Underscoring the importance of rivers in the life of urban areas, Prime Minister Narendra Modi on Sunday urged various cities to organize annual 'River Festivals' and create awareness among the masses. Such river festivals - common in some European, African and South American nations - could create a new awareness about the importance and preservation of these important lifelines and inculcate the value of each drop of water on human beings, he said at the foundation stone ceremony for the ambitious Rejuvenation and Pollution Abatement of Mula-Mutha River projects in Pune, taken up under the Centre's National River Conservation Plan and the development of a River Front on the lines of Sabarmati River Front in Ahmedabad.