You could increase the height of the dam. You'd have to close off the existing drain pipe and be sure the new dirt is compacted well. However, I think raising the dam would only make the pond deeper near the damn. You'll just be extending the shallows further back onto your property. If the site is close to your property line, make sure you don't back water up onto your neighbor!

Why do you want to go deeper to begin with? Is the bond going dry? Does the weed problem get out of control? It sounds like the fish are doing fine and the carp are taking care of the weeds. Doesn't sound like a huge problem to me. I'd just manage the lake and start fishing it!

You may want to consider a new lake site if you want one that is deeper. With 70 acres it would be nice to have more than one pond. You'd not only have more water to fish, but you could move bass from one pond to the other, which will help keep the gene pool fresh.

Check with a professional in your area before you proceed. I live in Texas and go to the local NRCS.

0.6 acre pond / 13' max depth / Bonham, TX