Sentence:  In view of the increasing shortage of usable surface and ground water in many parts of the Nation and the importance of finding new <WSD>sources</WSD> of supply to meet its present and future water needs , it is the policy of the Congress to provide for the development of practicable low-cost means for the large-scale production of water of a quality suitable for municipal , industrial , agricultural , and other beneficial consumptive uses from saline water , and for studies and research related thereto . 
Meaning of the word marked with <WSD> tags:  the place where something begins, where it springs into being