This week at a production system’s grower meetings, I always asked for a show of hands on who had full pits. At every location, hands went up.

It’s only the middle of September, and we are dealing with full pits. In reality, this only represents about 10 months of production since many pits didn’t get pumped last fall until November.

Blame the full pits on last year’s corn crop quality.

In barns with wet/dry feeders or bowl drinkers, grow-finish pigs have a water to feed ratio of approximately 2 lb of water per pound of feed. This means that total drinking water disappearance is 2 pounds for every pound of feed. With a density of 8.3 pounds per gallon, this means the pig uses 0.24 gallons of water for every pound of feed. Barns with nipple drinkers often have water:feed ratios of 2.7 to 1, resulting in 0.33 gallons of water for every pound of feed.

In my last blog, I commented on the poorer feed conversion this year in production systems because of the poor quality of the 2009 corn crop. If the conversion is 0.2 units worse this year than last due to corn quality, this is an extra 44 pounds of feed to grow a pig from 55 lb to 275 lb. This extra 44 lb of feed meant the pig needed an extra 10.6 gallon of water for its growth if the barn was equipped with wet/dry feeders or bowl drinkers. This translates into an extra 10.6 gallon of liquid in the pit for every pig grown to slaughter weight.

For a 1200 head grow-finish room with 2.8 groups of pigs per year, this translates into over 35,000 more gallons of manure. This is almost a 10% increase in manure volume. This 10% increase is just enough to have growers report full pits in 10-11 months, versus the full year storage they have come to expect.

For facilities with nipple drinkers, the increase in manure volume is even more dramatic – over 50,000 more gallons of manure in a production year.

Many of these growers will be pumping pits in coming weeks. Next year, if we have a wet fall and late harvest such as 2009, it may mean that we should be planning on 13 or 14 months of storage between pumping events.

Based on the above math, it looks like producers should plan on a second pumping event just prior to freeze up, or a pumping event next spring if they want to avoid full pits in late August or early September.