Bringing non-potable water into a building could be a real problem. (Heavy fines) Look for a way to keep the pump outdoors. As for the pipe sizes and layout, only you know what performance the pump is capable of. Some 1 HP pumps could justify larger pipes, like a 2 inch suction line. Drip irrigation from lake water is not a great idea. Better to figure on spray heads, so you can minimize the filtration you need. And find a good intake strainer for the suction line in the pond, and you can trade the foot valve for a check valve at the pump. A pressure tank might be useful, if you intend for the pump to be controlled by a pressure switch.