1. CAUSES OF WATER POLLUTION  Domestic Waste-  Mere 0.1% impurities make domestic sewage water unfit  Domestic waste contain biodegradable matter  Readily decompose due to presence of microbes  Industrial Effluent  Chief water pollutant  Main Pollutant are salts of nitrate,phosphate,toxic metal ion,organic compounds  Can not removed easily

2. Effects of water pollution  Untreated Domestic sewage—Can cause outbreaks of oDysentery oTyphoid oJaundice o Cholera  Industrial waste---cause increase in conc. Of toxicants like heavy metals BIOMAGNIFICATION o This is due to non metabolism of heavy metals by micro organisms

3. Effects of sewage discharge  Microbes consume lot of oxygen after biodegradation of organic matter causing decline in dissolved oxygen  This results in mortality of fish and other aquatic creatures  It causes excessive growth of plank tonic algae- algal bloom  This algal bloom can be toxic to human and animals  It impart distinct colour to water bodies

4. Eutrophication  Natural aging of lake by biological and enrichment  Increase in the deposition of nitrogen phosphorus and organic matters result in increase in aquatic organism, plants.  Over the years debris pile up lake become shallow and warmer with warm water organism replacing those that thrive in cold water.  As a result floating plants convert lake into land.

5. Integrated waste water treatment Done in two stages Conventional ….by 1. Sedimentation 2. Filteration 3. Chlorine treatment  Using Microbes….Appropriate plants, algae, fungi and bacteria are seeded in Marshy lands.  Microbes absorb and assimilated the pollutant.  Marshes have sanctuary with biodiversities of fishes animals and birds

6. Ecological Sanitation For handling human excreta using dry decompositing toilets  Process is hygienic and cost effective  Human excreta is recycles as a natural fertilizer  Large quantity of water spend in disposing human waste is saved  Such toilets are are Eco-san toilets.  Found in Kerela and Srilanka

7. Control of water pollution Government of India has passed water prevention and control of pollution act in 1974.