Nebraska is imposing limits on the use of the Republican River this year to make sure enough water flows downstream to Kansas to satisfy a three-state agreement.

The ongoing drought forced the Nebraska Department of Natural Resources to issue an order this week requiring additional conservation measures in the river basin.

Several conservation measures have been put in place since Nebraska last used more of the Republican River’s water than it’s entitled to, but the Upper and Lower Republican River Natural Resource Districts will have to take additional steps to comply this year.

The dispute over the Republican River’s water has led to two lawsuits between Kansas and Nebraska, including one that’s pending before the U.S. Supreme Court.