I want to run the exterior discharge from a sump pump into a solid PVC drain line, to be buried just below the surface, probably. Is 3" PVC drain line probably adequate, or would 4" PVC be better? This pipe will run approximately 100 feet, and be connected to a catch-basin and its drain line. Sump pump cycles on and off about once a minute, more or less, for much of the year. We have cold winters, averaging about 60" of snow a year. Would 4" PVC be less prone to have freezing issues? Please advise. Thank you.