US Coast Guard, TSAC urge action on overhead clearance casualties


Casualties involving cargoes striking overhead bridges or power lines are among the maritime industry’s most preventable, and the U.S. Coast Guard is taking steps to ensure that crews understand the simple steps needed to ensure safe transits.

In September 2014, the Coast Guard issued a Safety Alert on the problem of overhead clearance and air draft. Over an 11-year period, the Coast Guard counted 205 air-draft-related incidents in which a vessel or cargo struck a bridge span. Additional incidents occurred at overhead power cables. 

Most of those casualties involved the towing industry, and soon the Towing Safety Advisory Committee (TSAC) will issue recommendations in an effort to address the risk.

“Statistically, towing vessels and barges are the most likely to be involved in bridge strikes where air draft is a factor,” the Coast Guard said in the Safety Alert. 

“Barges equipped with or that carry land-based cranes not properly stowed and those fitted with mooring spuds not properly adjusted are the most commonly involved components in overhead bridge allisions,” the authors wrote. “These incidents have resulted in loss of millions of dollars in property damage and inconvenience to entire communities who rely on the bridges and power cables.”

Two areas where complacency has led to serious accidents are a lack of awareness of the height of cargoes, particularly cranes, and the failure of bridge tenders to open drawbridges fully.

The Coast Guard’s Towing Vessel National Center of Expertise (TVNCE) developed last year’s Safety Alert in conjunction with the Office of Investigations and Casualty Analysis. Roy Murphy, the TVNCE’s senior marine inspector, said an impetus for the alert was a fatal accident a month earlier in New Orleans. Capt. Michael Collins, 46, was killed when a barge-mounted crane struck the underside of the Florida Avenue Bridge and fell onto the wheelhouse of his tugboat, Cory Michael.

In October 2013, the top of a crane on a barge struck the nearby Lapalco Bridge and resulted in an allegation that no licensed captain was aboard and a deck hand was at the helm. Authorities in Jefferson County said barge cargoes have struck that bridge three other times in recent years. In those other cases, the captain inaccurately assumed that the overhead clearance was sufficient.

In 2008, a towboat captain and navigation officer were charged with negligence and misconduct after a crane they were towing struck the McTeer Bridge over the Intracoastal Waterway in South Carolina. That bridge was closed for five days after the incident.

Good communication between the towing operator and the customer is a key first step in preventing these accidents, because ultimately the vessel master needs reliable data, said Holly Reister, safety director at the American Waterways Operators (AWO).

“You need to have confidence that the towing operator knows the dimensions of the equipment, so you don’t have an inaccurate measurement,” Reister said.

Reister emphasized that each operator should develop its own procedures, customized for its vessels and waterways visited. The AWO’s Responsible Carrier Program offers sample bridge transit policies — for coastal and inland — that can be used as a format guide. The samples say all personnel should be aware of the procedures and it is the job of the watch officer to follow the practices, brief the crew on the transit and determine a safe speed.

Before approaching a bridge, the watch officer should confirm the air draft of the boat and tow, state of the tide or river stage, vertical clearance of the bridge, direction and strength of the current and whether the beam of the combined vessels will safely transit the bridge. 

The Florida Avenue Bridge in New Orleans was the site of a fatal air-draft-related accident last year.

Brian Gauvin

“If there is a question regarding the safe transit of the bridge, the officer responsible for the transit is to abort the approach and stop or turn the vessel around while it is still safe to do so,” the AWO’s sample coastal policy says. 

TSAC has formed an air-draft subcommittee to make recommendations to the Coast Guard. The resulting report may be issued before summer, said Mike Caliendo, who headed the subcommittee.
Caliendo, vice president of the transportation group at Andrie Inc. in Muskegon, Mich., said the TSAC report will suggest a set of best practices. Examples include: Air draft of vessels should be posted at all control stations; the towing safety management system should include a written description of the master’s responsibilities with regard to air-draft safety; and the safety management system should describe additional procedures for “close tolerance” transit, i.e., instances when there is enough clearance but just barely. 

If the height of a tall cargo is static, the TSAC panel wants the height to be posted and readily available to the towing master. If the height is not static, as for crane stowage or spuds, the circumstances should be provided by the cargo owner in writing.

“In lieu of regulatory change … we are going to recommend that those best practices be in the towing safety management systems,” Caliendo said. “We’re going to recommend that the third parties be held accountable for providing inaccurate air-draft information to the towing vessel masters.”

In a letter to the Coast Guard last year, the AWO said it was aware of a casualty case in which a state department of transportation had posted incorrect vertical clearance information for the bridge that was struck.

Caliendo said the TSAC panel wants bridge tenders to be instructed to “open fully for any passage.”

In the case of the Cory Michael fatality, Murphy said the Coast Guard is investigating whether the captain knew the true height of his cargo and whether the bridge tender opened the bridge only partially. 

“The bridges should be opened promptly and fully,” Murphy said. “There should not be a partial opening of a drawbridge.”

The Safety Alert strongly recommends that operators ensure that every officer of the watch knows the air draft of the vessel and tow and is aware of the available clearance at bridges, power cables and other overhead obstructions — and not use lazy guesswork. They should ensure that “assumptions are not made regarding a vessel or its cargo’s air draft or of bridge heights. Specific data must be known when planning transits,” the alert said.

Ultimately, the Coast Guard would like towing crews to develop a culture in which they are as cognizant of overhead clearance as they are of water draft, and to make attentiveness to air draft a natural part of their routine.  

“They are very good at under-keel clearances, and they know that, and they think in terms of that all the time,” Murphy said. “They may not think of air clearance. Remember that this is a critical element in the safety of navigation.”

By Professional Mariner Staff