Tips for Building a Farm Pond
By Burt Carey
Growing up in rural Northern California, my two brothers and I were blessed to have a down-the-road neighbor who allowed us to fish in his farm pond just about anytime we wanted. It came to be known to us as Jack’s Lake.
The pond sat across a fallow cattle pasture at the bottom of a natural gully that collected rainwater 
from hundreds of surrounding acres. Jack’s Lake stretched nearly a quarter-mile north to south and was about 150 yards wide across its widest span. Its upper half was shallow and teeming with water grass. Trees lined its shoreline. The dam at the south end was braced by a row of trees whose water-bound roots and crooked branches provided habitat for various fish species, songbirds, waterfowl, frogs and more.
We spent endless hours catching its bounty of largemouth bass, bluegill, channel catfish and bullfrogs from a homemade boat with 6-inch aluminum pontoons that made the craft sturdy and kept it afloat. Paddles were our only mode of power. Mom never had to worry where we would be, and she could catch occasional glimpses of us out the east-facing picture window of our house.
Years after I had left home, our neighbor sold the lake and his property, pocketing a sum unknown to me but surely significantly higher than the price he paid for it in the 1960s.
Aesthetically, a farm pond can be the biggest enhancement a landowner can build. Financially, a properly built pond will increase the value of a property when it comes time to sell. And most people who opt for living in the country at some time or another will make a decision to build one or not. Here are some things to consider.
Let’s start with the big picture: What would be your pond’s purpose?
Few farm ponds are mere pools of water that collect in a low spot. In short, ponds are there for one or more reasons. Will it be used to provide water for cattle or other livestock? Perhaps you just want a small fishing pond. Or will it be for aesthetic purposes only, something to look at from your front porch?
Once you’ve decided what you want a pond for, you’ll have several things to consider, such as location, water sources, size, structure, drainage, emergency spillways, and perhaps the biggest potential hurdle, legality.
State resources agencies can guide you and help walk through whatever permitting process might need to be negotiated. If you have neighbors who share a creek, for example, their short- and long-term interests in that water flow could be impacted by a pond. Not all waterways fall under federal jurisdiction but very well may be controlled by one or more state agencies.
Your geographic location and water source (a spring, surface runoff, stream or well) will dictate the size and depth of your pond. Ponds in wet and humid regions – the East, South and Pacific Northwest – can be as shallow as 5 to 7 feet deep. In arid regions such as the West and Southwest, the minimum recommended depth is 8 to 14 feet.
The size of a watershed drainage area surrounding a pond fed by surface runoff is critical. Filling a one-acre pond with 5 feet of water in a wet, humid area might require a watershed as small as 15 acres. That same size pond in an arid location could require up to 500 acres of watershed drainage.
Actually constructing your pond might sound exciting and enticing. Here’s a word of caution: Don’t do it. Unless you have the proper training, this is where it’s best to hire a professional. You’ll have to conduct soil tests, build a dam that can withstand floods, earthquakes and other calamities, and install drainage and overflow outlets. Depending on the stream bed, you might also be required to fortify the spillage area with riprap or other materials to prevent soil erosion.
Keeping the law of gravity in mind, water always flows to the lowest elevation. This is most likely your starting point. A dam will have to be constructed, beginning at the bedrock level and preferably a location with a natural clay material. Dams on farm ponds are typically up to 10 times wider at the bottom than the top, and constructed of a clay core surrounded on both sides by a non-porous earth material.
You’ll also need to know what types of plants are good or bad for your pond, and how to control their growth through the use of fertilizers and chemicals or with fish species. Plants also act as natural means of soil erosion, which will help extend the life of your pond. Most ponds, regardless of erosion-control methods, require occasional dredging roughly every 20 to 30 years.
Whether your pond is a half-acre or bigger than 20 acres, it will become home to fish and other wild creatures. The best part is that you get to pick which species inhabit your water. Check with your local office of a state fish and wildlife agency if you aren’t sure what types of fish to plant. Commercial fish growers can sell seed stock and make recommendations for ratios of forage fish to sport fish, and the best ways to maintain proper ratios for healthy fish populations.
Once built, your pond will become a centerpiece of your property that will be enjoyed for generations.
Source: Baret News
