Im having a little trouble figuring this problem out!

I am tasked with providing water to 10 homes in a community. Theres an existing pump station that is powered with AC supply. I want to replace this pump with a more efficient one, and use solar panels and batteries to make the water supply to the community fully sustainable.

I have calculated that the community will consume a total of 12,500 liters of water per day. Obviously the pump required will need to be able to handle peak-hour water demand, and therefor a solar system and battery system that can store the power needed for pump demand both during the day, but also when sunlight is not available (for 15 days or so). Budget is massive and mostly irrelevant. How many solar panels would I need assuming a good quality industrial panel is 400W? How big of a pump would be needed to handle the peak demand? How big/how many batteries will be needed to supply power to the pump for 15>days? You can consider head specification irrelevant, assume pump is operating at peak efficiency.