Dashields Primary Chamber Closure for Gate Repairs
Notice Number: 201557
Date: 12/16/2022 06:00 thru 12/19/2022 22:00
TO ALL WHOM IT MAY CONCERN:
Notice is given that the U.S. Army Corps of Engineers Pittsburgh District will be closing the 110-ft x 600-ft primary chamber to perform repairs on the miter gates. In addition, there will be a closure of the 56-ft x 360-ft auxiliary chamber to moor the USACE fleet prior to the primary chamber shutdown.
Auxiliary Chamber Closure - The 56-ft x 360-ft auxiliary chamber at Dashields L/D will be closed from 6:00 PM December 16th, 2022 through 6:00 AM December 17th, 2022.
Primary Chamber Closure - The 110-ft x 600-ft primary chamber at Dashields L/D will be closed from 06:00 AM December 17th, 2022 through 10:00 PM December 19th 2022.
DELAYS TO NAVIGATION:
The primary chamber closure is anticipated to result in delays to normal lock operations and vessel movement. During the primary chamber closure, all vessels will use the auxiliary lock chamber.
Common terms used for this notice:
Primary Vessel: The vessel that is in control of the full tow in transit before and after being broken into smaller tows (strings) for lockage.
Helper Boat: Vessel used by towing company to perform lockage when the primary tow is broken into a series of smaller tows (strings).
Pull Boat: Vessel in queue designated by USACE to pull cuts from the chamber during self-help.
Lockage String: A string of barges under the control of a vessel (helper boat). Example: A 15 barge tow can be broken into 3 strings of 5 barges.
PROCEDURES FOR AUXILIARY CHAMBER OPERATIONS:
The Corps will institute the following lockage procedure which has been developed in cooperation with the Waterway Association of Pittsburgh. Boat locking order will be determined by arrival time at Dashields L/D, and all pilots should radio Dashields L/D at normal arrival points. Red flag barges must be reported by the pilot during this radio call. All tows must be ready to lock when added to the tier sheet. No adding or swapping of barges will be allowed once the tow’s lock turn has been established. No crew changes, taking on stores etc. will be permitted during the closure. These activities will need to be arranged at landings or other approved locations and must not impede the lockage process.
Because of approach conditions (out drafts and short river guard walls), it is recommended that users limit their tow size to no more than a triple lockage. Due to the location of the tow haulage equipment and the length of the upper and lower middle walls, tow configurations of less than 50-ft in width will require self-help. Without a program of “self-help” by navigation interests, the lock can only handle up to 400 ft of tow with its tow haulage equipment.
Under normal river conditions the Lockmaster can allow a towboat to lock through with a maximum of five (5) cuts per lockage string. No building, staging, or reassembly of tows on the Lower Mooring Cell of the upper pool is permitted as the cell is out of service. While building tows coordinate with other tows in queue to avoid impedance of opposite direction of travel. This will allow a better flow of traffic and reduce delay of down bound exchange entries. By following these procedures there will be a minimal tow make-up and approach time when changing directions.
To help eliminate some of the waiting time for towboats, an arriving tow can designate to be broken up into a maximum of three (3) separate lockage strings. Each lockage string will then be locked in accordance with the procedure outlined in paragraph 2 above. The pilot of the primary vessel will have to notify Dashields L/D of the intent to break up into smaller lockage strings with a designated helper boat. Anything over 5 cuts will require a helper boat – one helper boat is acceptable. The name of the helper boat must be identified within six (6) hours of their lockage. If the designated helper boat(s) are not available when called by Dashields L/D, they will lose their turn and go to the end of the queue.
During the closure of the 110-ft x 600-ft primary lock chamber, tows should move to the closest mooring cell for staging prior to their lockage turn, rather than waiting at landings. It will be necessary for tows, under normal river conditions, to follow one another on the river guard wall when a series of lockages are being made in one direction. Each tow in the series should be aware of the tow that they follow and be on the river guard wall as soon as that tow enters the lock chamber. While this practice will speed up the lockage process, it is imperative that tows exercise extreme caution when encountering out draft or backlash conditions.
In an effort to reduce delay time at the locks, a program of “self-help” by navigation interests is necessary. A “self-help” program will allow waiting towboats to assist tows out of the lock chamber. The Lockmaster will designate the pull boats as tows arrive for position; all vessels including those with a red flag in tow can be designated as a helper boat. If a vessel refuses to be a helper boat, they must provide a replacement or go to the end of the queue. The second and third towboats in the first series of lockages in the opposite direction will be the designated pull boats. It will be necessary for all towboats to monitor their radios 24 hours a day.
Other specific procedures to facilitate lockage operations through the auxiliary lock chamber have been developed in cooperation with the towing industry. The Corps is asking for everyone’s cooperation and help in making the locking operations go as smoothly as possible during the closure of the primary chamber.
All excess rigging will be removed prior to entering the lock chamber. Remaining rigging should be ready to be knocked loose after the cut is secured in the lock chamber.
All upbound lockages will require two locking lines, one on the head and one stern and must be available on each cut. All down bound lockages will require two locking lines, one head and one stern. Each line must be at least 75 feet long and 1-1/2” in diameter. To minimize locking time, all lines will stay with each cut. Lines will not be permitted to be carried from one cut to another.
Three deckhands are required during multiple lockages.
All multiple cut tows will be made up in designated staging areas, clear of the lock gates, so as not to interfere with lockage operations.
The Dashields lock filling system may cause turbulence and surging of water while filling the auxiliary chamber. Deckhands need to be extra vigilant in tending lines to avoid an accident which could close the locks totally.
Towboats are cautioned to use minimal power when operating over the lower sill to avoid forcing debris onto the miter sill. This debris could prevent the miter gates from closing and require stoppage of navigation until the material is removed by dredging or diving operations.
If critical industrial shipments are essential to sustain continued operation, the affected companies should immediately contact the Waterways Association of Pittsburgh at least 36 hours prior to the scheduled lockage. Only the designated cargo or barges will be given priority unless stated in the request that all barges in that tow be given priority. They will review all requests for priority before submitting them to the Corps for our consideration. If it becomes necessary to prioritize lockages through the auxiliary lock chamber, the Corps will make the final decision concerning lockage procedures as conditions and situations change. In accordance with standard Corps policy, the Lockmaster may also vary the locking procedure in an effort to equalize waiting times.
Information concerning lockages will be broadcast by radio on Channel 13 and any towboat not answering a call from the locks may be dropped to the end of the waiting list.
All towboats are to stay with their tows while waiting for lockages unless designated to assist other tows through the auxiliary lock chamber.
FOR THE DISTRICT ENGINEER:
Gregory S. Turko
Deputy Chief Operations
For: Vince DeCarlo, Chief Operations