Garter snakes are good aquatic hunters.
And this snake sounds like a garter snake with its stripes.
They will get in and eat fish. Which can be
a handy thing in a small pond as canoodling fish
will overpopulate a pond if given half a chance.

That said, and since you live in Texas, I would do an online search of snakes
of Texas and make sure that is exactly what you have. Don't handle it
regardless.

If you find having a snake in the pond is a problem you can remove the rocks
it uses for cover and it will probably leave the area.

You can also catch a snake in a minnow trap baited with a live fish. Leave part
of the trap above water so the snake won't drown and then transport to a rural
area.
Your local animal control can advise you to do if the snake turns out to be a
cottonmouth.

Snakes get a lot of bad press. But you have to be careful and know what you are
dealing with.
I would not mind a garter snake visiting my pond.
Neat insight into nature that few people get to see. But when I suspected a
young rattlesnake made its way into my family room I caused all sorts of chaos!
;-)

good luck!
kathy :-)
A HREF="http://www.onceuponapond.com/"Once upon a pond/A