CONSEQUENCES OF RAW SEWAGE & NITRATE

FERTILIZERS

SEWAGE

1. FROM HOUSE A. HUMAN WASTE B. KITCHEN WASTE 1. FOOD RESIDUE 2. DETERGENTS2. INDUSTRIAL WASTE A. ACIDIC & ALKALINE CHEMICALS B. TOXIC METALS ( Cr, Cu, Zn)

3. WATER POLLUTION

A. ANIMAL SLURRIES LEAKAGE FROM FARM WASTE

B. RUN OFF WTAER FROM FARM FIELDS ( ARTIFICIAL FERTILIZERS )

Raw sewage & nitrate polluted run off water discharged into a river causes:

1. SUSPENDED SOLIDS effect - reduction in penetration of sun - O2 demand increased during decomposition of organic material2. PHOSPHATES effect – eutrophication (rapid growth of algae)

3. HEAVY METALS

effect – toxic to aquatic organisms &

humans if drunk

4. MICROORGANISMS ( viruses, bacteria,

fungi, & protozoa )

effect – disease if drunk

5. DETERGENTS effects - foam on surface of water to affect aeration - eutrophication6. NITROGENOUS COMPOUNDS effects - NH4 are toxic to fish - eutrophication - algal bloom encouraged

- algal respiration at night increases

BOD (biochemical oxygen demand)

results if depletion of dissolved O2

in the water

- death in algal bloom results in

increase of BOD (while algae is

being broken down)

- certain blue-green bacteria

produce toxins during algal bloom

growth

- high nitrate concentrations and

toxic if water is drunk