Anything north of the Metroplex has our usual problems.
Many of the lakes have clay bottoms and for divers this has a direct relation to the visibility. Lakes with rock bottoms have better visibility- hence Lake Travis.
I would be careful of Lake Ten Killer- The State of Oklahoma is suing the State of Arkansas and numerous upstream chicken farmers. It seems that extreme amount of Chicken waste- Nitrates are getting directly into Lake Tenkiller and it is directly effect the quality of the water at Tenkiller.
Web-
http://www.scenicrivers.state.ok.us/News/Lawsuit_June_19-05.pdf
There are some interesting lakes north of the Metroplex, and over time I plan on hitting a few of them but the temperature of the lake becomes a restriction over time. Good luck with that- burrr.
Central Texas- The hidden Jewel.
From a divers point of view we want warmish water, excellent visibility and great places to dive. There are a number of places that are not developed or regularly dived in the Texas Hill country- some places are just remote- period. But if we look at the Edwards aquifer we can see where the water is traveling from and to.
Web-
http://www.edwardsaquifer.net/
Central Texas is a unique position and we can see from looking at the diagrams and maps the areas were the water in entering the aquifer and were it is exiting.
In the near future I would like to start looking in this area and start investigating certain tracks of land. This is the area out of the civilized built up zones that we will find something really neat. I am guessing it would be similar to Arkansas but warmer, and the higher rock content would help with clarity.
Texas Gulf Coast-
Ultimately most divers end up diving the Texas gulf and hitting the oil rig out there. As Diveblondy has mentioned their are great opportunities. Plus, we have the Sea Searcher II and Gulf Diving running trips to the Flower Gardens. A lot of divers I know use Texas lakes to keep proficient, and travel to the Gulf or South to Mexico for trips.
In Closing, Texas lakes while not being the best make Texas divers a hearty bread of divers. I have been diving with friends and we are drooling over 65ft of visibility in the Gulf were groups from Florida are only happy if it is over 100ft. So there are some good things that come out of having your training and being called a mud puppy.