After comparing the economics of bunker silos to upright silos, brothers Rick and Norm Atwater of Barker, N.Y., decided to stick with upright silos. But the new silo they put up is unlike any you've ever seen before.

The 100-ft. tall, 30-ft. dia. poured concrete structure has a 12-ft. high drive-through alley underneath it for fast and easy unloading. As far as they know, the Atwaters say the new-style silo is the first of its kind.

Their new silo was built by Sollenberger Silos Inc.

Here are a few of the engineering innovations that went into the silo. Twelve 18-in. dia. columns, each containing 1 cu. yd. of poured concrete, run along each wall of the drive-through. They support the floor of the silo which is made of 15-in. thick reinforced concrete.

The silo is equipped with a Big Jim unloader from J-Star that unloads down a 19-in. flue at center which is formed when filling the silo. The Atwaters pull their 9,000-lb. capacity Knight Reel Auggie 3450 TMR mixer into the silo and drop 700 to 800 lbs. of haylage per minute into it using a remote control that activates the unloader.

"It's 'push button' farming that's as convenient and accurate as it gets. That's important when you're mixing up to eight batches and making eight trips through it a day," Atwater says. "All you do is push the on button, set the mixer scales, and push the off button just before you're at the desired weight. There's absolutely no guessing as there would be if you were loading the mixer with a payloader out of a bunker silo."

By reducing spoilage and the labor to fill, pack and unload bunk silos, the Atwaters and Sollenberger Silos agree the big silo is more cost-effective in the long run.

Atwater says the silo itself is working out beautifully but that there have been a few operational and breakage problems with the unloader.

"There are few problems unloading, but it doesn't keep up very well when filling the silo," he says. "This unloader would probably work better with a 20 or 24-ft. dia. structure."

The Atwaters may put up another drive through silo if they expand from 300 to 400 Holsteins as planned, he adds.