I do appreciate the suggestion, but the fact of the matter is that I think this additional cost would turn this from a fair decision to a bad decision.
The only good thing about the property was the lake. I didn't care for the location (both the geographic location and the distance from my house), the land was a little close to neighbors (potential liability from dam breakage), there are restriction against hunting (I want to dove and duck hunt), etc.
The price per acre for the area is under $2k. I would have purchased this piece for over $4k/acre. Fixing the dam to safe standards would have increased the cost to me greatly, but would add little or no value to the property.
I'm well aware that I'll probably not come across a lake as nice as this one for anywhere near the price - especially with a mature fish population, but feel that I'll probably pay more down the road for a property with a smaller pond/lake (or even none existing), but that the property will be better for me and my family in the long-run.
I'm disappointed that this one didn't work out, but this extra cost (and ever present liability with neighboring properties) were sufficient to break the deal for me.