McClellan–Kerr Arkansas River Navigation System

The U.S. Department of Transportation officially announced in early May 2015 that it had upgraded MKARNS from "Connector" to "Corridor" on the National Marine Highway. The announcement also added the Oklahoma Department of Transportation (ODOT) as an official sponsor. In 2015, the USACE increased its designation of the MKARNS from a moderate-use to a high-use waterway system, which means that a waterway carries more than 10 million tons per year, having a value of more than 12 million ton-miles per year. ==Construction==

The Arkansas River is very shallow through Arkansas and Oklahoma, and was naturally incapable of supporting river traffic through most of the year. To allow for navigation, construction was started in 1963 on a system of channels and locks to connect the many reservoirs along the length of the Arkansas River. The first section, running to Little Rock, Arkansas, opened on January 1, 1969. The first barge to reach the Port of Catoosa arrived in early 1971. Each lock measures wide and long, the standard size for much of the Mississippi River waterway. Standard jumbo barges, measuring 35 by , are grouped three wide by three long, with a tug at center rear, to form a barge tow that can be fit into a lock. Larger barge tows must be broken down and passed through the lock in sections, and rejoined on the opposite side. The specifications for the channel itself are: • Depth of channel: or more • Width of channel: mostly • Bridge clearance: horizontal, vertical Although Congress originally authorized USACE to dredge the channel to a depth of in 2005, it did not provide the funds to do so. ODOT says that the capacity of each barge could be increased by 200 tons for each foot of draft. ==Lock information==

The tables below list the features of the navigation system, from the Mississippi River to the origin at the Port of Catoosa. Except as noted, all locks are on the Arkansas River. No lock 11 exists; sequentially, it would have been in the middle of Lake Dardanelle. Per the animated system map (see "External links"), Dardanelle Lock and Dam (lock 10), which forms Lake Dardanelle, is the highest facility on the system (54 feet between upper and lower pools); Ozark-Jeta Taylor Lock and Dam (lock 12), just above that lake, is the third-highest (34 ft). Thus, those two facilities likely were redesigned, in terms of height and possibly location, so as to eliminate lock 11 as originally planned. The Mississippi River lock is numbered lock 99, as it was added to the system after it was completed. == 2019 Arkansas River flooding ==

Extremely heavy rains hit the Arkansas River upstream of Keystone Dam during late May and early June 2019. So much water poured into the Keystone Reservoir in a short time that it quickly became evident that a major release of water would be needed to prevent overtopping the dam, causing devastating floods downstream. Even so, water rushed downstream toward MKARNS at such a high rate that officials at USACE halted barge traffic to avoid calamities such as collisions or hitting trees and debris afloat in the river. By October, barge traffic was allowed on a limited basis. Normally, tows comprise 12 to 16 barges. However, the flood carried so much silt down river that redredging would be required to return to normal traffic patterns. In October, the tows were limited to six barges (two wide and three deep). ==Waterway traffic control==

The growth of business along MKARNS has greatly increased congestion at the locks. The Secretary of the Army has directed USACE to establish these priorities for admitting vessels to each lock: • Vessels owned by the U.S. government • Commercial passenger vessels • Commercial vessels (e.g., barges) • Rafts • Pleasure and other craft No minimum size is required for watercraft using the locks. Craft as small as canoes, dinghies, and kayaks have all been allowed to use the locks, either alone or with multiple other vessels at the same time. If commercial traffic is heavy, pleasure craft may be required to wait about 1.5 hours or may be allowed to lock through with commercial vessels. ==See also==