From The Lamar Ledger:
Because of the water allocation systems in play in Colorado, due to the Arkansas River Compact between Colorado and Kansas, rights to utilize the water in the river are broken into senior and junior water rights, with earlier, or senior claims to water use from the river taking precedence. The River Call states the date of the most junior or recent claim for water use that is eligible to receive water. For example, if the date of the River Call is 3-10, 1889, then those with water rights dating to March 10, 1889 are able to divert water for [beneficial] use.
In 1902, Kansas claimed that Colorado was taking too much of the water from the Arkansas River, making the land dependent on the river in Kansas less valuable. The Supreme Court dismissed Kansas’ petition in 1907 on other grounds, finding that development of land in Colorado had depleted the water in Kansas. The Court invited Kansas to file a new claim if the situation worsened. In 1943, The Supreme Court restrained further prosecution of Colorado by Kansas against Colorado users of the Arkansas River. A settlement was negotiated in 1995 between Colorado and Kansas, creating the Arkansas River Compact and in 2001 a special master ordered Colorado to pay damages to Kansas for use of water in excess of what it was entitled to have from 1969 on. Several ditches in Colorado and Kansas utilize the water. There are six ditches in Kansas, including the Amazon and Farmer’s Ditch. Ditches in Colorado include the Bessemer, Highline, Rocky Ford, Catlin and Amity.
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