Agriculture and household waste waters
Agriculture and household waste waters are the severe and very common water pollutant throughout the world. Waste from these sources includes usually different harmful water crops and fertilizing materials such as nitrogen and phosphorus. These are speeding up pollution harmful crops growth and unwanted and possibly poisonous algae development.
Maybe the most serious example of harmful crop is water hyacinth. It can double it’s water coverage area in two weeks if/when the conditions are favorable. It is not only covering the water surface but it will make evaporation much stronger and faster. This will create lack of drinking or irrigation water among other harms.