Brettski :

Keep it simple is a good idea as long as it works as planned. I am not suggesting anything extra. As long as you have a basin to keep the sand from washing down slope into deeper water and away from the beach you should be ok . The fabric should keep the sand from mixing with the underlying dirt. If the top of the sand is even with the top of the dirt you will get much more silt on top of your sand than if the top of the sand is higher than the dirt but constrained by a berm. Think about a sand box in the yard. If you dig it out so that it is ground level when full it will get dirt in the sand quicker than if you buy a plastic sand box (above ground) and fill it with sand. So I guess what I am suggesting is to do exactly what you are planning but take the dirt from the core/trenching and use it to make a berm on the down slope end of the beach so that you can pile the sand up higher than the surrounding pond bottom. No extra work as you have to get rid of the dirt anyway. Might as well use it to your advantage. ewest