If you live in an area where there is heavy rain and drainage that's not very good, stagnant pools of water are going to be a problem before too long.
Pools of water are ideal territory for insects to lay their eggs in and germs to proliferate. Mosquitoes, which can spread diseases like malaria, dengue fever and viral arthritis, flourish in still-standing puddles of water. A dangerous strain of the Escherichia coli (E.coli) bacteria also prefers wet environments. These bacteria can cause a life-threatening form of gastroenteritis.
Other diseases that can be spread by means of still-standing water, include typhoid fever, dysentery and cholera, to name but a few.
Water sources should be treated, covered up and drained. If you have a mosquito problem, mosquito larval oil can be poured onto the surface of stagnant water to kill off the pupae.
The pool of water should, however, be covered with a tarpaulin to prevent animals from drinking from it or children coming into contact with it.
Half a cup of chlorine bleach, added to stagnant water, should kill most germs.