Here is a picture of my 2nd attempt (I don't learn very easy) at constructing a dam...It lasted almost 2 months...another monsoon took it out....I used more rocks and filler the 2nd time.......I even added a rock spillway along with the tinhorn.....it wasn't meant to be....
View attachment 203372
You might have to go with 2 of the tinhorns and cement around them . We had a guy do some pond work for us and he used corrugated pipe for drainpipes. Washed them all out after water started going down the side door of them. Your problem seems to be too much water not enough relief from the 4’ footer. If you figure out how to control Mother Nature and her ways of destruction let me. She can be a ***** sometimes
Sent from my iPad using Tapatalk