Depends on how much water is flowing, of course. Right now the LCRA is taking a lot water from the rivers to keep the lake levels constant - lots of evaporation this winter because of the warm weather (combined with the lack of rain). In general, the North Llano River up-stream from Junction is not divable. The South Llano, is spring-fed and has a constant flow, both rivers meet at Junction, and you'll find decent pools south of town. It's 70 miles or so from the junction of the two rivers to Lake LBJ. Now, there's not a big call for diving in the river, so there is no well-established area (unlike at the San Marcos, Comal, or Frio), so be sure to stay off private property, and out of fisherman's pools. After about twelve miles south (along US 377) you'll find no real access to the river, bordered on each side by ranches and very thick vegetation. The one area that you may want to look at is Junction City Park on Junction City Lake in Junction. Good access is available, and I have snorkeled there.
