In 1928, Noel Morss was shown “irrigation ditches” along Pleasant Creek on the Dixie National Forest near Capitol Reef National Park, Utah, by a local guide who contended they were ancient. We relocated the site and mapped the route of an unusual mountain irrigation canal. We conducted excavations and employed OSL and AMS 14C showing historic irrigation, and an earlier event between AD 1460 and 1636. Geomorphic evidence indicates that the canal existed prior to this time, but we cannot date its original construction. The canal is 7.2 km long, originating at 2,450 m asl and terminating at 2,170 m asl. Less than half of the system was hand constructed. We cannot ascribe the prehistoric use-event to an archaeological culture, language, or ethnic group, but the 100+ sites nearby are largely Fremont in cultural affiliation. We also report the results of experimental modeling of the capital and maintenance costs of the system, which holds implications for irrigation north of the Colorado River and farming during the Little Ice Age. The age of the prehistoric canal is consistent with a fragmentary abandonment of farming and continuity between ancient and modern tribes in Utah.

中文翻译：

---

犹他州中部的史前灌溉：年代学、农业经济学和影响

1928 年，一名当地导游向诺埃尔·莫斯展示了犹他州圆顶礁国家公园附近迪克西国家森林宜人溪沿岸的“灌溉沟渠”，他声称这些沟渠很古老。我们重新安置了场地并绘制了一条不寻常的山区灌溉渠的路线图。我们进行了挖掘并使用 OSL 和 AMS 14C 显示了历史性的灌溉以及公元 1460 年至 1636 年之间的早期事件。地貌证据表明运河在此之前就存在，但我们无法确定其原始建造日期。运河长 7.2 公里，起点海拔 2,450 米，终点海拔 2,170 米。不到一半的系统是手工构建的。我们不能将史前使用事件归因于考古文化、语言或族群，但附近的 100 多个遗址主要是弗里蒙特的文化归属。我们还报告了系统资本和维护成本的实验建模结果，这对科罗拉多河以北的灌溉和小冰河时代的农业有影响。史前运河的时代与犹他州古代和现代部落之间农业的零碎放弃和连续性是一致的。