|It looks messy, but this fenced water gap remains in place despite several high-water events. Tree limbs and debris pass under the tin, which swings up during high water.
Despite all you may do to build a water gap that holds, Mother Nature can show you it's only as permanent as the next big rain.
Jeff Pollard, a fence builder and cattleman near Woodburn, Iowa, has learned from his own farm that the best water gap is one that lets the water flow and allows debris carried by the water to move freely through a water gap structure.
Pollard started building fences in 1986 and is booked ahead for more than a year. He uses different types of fencing materials and structures for water gaps on the 1,600 acres he farms, depending on the amount of water flowing through the fence area.
First, Pollard tries to eliminate the need for a water gap. Pollard is a good land steward on his crop acres and is now focusing his efforts on improving his pastures. To remove ditches in pastures, land is reshaped using dry fill dams to stop soil and water erosion.
In one pasture, he repaired an erosive ditch by regrading the steep hillside and installing a tube with dry fill. On top of the wide tube crossing, he built a boundary fence. With the hillside regrading and tube crossing, Pollard avoided fencing a water gap and reduced erosion.
When he must fence a water gap, Pollard often uses a solid barrier rather than open wire. For medium-sized creeks, he hangs a cable from posts on both sides of the creek. About a foot below the cable, he hangs pieces of tin with baling wire.
"Solid tin panels work better than any other type of fencing because nothing collects in the tin. The panels just swing up during high water,” Pollard explains.
|The type of water gap Jeff Pollard of Woodburn, Iowa, builds depends on the amount of water that will flow through the fence.
For larger creeks or small rivers, he uses a single strand of electric poly wire fencing that easily breaks when water levels swell. The poly wire is attached to fence posts on the creek banks with bungee straps for easy release.
"Replacing a single poly wire is a fast and easy repair that my wife or girls can do. Plus, a temporary water gap is the most economical and practical solution for high-volume waterways,” Pollard says.
Nick Morrell, Natural Resources Conservation Service district conservationist for Warren County, Iowa, agrees that "breakaway” fencing is often the best option for areas with high-water flows.
"Each site is different; some will wash out every time and others won't. One way to fence a water gap is with a strand of electric wire strung across a creek and attached to posts on top of the creek bank,” he says.
From the single wire, attach a second wire with hanging poly strands tied to ½" nuts to help the strands hang straight. Place strands 12" to 18" above the normal water flow, Morrell says.
"Attach a floodgate controller to the secondary electric wire so that as the water rises and touches the poly strands, the circuit for that section of fence will shut off when it starts drawing too much electricity. After the water recedes, the controller will turn the current back on,” Morrell says.
Another option is breakaway gates that open in high water. From a corner post on one side of the creek, a gate made of fencing or other material is attached by lightweight wire to the opposite corner post. During high water, the gate swings open. The gate remains intact, can be pulled from the sand and debris when water recedes and then reattached. BT