Doesnt matter since youre only using a single section of pipe but the bell ends should always go on the "upstream" end. Also a good idea to scrape the grass and topsoil off the dig are before digging out the clay so you can keep it separate... unfortunately, fixing holes from the backside of the dam is unlikely to work. Any water that has infiltrated that far will usually always find another route once plugged
Doesnt matter since youre only using a single section of pipe but the bell ends should always go on the "upstream" end. Also a good idea to scrape the grass and topsoil off the dig are before digging out the clay so you can keep it separate... unfortunately, fixing holes from the backside of the dam is unlikely to work. Any water that has infiltrated that far will usually always find another route once plugged