Is there a reliable web-site for locating dump stations? Some states have them co-located with rest areas. T/A and flying-J have them, but when you get off into the back roads etc . . how do you find one that is with-in reach of your travel plan?
In addition to the excellent advice so far, most (maybe even all) commercial campgrounds allow dumping at there facilities for transients. Most charge a fee - some reasonable and some not. A couple of owners I know told me that allowing public access was a condition of their sewer/septic permits.
