Information included in the below public notice, which was published Aug 28, included a presentation with incorrect information. The information is in the summary of the article.
The video of the presentation was updated and provides corrected information. The public notice remains the same.
The Tulsa District, U.S. Army Corps of Engineers, is soliciting comments from the public and agencies on the potential effects of the emergency dredging and placement of dredged spoils activity that occurred during the spring and summer of 2019, as well as, the effects of the water drawdown, impact to the mussel population that was affected as a result of the drawdown, and mitigation efforts, on the Arkansas River, southeast of Tulsa, Oklahoma.
The Corps has initiated an after action Environmental Assessment (EA) for this activity that occurred in the Webbers Pool and Robert S. Kerr Pool in Oklahoma. The EA for this after action is authorized in Section 216 of the River and Harbor Flood Control Act of 1970 and Section 1202 of the Water Infrastructure Improvements for the Nation Act of 2016. The EA will assess how the action affected the human environment and to make the determination if the action was compliant with the National Environmental Policy Act (NEPA). Your comments will help the Corps in development of this EA.
In May and June 2019 record rainfall fell in Southeastern Kansas and Northeastern Oklahoma which caused widespread flooding in the region. Approximately 15 Corps of Engineers reservoirs in the Upper Arkansas River Basin, Verdigris River Basin, and Grand (Neosho) River Basin, all within Tulsa District, flood pools were flooded to the top of their capacity. With so many reservoirs at the top of their flood pool capacity, the Tulsa District managed reservoir releases so there was a balanced approach to evacuating flood waters from all pools. Unfortunately, significant and in some cases, catastrophic flooding was unavoidable due to the received rainfall. River flows, measured in cubic feet per second (CFS), were overwhelming within large portions of the river system. Below Keystone Dam just west of Tulsa, the rate of river flow approached 300,000 CFS at its maximum volume and was flowing at 600,000 CFS at W.D. Mayo Dam Lock and Dam 14.
The McLellan-Kerr Arkansas River Navigation System (MKARNS) just downstream from the Arkansas River confluence with the Verdigris River and the Grand (Neosho) River had a sustained volume of well over 600,000 CFS over a duration of more than a week. This increased river flow was carrying an enormous volume of sediment which was transported from the three upstream feeder river basins and was passed through upstream dams and into the Navigation System, where much of it was subsequently deposited. Result of this increased sedimentation was 3 miles of river channel was clogged with an estimated 1,000,000 cubic yards of sediment. This material had to be removed before the Navigation System could be reopened for navigable traffic and interstate commerce. Therefore, the Tulsa District made the decision to commence dredging and dredge spoil operations prior to NEPA review so economic impacts to the region would be reduced.
There was another complicating factor other than three miles of river channel being clogged with sedimentation. On May 23, 2019 two fully-loaded barges moored in the Muskogee area tore loose and were carried downstream, where they collided with the dam at Webbers Falls and sunk. The barges were forced against three of the structure's open gates. The two sunken barges impeded the operation of the gates and those gates could not be closed, resulting in the drawdown of the pools and subsequent negative impacts to mussel populations. Removal of these barges was dependent on the emergency dredging action, specifically the portion within the Robert S. Kerr pool. The salvage crew hired for this task utilized a tow barge which the only feasible means of travel was up the McLellan-Kerr Arkansas River Navigation System to the Webber Falls Lock and Dam.
Pursuant to Section 102 of the NEPA as implemented by the regulations promulgated by the Council on Environmental Quality (40 Code of Federal Regulations Parts 1500-1508 and U.S. Army Corps of Engineers’ Engineering Regulation 200-2-2), an Environmental Assessment will be conducted to ensure compliance with the NEPA and appropriate environmental laws, regulations, agency policies and guidance, and executive orders, and to provide any necessary mitigation as a result of impacts from the emergency dredging, discharge of dredged material, and draw down of the pool.
Our office would like to solicit any input you may have with respect to this after action environmental assessment for the Webbers Pool and Robert S. Kerr Pool Emergency Dredging and Placement to assist us as we progress through the NEPA process. A brief presentation regarding this action is available starting on August 20, 2020, on the Tulsa District website: www.swt.usace.army.mil.
We look forward to receiving your written comments, which are due by September 20, 2020. Please contact Mr. Jeff Knack, Chief, Natural Resources and Recreation Branch, Tulsa District, by mail U.S. Army Corps of Engineers, 2488 E 81st Street, Tulsa, Oklahoma 74137-4290, email at jeff.knack@usace.army.mil, or telephone at (918) 669-7660 with comments, questions, or the need for further information.