Classification
- Incident Type: Tow capsize
- Severity: High
- Evidence: The Transportation Safety Board of Canada confirmed the occurrence and later reporting describes the sequence and safety findings; no final public report was located.
Vessel Details
| Field | Value |
|---|---|
| Vessel Name | Lac Manitoba |
| Vessel Type | Tug |
| Flag State | Canada [CA] |
| IMO Number | |
| Official Number | 169953 |
| Gross Tonnage | |
| LOA (m) | 18.56 |
| Breadth (m) | 5.06 |
| Bollard Pull (t) | |
| Power (kW) | 746 |
| Owner/Operator | Nadro Marine Services |
| TEU | |
| Year Built | 1944 |
| Crew Size |
Incident Details
| Field | Value |
|---|---|
| Date | 2015-06-22 |
| Location | St Lawrence near Cornwall |
| Coordinates | 45.0200, -74.7300 |
| Region | Canada |
| Fatalities | 0 |
| Injuries | |
| Missing | |
| Cargo Loss | |
| Direct Damage | |
| Economic Damage | |
| Insured Loss | |
| Salvage/Cleanup Cost |
Key facts
- Lac Manitoba capsized and sank after becoming pinned against the work barge OC 181 in the St Lawrence current.
- The public account identifies three people as escaping from Lac Manitoba; the one reported injury was not assigned to a named tug.
- A separate capsize involving LCM 131 occurred about five hours later during the same bridge-work operation.
- TSB investigators later reported current speeds of 5.6 to 7.4 knots and said the suitability of the tugs for the river conditions had not been thoroughly assessed.
- Vessel-history reporting states that Lac Manitoba was later raised, rebuilt, and returned to service as Burch Nash; a total-loss designation is therefore not established.
Narrative
On 22 June 2015, Lac Manitoba was assisting with positioning the 178-foot steel work barge OC 181 near a footing of the Seaway International Bridge at Cornwall. LCM 131 was also involved in the operation, but the Transportation Safety Board of Canada treated the two tug capsizes as separate occurrences and said it was not known whether they were related.
According to the later account of TSB investigators, Lac Manitoba was upstream of OC 181 and helping hold the barge in position. The tug lost power, drifted downriver, and collided with the barge. The current then pinned the tug against the barge, causing it to list, downflood, heel over, and sink. The crew abandoned into a life raft. Contemporary local reporting said three people escaped from Lac Manitoba and that the tug crews were accounted for. The same report described one non-life-threatening injury among the people rescued from the combined scene, but did not identify the injured person's tug.
Professional Mariner reported that current speeds ranged from 5.6 to 7.4 knots while an upstream dam was releasing water. It also reported that TSB investigators had concluded the operation's tug suitability and risk assessment had not been thoroughly considered. Those causal details are reported findings from the later article, not a final public TSB report located in this review. Vessel-history reporting records that Lac Manitoba was subsequently raised and rebuilt, so the sinking did not establish a permanent total loss.
Sequence of events
| Date/time | Event |
|---|---|
| 2015-06-19 | TSB investigators later reported that an earlier attempt to move OC 181 with Lac Manitoba alone had been overpowered by the current. |
| 2015-06-22 16:00 local | Lac Manitoba was assisting OC 181 near the Seaway International Bridge, lost power, drifted downriver, and became pinned against the barge. |
| 2015-06-22 | Lac Manitoba listed, downflooded, heeled over, and sank; its crew abandoned into a life raft. |
| 2015-06-22 21:00 local | A separate occurrence involving LCM 131 took place during the same operation. |
| 2015-06-23 | The TSB announced that it was deploying investigators to assess the Lac Manitoba and LCM 131 occurrences. |
Contributing factors
| Factor | Evidence status | Description |
|---|---|---|
| Strong river current | Reported | TSB information cited by Professional Mariner put the current at 5.6 to 7.4 knots while the upstream dam was releasing water. |
| Loss of power | Reported | Professional Mariner reported the TSB investigator's account that Lac Manitoba lost power before drifting into the barge; the operator separately attributed the loss of power to a fouled port propeller. |
| Tug suitability and risk assessment | Reported | Professional Mariner reported the TSB safety letter's conclusion that the suitability of the tugs for the river conditions had not been thoroughly assessed. |
Investigation
The TSB announced on 23 June 2015 that it was deploying a team to assess the capsizes of Lac Manitoba and LCM 131. Professional Mariner later reported that the TSB sent a marine safety information letter to the operators and contractors on 28 August 2015. No final public TSB investigation report was identified. The later causal account is therefore retained as reported rather than presented as a confirmed final finding.
References
- TSB media advisory on the Lac Manitoba and LCM 131 occurrences
- Tugs capsized because they were too weak for the task, TSB says
- Video: Two tugboats capsize on river, crews safe despite an injury
- Two tugs sink on St. Lawrence River near Cornwall
- Burch Nash: Lac Manitoba vessel history