You must be wondering , why water pipes burst during winter only . The water pipes burst in winter because of ANOMALOUS BEHAVIOUR OF WATER .Generally liquids expand on heating & contracts on cooling.Water however shows an exceptional behaviour below 4 degree C. If we cool water at room temperature we find that it goes on contracting but as the temperature falls below 4 degree C it begins to expand instead of contracting, conversely if water is heated from 0 degree centigrate to 4 degree C instead of expanding it contracts.

The anomalous behaviour of water plays an important role in the survival of aquatic animals & plants in cold countries.During winter season as the temperature decreases water at the surface of lakes, rivers, sea etc start contracting . As the water contracts it’s density increases & it sinks to the buttom.This process continues until the temperature of all the water in a lake or river falls to 4 degree C .Thereafter as the water at the surface cools below 4 degree C it expands instead of contracting & consequently it’s density decreases , as a result it remains on the surface of lake or river.The temperature of water in the surface goes on decreasing to 0 degree C & finally is converted into ice, while the water below the ice continues to remain at 4 degree C. As water remains at 4 degree C, fish & other aquatic animals remain alive.