How can I install an overhead water tank and refill it for individual usage?

I live in a group apartment where there is severe water supply problem.
We have a common sump in basement which can be filled with water from external supply sources like water tanker trucks on payment basis.
Actually, I am looking for a solution which I can only individually utilize it.
I am planning to install a overhead tank on the terrace of the apartment and provide pipe lines additionally to my flat.
Now, if I want to refill the overhead tank with truck water supply tanker, how easily I can pump the water to the terrace?