Pond Boss Forums POND CONSTRUCTION Soil questions Should I build it?

Hi:

My first time here. I'm in Austin Texas and have recently purchased a tract of land behind my home which I'd hoped would be suitable for a small pond, approx 10,000 square feet of surface area. I'm in the city limits of Austin and have a total of 7 acres and raise a few horses and would like the pond for the horses, the recreational value and the aesthetic value. In other words, I just want one cause I think it would be cool to fish in my own back yard. I had my local soil conservation guy, Eddie Garcia, come out and do an on-site visit. He'd consulted maps before coming and pronounced the site acceptable for up to 12,000 square feet and said the soil on the surface, mostly clay, looked to be suitable as well. I hired a dozer operator who was clearing the property next door and came highly recommended, to clean my fence rows and dig the pond. Initially, he was going to dig a test hole, but his backhoe was broken and he said he just knew it was going to work anyway, so he began to dig. About 5 feet, he hit a powdery white chalky soil and stopped. He told me that this 'caliche' would never hold water and I might as well stop and fill it back in. I called the soil conservation employee and asked his advice and he concurred, so we filled in the hole and resigned ourselves to not have a pond. But ever since, I've had this nagging feeling that my dozer operator and my soil conservation service worker might both be wrong. Prior to hitting the caliche, we had five feet of good clay soil, sort of a dark almost black sticky stuff which I have over most of my property and which won't grow much other than weeds and wildflowers, and I can't help but think an experienced excavator should be able to dig the clay out, dig into the caliche to the desired depth of ten feet, back fill with clay, and presto, we have a pond. But I don't want to dig a mud hole that won't hold water and will be a constant maintenance problem. So, can I have a pond or not?

Welcome, Chris.

IIRC caliche is kind of a pulverized limestone relative. We have some folks here experienced with caliche country in TX who can give you the best advice.

IMHO if you have 5 feet of decent clay over the site, you have plenty of clay to dam and seal a pond that will hold water. It will, however, take a pond builder rather than a dozer operator (the former being a specialized subset of the latter). If the dozer operator who cleared your fencerows wasn't versed in how to properly construct a sealed pond in caliche, you are ahead that he stopped before trying to learn on your nickel. As you found out, you'd be farther ahead if he'd done small test holes and found out sooner. Better you have to find a pond builder and have them put in a well built pond tomorrow than have a leaky pond today that needs fixed.

If you really "need" a pond for the horses (and that's not just one of the extremely clever excuses we pondmeisters are so adept at finding to justify our hobby that our spouses never, ever catch on), are you planning on using it for letting them swim or just for drinking water? Both uses will have impacts on pond design (swimming more so, as what I am given to understand from my wife's equine literature says you would want some very gradual slopes on the sides, at least for access points); if just for drinking water, you will want to plan fencing and plumbing so the horses don't have to drink at the pond's edge. Giving them drinking water from the pond removed from the pond field will prevent them from trashing the banks and clouding up the water.

Chris:
I have past experience in working with soils in the Austin area and would be glad to talk to you about this over the phone. Call my office at 1-800-882-3478 between 8am and noon and get Sheri to set you a phone appt. Or you can email her at mikeotto@ottosdirtservice.com
Otto