WATER POLLUTANTS

• Sewage/waste water;
• Fertilizers/Pesticides;
• Alien species
• Global Warming
• Atmospheric Deposition;
• Pathogens; from untreated sewage, storm drains, septic tanks, runoff from farms
• Petroleum;
• Radioactive substances;
• Heat;
• Siltation/sediments;
• Salinization- Increased salinization and salt runoff from irrigated farms causes salinization of major rivers.;
• Heavy metals cause unpleasant taste and odour to drinking water;
• Suspended particles like sediments

1. EFFECTS OF WATER POLLUTION.

Effects on Agriculture;-use of wastewater and polluted surface and groundwater which contaminate crops and transmit disease to consumers and farm workers; Depositions of deleterious chemicals in soil leading to loss of soil fertility;

Effects on Environment/ecosystems;-pungent smell,discolourisation; increased temps; contamination; change the pH; decreased oxygen; detergents that create a mass of white foam in the river waters; Enrichment of groundwater with salts, nutrients from irrigated lands; eutrophication/algal blooms-what is the effect on recreational activities,water treatment plants/water providers;loss of aesthetic value; Algae clogs our waterways.

Domestic effects;-toxic substances such as lead, mercury, cadmium, and chromium
or cyanide, which may affect the use of the receiving water for domestic use or for aquatic life.

• Effects on industry; boiler scales, Heavy metals cause unpleasant taste and odour to drinking water; Suspended particles cause unpleasant taste & discoloration to drinking water;
• Improvement of water quality- Removal of organic matthru aerobic decomposition; chlorination to remove bacteria, suspended solids; precipitation of salts, desalination etc during water treatment is expensive for polluted water;
• Increased salinization and salt runoff leading to salinization of major rivers.;
• Heavy metals cause unpleasant taste and odour to drinking water;

Suspended particles cause unpleasant taste & discoloration to drinking water;

Effects on animal health;

 Large scale death of aquatic and terrestrial animals; Reduced reproduction rate; Increased disease incidences; Imbalances created in secondary foodchains; Accumulation of bioaccumulative and nonbiodegraddable pollutants in animal bodies; Bioaccumulation eg of organochlorine pesticides; Biomagnification;Cause health hazards like impotence, cancerous tumours etc

CONTROL OF WATER POLLUTION

pollution caused by domestic effluents may be controlled by treating domestic waste, using biotechnology, banning the use of phosphate-based detergents, using plastic pipes instead of those made from lead, recycling gabbage, using biodegradable detergents.

Pollution caused by industrial waste may be controlled by treating/cooling industrial waste, carrying out environmental impact assessment before establishing industries

Oil spillage may be controlled by cleaning spilled oil biotechnology and penalizing the industry individual or companies which cause oil spills/water pollution

Pollution caused by agrochemicals may be controlled by using mechanical control of weeds, biological control of weeds and pests, biodegradable organic fertilizer herbicides, insecticides pesticides, organic farming educate farmers on the use of correct amount of agrochemicals