Water Pollution

Pollution from Sewage

• Poses a threat to public health
• causes nutrient loading into surface waters
• causes an increase in BOD which causes a decrease in DO

Monitoring Sewage

• Standard test for total coliform (TCOL) and fecal coliform (FCOL) bacteria
• Standards
• Drinking water - 1 coliform bacteria: 100 ml of water
• Swimming water - 200 coliform bacteria: 100 ml of water

Disposal of Sewage Sludge

ANAEROBIC DIGESTION

• Anaerobic bacteria break down organics into methane gas and CO2
• Methane is trapped and used to heat the digester to 95F
• END Product - soil conditioner for gardens (humus).
• Fertilizer - Sludge is rich in plant nutrients and can be dried and sold
• PROBLEM - sludge can be high in heavy metals and PCB (NYC Sewage)

Ocean Dumping Ban Act

• 1988 - barred ocean dumping of sewage at the 200 mile marker 
• All cities were in compliance by 1988 EXCEPT NYC

Water Pollution

Water Pollution Control Act

• EPA established regulations for the discharge of pollutants in the USA
• It gave EPA authority to implement pollution control programs
• Set ambient water quality standards
• funded sewage treatment plants

Water Pollution Control Act

• amended in 1977 and came to be known as the Clean Water Act
• The ACT does not address water quantity or groundwater, only water quality
• initially addressed point source, since 1980s has come to address non-point

Genetic Pollution

• Zebra mussel - 1986 larvae of zebra mussel arrive
• ballast water from  european ship

Zebra Mussel Distribution

Quagga Mussel

Quagga Mussel

• Invaded the Great Lakes when it hitch hiked its was from Russia
• More damaging than zebra mussel  - greater tolerance
• Concern it will enter Chesapeake bay & Florida

Bad News of Mussel Invasion

• No known predators
• out competes food supply of native shellfish
• clogs irrigation pipes
• shuts down water intake systems
• fouls beaches

Good News on Mussel Invasion

• filter feeds and improve water quality
• water clarity stimulates and promotes growth of SAV
• increase energy flow in aquatic environment and reduce waste matter

Water Hyacinth

Water Hyacinth

• 1 woman from Florida took 1 plant from an exhibit for her own pond
• reproduces rapidly and doubles population in two weeks
• Native to Central & South America
• It is now the #1 invasive aquatic weed in the southeast!

CHAOS = +FBL

Problems

• It has displaced natural specie of plants, fish and clogged ponds
• Scientists introduced the non-native predators
• Water hyacinth beetle
• Snail from Puerto Rico
• Grass Carp from Russia

Snakehead Fish

Gobi Fish

Thermal Pollution

• Heated water from industrial processes or nuclear energy
• Released into waterways
• DO drops
• organisms have limited tolerance range for temp variation

Thermal Pollution

• Heated water from nuclear power plants

Eurasian Water Milfoil

Effects

• decreases DO
• Increase metabolic rate of animals
• interferes with reproduction
• increases vulnerability to disease
• induces direct mortality

Radioactive Pollution

• wastes from mining of uranium and plutonium

Ways to reduce Water Pollution

• decrease volume of pollutants
• shift to pollution prevention instead of clean up
• replace organic based solvents and paint thinners with water based products
• reuse wastewater (grey water)
• set up artificial wetlands for treatment