Office of Naval Research - National Transportation Library

3-2 Requirements for Viable SSS ServiceShippers and carriers have different requirements for a viable freight service. Researchfindings suggest that for a carrier, the primary requirement for a sustainable service is aminimum volume commitment; for a shipper, the primary requirement for using a service isreliability. A feedback loop or vicious cycle might be at the heart of much of the performancegap today: lack of service reliability for a SSS carrier may often be tied to the lack of volumecommitment. 34Shipper Service RequirementsFor the shipper, the critical service requirement for committing any level of cargo to SSScarriers is service reliability, followed by cost and transit time. A study on the feasibility of acontainer-on-barge (COB) movement of cargo within the freight corridor served by the Portof Mobile and the inland waterway system for the Alabama Freight Mobility programindicated that shippers give the reliability of the shipment arrival the highest priority (with 48percent considering it the highest priority), followed by cost (a high priority for 37 percent ofthe survey respondents) and transit times (high priority for 15 percent of respondents.) Thestudy found that longer transit times are not necessarily detrimental to SSS markets andconcluded with the following statement:“Alternative modes need not be faster or cheaper; they can be competitive if they arereliable.” 35Service unreliability has traditionally been caused by a combination of three factorsprevailing in tug-barge service: unpredictable service hours arising from weather-relatedvulnerabilities and seasonality of service, lack of scheduled services because of lack ofvolume commitment, and inherent delays caused by the difficulty of controlling the tugbargecombination coupled with the need to switch gears when entering the harbor. TheAlabama Freight Mobility Study described some of these root causes of service unreliabilityin tug-barge operations: 36a) Weather delays are often caused by uncertainties of towing a barge in a heavy storm;towed barges must often wait for seas to subside before crossing, particularly whenhazardous materials and petroleum products are carried.b) Difficulty of controlling towed barges in congested waterways and the frequent needfor helper tugs in port add to service unreliability; tug-barge tows face delays becausethey have to wait to cross the harbor entrance; once in the harbor they face furtherdelays because they must switch from towing gear to pushing gear;34 “Alabama Freight Mobility Study, Phase I: Business Perspectives on the Feasibility of Container-on-BargeService,” April 9, 2007.35 “Alabama Freight Mobility Study, Phase I: Business Perspectives on the Feasibility of Container-on-BargeService,” Prepared for the Coalition of Alabama Waterway Association, prepared by Hanson ProfessionalServices, Inc., Nashville, Tennessee, April 9, 2007.36 “The Articulated Tug/Barge – AT/B: The History and State of the Art,” Robert P. Hill, President, Ocean gtug& Barge Engineering Corp. Undated.ONR SSS Final Report 33