When I am dead, I hope it is said;

When I mentioned this to someone else, and lamented the lack of available fill dirt in the region, he responded with "Well, the Mississippi River carries a few tons of silt by every what, hour?"

I'd think that the level of Lake P*mumble* would be the absolute minimum, and then you'd still be sitting below the river by a considerable amount. *Optimally*, bring it up to river level.