What is the deepest non-lake water you've found in North Texas?

I found a canal/pond in DFW. I was expecting 6-10ft but was surprised to be sitting in 30ft.

How common is that?

Lots of that around.

Several very deep gravel pits
Look for intersections of major highways and the Trinity
Not unusual to find 50ft.

I know of several ponds that have 50+ feet of water. If the pond or small lake was built for flood control expect it to be super deep. All those ponds and canals down in Las Colinas and other areas were built to help flooding on the Trinity...they have to be deep or they are not doing their job of holding water.

Good to know. Thanks y'all.
The only ones I've encountered so far have been 15ft at the deepest.
I'm still learning.

They are great fun and provide good fishing in a large range of conditions.
The shallower ones with lots of vegetation fish best when we've had lots of rain.
The deeper ones fish better in drought conditions

Obviously, stay clear of them when the are flooded with strong current; they can turn into a roaring river system at times.

Long shot, but is there a website or app that tells you the depth of these?
Also, which ones are "no trespassing?" I've been kicked off some canals in Irving while bank fishing.

Navionics will show depth of water ways that are known but ponds and such aren't going to be on it. There's even a bunch of smaller public lakes that have no depth contours on Navionics. You can go to there website click on the menu bar and select chart viewer. This will start you in the Dallas area and you can curse around and zoom in to check waterways in question. The more you zoom in the more detail it will give you.

It's common if they are gravel pits. Most of the water around the Trinity in Irving is gravel pits and you would be surprised how deep some are.

Hebron and lakepointe dr in lewisville. About 30 ft deep if i remember correctly. From what i looked up, they dug out the ponds for soil to level the area for a race track. Never caught much in that pond, but caught some nice bass near by

Gravel pits hold some very deep water!