Managing flooded grain bins

The rate of spoilage for wet grain depends on its moisture content and temperature.

Grain that was submerged for more than a few days will have a moisture content of about 30 to 50 percent. At warm spring and summer temperatures, grain this wet will become moldy in a few days.

If the bin was only partly submerged, many crop producers wonder if they can leave dry grain on top of the wet grain.

What to do

While dry grain will be relatively safe for a few weeks, it’s best to separate it from the wet grain as soon as you can. This is because the wet grain will begin to spoil in a few days and generate mold, heat and odors that could reduce the quality of the dry grain above it.

Try to unload the dry grain without mixing it with the wet. A vacuum-type grain conveyor that sucks the dry grain out the top of the bin might be the best way to do this.

Then, consider:

• Selling the dry grain.

• Moving it to an undamaged storage bin at your place or a neighbor’s.

• Temporarily storing it in a machine shed or other building modified for grain storage.

If the grain isn’t contaminated with excessive silt, bacteria, fuel or chemicals (grain that’s in contact with flood water is likely to be contaminated), it might be possible for you or a neighbor to feed wet grain directly to livestock. However, check the regulations first.

Remember that wet grain will spoil quickly. If you can't feed it in a few days, consider adding a grain preservative to extend shelf life.

Store the grain

If the grain moisture is between 25 and 35 percent, consider ensiling it in an upright silo, plastic-covered horizontal silo or plastic silage bag.

Be aware that grain in ruptured bins could contain bolts, bin hardware or other debris that should be separated out before the grain is fed. Consider using grain cleaners and/or magnets for this.

Dry the grain

Another option is to dry the wet grain in a gas-fired dryer. Energy costs for on-farm drying will be high. Be aware that after drying, grain should be cooled to less than 60 degrees Fahrenheit for safe storage. It's unlikely that weather in the summer months will be cool enough to adequately cool grain that’s dried during summer months.

If you can remove the dry grain from the top of the bin and get the fan going, you might be able to use unheated air to dry wet grain in bins equipped with fully perforated floors and large drying fans.

Your chances of success with unheated air drying decrease as grain moisture, outside temperature and grain depth increase. If the grain is much wetter than 20 percent moisture, don't use this drying method for more than about six feet of grain.

Molds and toxins

Under certain conditions, grain molds can produce mycotoxins that can cause animal feed refusal, health problems or even death. Beef cattle (except for breeding stock) are somewhat less sensitive to molds and mycotoxins than other animals, so feeding suspect grain to beef cattle as part of a mixed ration would be safer than feeding it to other animals.

If grain develops a lot of visible mold, test for mycotoxins before feeding it or spending money to dry it. You should probably discard grain that’s badly damaged by mold or has high levels of mycotoxins or contaminants.

You probably won’t be able to remove grain through the bin’s unloading system.

If electric motors on the unloading system have been underwater, it’s best not to start them until they’ve been cleaned, dried and lubricated. Very wet grain probably won't flow out of the bottom-unloading sump anyway. Consider using a vacuum-type grain conveyor to suck the grain out of the top of the bin.

If the water line was below the level of the bin’s side door, it might also be possible to insert an auger into the dry grain through a small opening in the side door. However, make sure the auger extends to near the bin’s center. Unloading a bin from one side creates uneven sidewall pressures that can damage the bin.

Structural damage

It’s not unusual to find structural damage to bins after floods. Because grain swells when it absorbs moisture, it exerts a great deal of pressure on the inside of bin walls. This often results in stretched bolt holes, broken bolts and torn bin sheets.

Sometimes, bins are knocked off their foundations or dented by the pressure of moving water or the impact of floating debris. Rapidly moving water can also cause erosion around foundations.

Equipment damage

Drying, aeration and unloading equipment on bins will likely be inoperable immediately after floods. However, in many cases, electric motors and controls and gas burners will work again after they’re cleaned and dried.

Don't try to start electric motors until they’ve been cleaned and dried or they might burn out. You should also clean mud and debris off the fan blades to prevent imbalances that might lead to bearing damage. Bearings might need to be dried, relubricated or replaced.

Duct damage

In many cases, aeration ducts and areas under fully perforated floors will contain mud and saturated grain fines. Clean these areas before refilling the bin.

Repairs

Companies that work on grain bins are likely to be quite busy after widespread flooding. If you need repair work, try to line up a contractor as soon as possible to repair your bins before harvest.

If water surrounded the bin foundation but didn't actually flow into the grains, the grain is probably fine as long as:

• The bin has an elevated, fully perforated floor.

• The water level remained below the floor.

What to do

You might still need to check for:

• Erosion around the foundation.

• Damage to the fan and unloading system.

• Mud accumulation under the floor, such as in the in-floor aeration ducts.

• Damage to grain that rests directly on a concrete floor. It’s possible that water has moved up through small cracks and pores and wet a few inches of grain next to the floor.

If you can get the aeration system to work, try to dry the wet grain layer by aerating it. Or, if you can get the unloading system to work, consider transferring grain from one bin to another to get the layer of wet grain off the floor before it molds.