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Difficulty II
Length 0.1 Miles
Gauge San Marcos Rv at San Marcos, TX
Flow Range 100 - 400 CFS
Flow Rate as of: 51 minutes ago 149 [CFS]
Reach Info Last Updated 09/07/2018 10:46 pm

River Description

Rio Vista Park was once the site of a sloping 8-foot low-head dam with a chute in the middle that created a play hole at certain levels.  The dam, which was constructed in 1904, was badly damaged in the flood of 1998 and became structurally unsound, and in early 2006, it was extensively renovated and turned into a whitewater park with artificial rapids.  The new whitewater park, which opened on May 25, 2006, extended the 8-foot drop over three drops, spaced about 30 yards apart.  In addition to their recreational value, the second and third drops reduce the turbulence and velocity of the water coming over the original dam (the top drop), which further protects that structure.

The top drop (about 4') is the steepest and largest, and its behavior varies with the river level:

  • Low flows (generally < 150 cfs):  All of the river flow is funneled into a single one-boat-wide slide, which creates a surfable wave at the bottom.  The wave is more green and has less well-defined shoulders;  it is thus popular with river boarders.  It is front-surfable by kayakers, but a certain amount of skill is required to stay on it, unless a wave shaper is used.
  • Medium flows (generally 150-200 cfs):  The wave is in a transitional state.  At 170 cfs, it is known to form a green tongue only on surfer's right but more of a shoulder on surfer's left, thus requiring the surfer to spin.
  • Medium-high flows (generally 200-250 cfs):  Generally considered to be the optimal level for kayakers.  Sufficient water is flowing over the rest of the dam to build good shoulders around the wave and a tall, fluffy pile behind it.  The wave easily gives up spins but can be front-surfed as well.
  • High flows (generally > 250 cfs):  The wave becomes more of a wave-hole and is not as forgiving or predictable.
  • Very high flows (generally > 400 cfs):  The wave starts washing out.


The second drop (about 2') is shallower and creates a front-surfable, but not retentive, wave at low flows.  This wave is generally at its best at < 150 cfs, when the top wave is at its worst.  At higher flows, the second drop starts to wash out.  There is usually an ender spot and a small wave train below it.

The third drop, AKA "The Cabana Bowl" (about 2') is more of a ledge hole.  It is very shallow at low flows, but at higher flows, it becomes deep enough to give up loops.  It is known to be playable even at levels (> 400 cfs) at which the top hole becomes washy.

Above the first drop is a large section of flat water, perfect for practicing flat water moves and rolls.

Because it is spring-fed, the San Marcos River maintains a consistent flow year-round.  170 cfs is the historical average, but spring flows of above 300 cfs are possible during extremely wet years.  Generally, flows higher than this require a runoff event.  Even during extreme droughts, it rarely drops much below 100 cfs.  Except during runoff events, the river runs crystal-clear with a water temperature around 70 degrees.

During the summer months, the park is generally clogged with tubers and swimmers during daylight hours on weekends and after work on weekdays.  However, the park has artificial lighting, so many kayakers prefer to play here after dark once the tubers and swimmers have left.

Rapid Descriptions


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10 years ago

Beware of park being used as a public urinal during summer months.

Gage Descriptions

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Directions Description

This is a park-and-play waterpark. Shuttle will be via carry-up. Therefore, ignore the shuttle directions listed below. However, if you use the text entry box to enter your home or other starting address, you can get drive time/distance and directions to this location.

(While it just says "Zip", it will take "street address, city, zip" or lat/lng coordinates in almost any format.)

No Accident Reports



article main photo

County to Vote to Extend Closure on Guadalupe Tonight (TX)

Jason Robertson

The Comal County Commissioner's Court is taking measures that will restrict access to the Guadalupe River indefinitely. AW's primary objective on the Guadalupe is to restore access as soon as possible and to make sure that boater access does not impede on-going rescue and recovery efforts.



Mark Singleton


Mike Erwin


Roman Ryder


Revision #Revision DateAuthorComment
1209957 06/28/18 DRC
1210313 09/07/18 Mark Singleton drop instruction ad
1208249 08/30/17 DRC
1204983 07/10/15 DRC
1209787 06/09/18 DRC
1208250 08/30/17 DRC
1191624 11/10/08 Mike Erwin n/a
1204825 07/04/15 DRC
1204824 07/04/15 DRC
1201349 05/28/12 Roman Ryder
1204826 07/04/15 DRC
1204877 07/07/15 DRC