When the Whittle family in Volga, Iowa, began contemplating a switch to sand bedding, they knew their manure-handling system would also need an overhaul to make it an optimal change. The end result incorporated sand settling lanes and weep cells, something they had never seen done before.

Whittle Farms is a 500-cow family dairy farm. It is owned and operated by Tom and Cheryl Whittle and their children: Mike and his wife, Hollie; Deb and her husband, Lanny Deitchler; and Pat.

“We were looking for cow comfort,” Mike Whittle says. The cement was 10 years old and the cows needed better footing. Plus, the mattresses in the stalls were showing their age. He had heard of the many benefits to sand, but also knew they couldn’t afford to store it in their manure lagoon or haul it to their fields, some of which are 10 miles away from the farm.

The Whittles figured it would take 90 tons of sand a week to bed their 540 cows, plus dry cows and some heifers. That’s a lot of money if left unclaimed. Mike also adds that sand has a tendency to wear things out, and they preferred to have it settle naturally.

Like most dairymen, they began to research their options. They found a lot of weep systems in Minnesota, but the Whittles also needed a way to reclaim the sand. They saw sand settling lanes, but couldn’t find anyone who had intertwined the two.


Needing additional help, they turned to Dr. Joe Harner at Kansas State University. He analyzed their plan and helped set the slopes and pitches so everything could flow by gravity alone.


Once the design was set, they tore out their old stalls, removed the mattresses and cement and replaced them with sand. Pre-cast walls were added to the collection pits under the barn, along with a two-foot tube for the flume.

Now manure is scraped to the collection pits, where water from the lagoon is pumped to wash the flume. The water and manure flow down a 250-foot sand separating lane, where the sand stays behind. The rest flows into one of two weep cells, measuring 200-feet long by 40-feet wide.

The solids collect in the weep cells, and the liquids weep through a wall built of hog flooring into a central lane. That lane leads to the lagoon, and the process starts all over again. Each spring and fall they empty all but 18 inches from the lagoon. That amount is needed to keep the flush system operating.

“It’s working so far,” Mike says. “We’re still working out the bugs with the weeping water.”

He adds they are considering installing a 5/8-inch weep wall instead of a 3/8-inch wall to allow even more water to seep through. The walls are also scrubbed every time solids are hauled to keep any material from building up and blocking the flow of liquids.

One big drawback to this system is that a 1/2-inch of rain can equal one inch in the lagoon, Mike says, simply because the surface area is so much greater than it was before.

When it comes to the sand settling lanes, “we’re still learning the curves,” Mike says.

Sand that settles in the lanes is collected twice a day and placed on the cement beach to dry in the sun. It will sit for four to six months before it is used again for bedding.

When they first started flushing, the Whittles learned the importance of clean liquids to wash the sand. Mike relates that they hadn’t cleaned the lagoon out enough so dirty water was being used to wash the sand, and it wasn’t turning out like they had hoped. So they tried again. They cleaned the lagoon again, and this time received a permit to pump in some water from a nearby river to begin the flush cycle with cleaner liquids.

He says this past winter they didn’t have any trouble with the flow of the system. However, the previous winter when temperatures dropped below 40˚F, the sand lanes did freeze.

The reclaimed sand is unusable during the winter months. Once placed on the beach, it freezes together before it can dry. The Whittles have adapted to this and purchase new sand for those months. The reclaimed sand is hauled to a separate pile for use as heifer bedding in the summer.

With the right type of sand, Mike figures they are re-claiming 80 to 85 percent of what went in the barn. Initially they used the sand that was dug out from the area where the lanes were built. They’ve also tried silica sand, but lost too much of it into the lagoon. Washed mason sand was used too, but it was leaving too coarse of rocks in the stall.

The system is meeting the Whittles’ goals – to keep the sand and solids out of their lagoon. It has also resulted in lower somatic cell counts and increased cow numbers.

“This new system has gained us some extra nutrient storage space,” Mike says. “We’ve been pushing up the numbers.” PD

PHOTO 1: Mike Whittle stands in front of the two 200-by-40-foot weep cells that were added to strain solids from the nutrient management system at his family’s dairy. Liquid weeps through hog flooring walls into the center alley. It then flows into the existing lagoon.

PHOTO 2: Sand is collected twice a day from the sand settling lane on the right. It is piled on the concrete beach to dry in the sun. Photos by Karen Lee.

Karen Lee