Water Pollution

Question 1

How much of the surface of the world is covered by water?

Answer 1

3/4

Question 2

What is the function of the rising demands for water?

Answer 2

 Increasing populations

 Increasing developmental needs

Question 3

What is the knock on effect?

Answer 3

Upstream pollution in one country can potentially cause a epidemic in another.

Question 4

What are pathogens?

Answer 4

Disease causing organisms that grow and multiply host

Question 5

What are the 3 infections and their diseases?

Answer 5

Bacteria
 Cholera
 Dysentery
 Typhoid

Viruses
 Hepatitis

Parasitic worms
 Bilharzia

Question 6

What are waterborne infections?

Answer 6

Cholera, ingested

Question 7

What are water washed infections?

Answer 7

Scabia, cleanliness

Question 8

What are water based infections?

Answer 8

Bilharzia, contact

Question 9

What are water related infections?

Answer 9

Malaria, carries host

Question 10

What does DO, COD and BOD stand for?

Answer 10

Dissolved Oxygen content
Chemical Oxygen Demand
Biological Oxygen Demand

Question 11

What is the salinity of:

• Fresh Water
• Brackish
• Saline
• Seawater
• Drinking water

Answer 11

 Fresh < 1500
 1500 < Brackish < 5000
 Saline > 5000
 30000< Seawater < 34000
 Drinking water < 500

Question 12

What does the removal of fresh water cause?

Answer 12

Salinity Issues

Question 13

Why do Power Stations require excessive amounts

of cooling water?

Answer 13

To remove latent heat

from the Turbine Steam

Question 14

What are the Terms used to cover a range of chemicals
used to kill organisms we
consider “undesirable”?

Answer 14

 Insecticides
 Herbicides
 Rodenticides
 Fungacides

Predominantly used in agricultural industry.

Question 15

What is a common contaminant in ground water?

Answer 15

VOC’s

Question 16

What does aerobic mean?

Answer 16

In presence of oxygen, stable, non-objectionable

 CO2, SO4, PO4 and NO3

Question 17

What does anaerobic mean?

Answer 17

Insufficient oxygen, highly unstable, objectionable

 H2S, NH3, CH4

Question 18

When does NBOD exert itself?

Answer 18

After 5-8 Days

Question 19

What is the most common indicator of a rivers health?

Answer 19

DO

Question 20

When is there a lower chance for life to be sustained?

Answer 20

When DO < 5mg/l

Question 21

DO availability is a function of a number of things such as:

Answer 21

 Oxygen demand waste removes DO
 Photosynthesis adds DO daytime, remove at night
 Respiration of organisms remove DO
 Rising temp’s reduces solubility of oxygen in water (summer)

Question 22

What are the two key processes of a point source plug flow model?

Answer 22

 Removal of oxygen by microorganisms during biodegradation = DEOXYGENATION
 Replenishment of oxygen through aeration at the interface between the
river surface and atmosphere = REAERATION

Question 23

What is the rate of deoxygenation?

Answer 23

This is the rate at which microorganisms are removing oxygen from the water during biodegradation.

Question 24

What is the rate of reaeration?

Answer 24

This is the rate at which oxygen is being replenished.

Question 25

What is an oligotrophic lake?

Answer 25

 Clear water
 Little sediment
 Excess oxygen

Question 26

What is the difference between a oligotrophic and eutrophic lake when regarding photosynthesis?

Answer 26

 Oligotrophic lake: Photosynthesis at deep depths of lake

 Eutrophic lake: Photosynthesis at shallow depths of lake

Question 27

When does the density of water max out?

Answer 27

at 4°C

Question 28

What is DO affected by?

Answer 28

thermal stratification and

eutrophication