Ag Weather Forum

During a phone interview for this week's spring weather forecast series, Nebraska state climatologist Al Dutcher shared some concerns about irrigation supplies for the 2013 season. These details will not make it into the series—or if they do, there will be strict editing for copy limits. But this is good information nonetheless.

In Al's view—"It's difficult for people to understand that (irrigation supplies) have two battles--short term and long term. Where we may wind up having problems is if central Rockies snow pack doesn't improve in the next 30-40 days, leading to poor inflows."

Here are Al's thoughts on irrigation prospects for this season in Nebraska.

1) Gravity irrigation—where the water runs from one end of the field to the other in between corn rows—is tougher with dry soils. Twenty percent of the irrigation in Nebraska is gravity irrigation.

2) Water allocations for irrigation are declining. The big Central Nebraska Public Power and Irrigation District dropped its allocations to 10 inches for the year—and if the central Rockies snow pack is bad—it may have to revisit that and cut back even more to just eight inches.

3) Junior water right irrigators had problems last summer in the Republican, Blue and Elkhorn basins. Those problems may start earlier this year. Junior water rights holders face earlier restrictions this year—which means that people who weren't affected last year could be affected this year too.

4) A lot of problems were reported in northeastern Nebraska with wells pumping air last year. Since October 11—precipitation shortages approaching 17 inches have accrued. "They're going to have to have rain in incredible amount in the next few months for that to offset the problem arising even earlier," Dutcher said.

How badly can water shortages affect yield? Dutcher told me that in Saunders county, Nebraska (just west of Omaha about 30-40 miles)—producers who started to have problems applying water in mid-August last year had an average 40-50 bushel per acre reduction in yield compared with those who were able to irrigate all the way to black layer. So, a field capable of 225 bushels per acre dropped to 175 bu/A. And, this year those problems would develop earlier than mi-August.

5) There is a risk going forward regarding electricity for running irrigation pumps. Last year, growers mostly turned their pivots on and didn't stop—which at times overloaded the power grid. "There was a price paid in sandier soils with brownout issues," Dutcher said.

Nebraska Public Power District has already allocated 3-4 generators in north-central and northeast Nebraska to meet that additional demand. It's needed, because in an area from Norfolk, Nebraska southwest to Broken Bow, Nebraska there has been another three-inch precipitation deficit since October 1, 2012. Some of this power supply issue is growers switching from natural gas or diesel motors to electricity. But, drought made its presence known as well.

Why does this make a difference? Well, Nebraska ranked #3 in corn production in 2012. Problems with water supply in 2013 could translate into the possibility of lower production in this part of the Corn Belt.

Bryce

Twitter @BAndersonDTN

(ES)

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