum based
(crude il, gasoline) or from
animal/vegetable
fats from agriculture
Consequences
Harms fish/aquatic life
Degrades water quality
Also expensive to treat
Discharges
regulated from
Surface water
Storm water
Sewage and treatment plants
NOT from
Oil and gas exploration (drilling muds (breaking rocks for oil => waste comes out))
After above and underground oil/gas storage leaks
OCEAN ACIDIFICATION
Decrease of water pH due to human activitites like fossil buel
Larger amounts of CO2 in the air => more CO2 in the water
Bad for species who made their skeleton out of CaCO3
Reaction
:
CO2 + H2O --> H2CO3
H2CO3 --> HCO3- + H+
H+ + HCO3- instead of with Ca2+ and CO32- which = CaCO3