Saving Water for upcoming Generation

I am a teacher of primary school in rural area of Bangladesh. In my school community I saw peoples collected underground water from tubewell for general uses. But 2/3rd water is vesting when they collected. almost 2/3rd population of the world live in water crisis. If we still vest underground water our upcoming generation will also be in water crisis. So I think As a global citizen I need to take action on it. I decide to insert equipment in tubewell for saving water from vesting. I want to establish a water treatment plant for school community for purify water pf open sources such as ponds, lakes, and rivers and supply to community peoples at free of cost and make awarness on it. I want to also establish a rain water harvesting system for using water in dry seasons and save underground water. I hope your kind help. thanks all