The US Army Corps of Engineers, Rock Island District (District), requests your review of the Supplemental Environmental Assessment (SEA) titled, Navigation and Ecosystem Sustainability Program Upper Mississippi River Mooring Facilities Pools 11, 14, 16, 21, and 22, dated June 2024. The District is interested in your review and comments regarding the alternative analysis and the preferred alternative for this project to fulfill the requirements of the National Environmental Policy Act.
The draft SEA is available for public review from June 26 - July 29, 2024. Comments may be submitted via email to: CEMVR_Planning@usace.army.mil, or by writing to the address below with the title of the project. For requesting hard copies, call 309-794-5319, write to the address below, or use the above email.
Address:
U.S. Army Corps of Engineers, Rock Island District
Attn: Hoffmann (PD)
Clock Tower Building
P.O. Box 2004
Rock Island, IL 61204-2004
PROJECT INFORMATION
As part of the Navigation and Ecosystem Sustainability Program (NESP), efforts are underway to reduce commercial traffic delays at Locks 7, 10, 11, 14, 15, 20, and 22 (Table 1 and Figure 1). The purpose of the project is to construct the six mooring facilities proposed in the Rock Island District in pools 11, 14, 16, 21, and 22 of the Upper Mississippi River. The project seeks to reduce commercial traffic delays by constructing mooring facilities for towboats to tie to while awaiting passage through the associated locks. Under present conditions, towboats must move in close to shore, tie to trees, ground their barges, and/or maintain engine power within these pools to hold position. With a mooring facility at the proposed locations, towboats could tie to the structures and minimize sediment re-suspension by allowing their engines to run at reduced idling speed or off. The project seeks to provide time saving infrastructure for navigation while also prevent damages caused by erosion, prop wash, and groundings of barges waiting in other areas within these pools.
Table 1. Approximate Locations of Proposed Mooring Facility Features
|
Lock & Dam
|
Mississippi River Pool
County, State
|
Upstream or Downstream of L&D
|
Mooring Facility Feature
|
Miles
From Lock Chamber
|
Approximate River Mile (RM)
|
St. Paul District
|
7
|
Pool 7
Winona County, MN
|
Upstream
|
Cell
|
1.5
|
704.35
|
Dolphin
|
1.42
|
704.25
|
10
|
Pool 10
Clayton County, IA
|
Upstream
|
Cell
|
0.38
|
615.50
|
Rock Island
District
|
11
|
Pool 11
Dubuque County, IA
|
Upstream
|
Cell
|
0.43
|
583.80
|
14
|
Pool 14
Scott County, IA
|
Upstream
|
Cell
|
4.62
|
498.00
|
Dolphin
|
4.57
|
497.95
|
14
|
Pool 14
Rock Island County, IL
|
Upstream
|
Cell
|
1.45
|
495.00
|
15
|
Pool 16
Scott County, IA
|
Downstream
|
Cell
|
0.96
|
482.00
|
20
|
Pool 21
Adams County, IL
|
Downstream
|
Cell
|
0.40
|
342.80
|
22
|
Pool 22
Ralls County, MO
|
Upstream
|
Cell
|
0.68
|
301.90
|
ALTERNATIVES CONSIDERED
1. No-Action Alternative
2. Preferred Alternative of constructing a total of six mooring facilities in pools 11, 14, 16, 21 and 22.
PREFERRED ALTERNATIVE
Construction of mooring facilities near Locks 11, 14, 15, 20, and 22 is the Preferred Alternative. Mooring facilities at these locations would allow towboats to wait farther offshore and slightly farther upstream or downstream while waiting to lock through the associated locks. These locations appear to best accommodate commercial navigation while minimizing potential adverse environmental effects within the pools in which they are located.
Construction for all six mooring facilities would occur within areas that meet the depth requirements authorized for the 9-ft Navigation Channel Project. A floating construction barge is anticipated to be used to properly facilitate construction and to stage heavy equipment and construction materials. Additionally, onshore staging areas have been identified at the associated locks. Staging area use is anticipated to be limited to vehicle parking and some material/equipment storage.
Mooring cells would not exceed 40 feet in diameter and would be made of steel sheet piling with concrete and aggregate fill. Construction of each mooring cell would vary depending on the composition of the river bottom.