LINCOLN, Neb. — Underground water tables declined in 90 of Nebraska's 93 counties between spring 2012 and spring 2013, an "unprecedented" drop, according to an article on Omaha.com.

Aquifers dropped an average of 2.5 feet as farmers pumped more water for irrigation during 2012's record heat and drought, reported the article.

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"An average one-year decline of this magnitude has never been recorded before in the state,” said Aaron Young, groundwater resources coordinator for the University of Nebraska-Lincoln.

Groundwater monitoring has been recorded in the state since 1930, noted the article, and groundwater levels typically decline in dry years and recharge in wet years.

Flow monitoring and pumping limits will be imposed in most areas during the irrigation season this year if the water table drops, according to the article.

Read the full article here.