When you water like that, how long will the effects last assuming that there is a normal amount of rainfall? I have seen it done, but I really don't know much at all about that type of irrigation.
We leave dams in for about a month and then let ground dry out. A couple weeks early this year as weather conditions seem to be dryer and wanted to catch the runoff while it is there. A thunderstorm or two after that put icing on the cake.