pumping station designs

How many MGD? 0.025, 0.50, 1.5?

What will the total head be?

What utility voltage is available at the pump station site?

These are a few relevant questions you should investigate to help you along with your homework assignment.

Power is power is power, there is no significant difference in that regard. But the issues raised by KJK are relevant in terms of the initial capital equipment outlay and the long term maintenance costs. HT (what we call MV here) has a higher capital outlay as a general rule and typically requires technicians that are specially trained, and that usually comes at an increased operating cost compared to LT systems. But if you already have HT equipment in your system elsewhere and therefore have those technicians, it may be less expensive to go that route. But then again, it's generally a LOT motor money to power up something under 400kW with HT because the control and distribution equipment has minimum sizes anyway, so below that minimum you are paying extra.

Good luck.