Lock Performance By Wesley W. Wilson University of Oregon and IWR
Purpose of Study The inland waterway consists of the river and a series of locks and dams that allow the river to be navigated. The capacity and use of the waterway depends on lock performance. There is a wealth of information on locks and lock performance which can be used to estimate the effects of particular lock characteristics on performance. Purpose To develop and estimate a model of lock performance as a function of lock and flotilla characteristics.
Locks Locks: Necessary to make the river navigatable. River Lock River Pool 1 Pool 2
Flotillas and Lockages A flotilla consists of a power vessel and a set of barges which have different configurations and dimensions. Locks have a fixed set of dimensions. Single Lockage: Flotilla can pass through in one cut. Double Lockage: Flotilla must take two cuts to pass through the lock.
Single Lockage Approach the lock Enter the chamber Gates close Lock is filled (or emptied) Open gates Exit the lock.
Double Lockage Approach the lock Enter the chamber Uncouple and back out second cut (*) Close gates Fill (empty) the lock chamber Open gates First cut exits (*) Close gates (*) Fill (empty) the lock chamber (*) Open gates (*) Second cut enters lock chamber (*) Close gates (*) Fill (empty) the lock chamber (*) Open gates (*) Recouple the tow (*) Exit
Lock Characteristics Age Dimensions (length and width) Gate Types Number of chambers Lift
Upper Miss Locks Age 29 Locks Year opened ranges from 1922 – 1990
Lock Length
Lock Dimensions Standard Lock on UMISS is 110 by 600. _______________________________________________ Width Length56110Total Total32629
Lift LiftFreq.Percent Total
Flotilla Characteristics Flotilla is a tow-barge configuration that passes through a lock. In 2000, there were about 69,989 flotillas on the UMiss that were used in the analysis.
Flotilla Data Over 69,000 observations (flotillas are tow/barge passages through a lock) Characteristics: Number of barges per flotilla:
Flotilla Data Flotilla Lengths
Flotilla Width
Flotilla Draft
Characteristics Number of cuts 1-33,945 (48.5%) 2-36,043 (51.5%) Up and Down River Cuts 35,319 Down River 34,670 Up River Day versus Night 38,481 (55%) Day
Cuts and Month
Lockage Types TYPENumberPercent C - Consecutive 35, J - Jackknife 9 0 K -Knockout 6,231 9 S - Straight 26, T -Barge Transfer 68 0 V - Set over 1,224 2 Z -Other 3 0
Mechanical Assist Type Number Percent I - Tow with Bow Thrusters 70 0 J - Tow haulage (e.g., winch) (e.g., winch, kevel) K – Hydraulic N – Tow and Barge equip (e.g., winch, kevel) None
Processing Time (End of lockage-Start of Lockage-Stoppage) Mean77 minutes 50% 79 minutes
Lock Length and Processing Time
Lock Times-Size and Cuts LockMinutes AllSingle Multiple All
Econometric Model Time = f(Lock, Flotilla, Vessel, Passage, Time of day) Lock: Dummies for width and length Lift Age Flotilla: Length, width, number of barges Vessel:Horse power and dummy for tugboat or not. Passage:Dummies for single or double cuts Dummy for first in queue or not Time of day:Dummy for night or day. Unobserved factors: River conditions, lockmaster rules.
Results-Lock Types (R 2 =83) Lock (600 by 110 base) 1200 by by by log_lift log_age
Flotilla Effects log-length log_width log_area/NUMBAR
Vessel Effects v_hp v_length v_brea~h v_age v_draft tugboat
Passage Results mult daytime q_ upriver