You could still collect water from the domed roof. As you complete you dome house, dig a trench all round the house say 1.5feet deep and two feet wide, put some tarpaulin lining at the bottom and then fill with aggregate/ chip stone. This will work like what they call French drain. From this trench create another trench same depth with trench sloping 1% out which then you will install a pipe that will transfer the water collected from the trench to the underground tank that you would also have to construct. The tank can be at any distance provided you have your slop to drive the water to the tank. The tank should have a sump and overall floor sloping towards the sump which will collect the dirt if any. The water should clear once collected and then install your solar pump, and can do whatever you want there because you would be sorted with water issue.
