Congrats on the new land and upcoming pond. A good friend of mine sells real estate, primarily farms and ranches in the Brenham/Chappell Hill area. Business is booming for him as there seems to be a mass exodus from Houston for those that have the means. It seems we a have all figured out we can be productive without going to an office. Where at north of Houston are you purchasing?

In regards to the pond build, I haven't built one but this is the correct place for very knowledgeable people. My first recommendation would be subscribe to Pond Boss and start reading past articles written by Mike Otto. He also has a book - "Just Add Water" - that seems to get a lot of recommendations by the experts on this forum. You may be close enough to his stomping grounds to use him as consultant/builder.

There are lots of advantages to building from scratch. As Steve mentioned you probably won't find a lot of fans of islands but its your pond and just make sure you know the pros/cons. One pro obviously being zip lines. My recommendation, and it doesn't really involve the pond per se, is while you are at it and if you are going to have the island, you should run electricity and water - electricity for sure. You may not miss if you don't have it but if you do have it you will be very glad and it will give you lots of options to further enjoy your island

Aeration will be probably be a must for that depth and the island would be a great place for the compressor if you have power. It will ease the difficulty of installation and the layout considerably because the island is going to be in the middle. In fact, if you are building a platform for diving that is probably a great place for a diffuser as you probably aren't going to be too worried about the water below the base of the deck.

Good luck and let us know how it goes.