4
The Ballast Water Vector

As discussed in the preceding chapter, ships’ ballast water has been identified as the leading vector for recorded introductions of aquatic invasive species (AIS) into the Great Lakes since the opening of the St. Lawrence Seaway in 1959. Thus, the characteristics of the ballast water vector, including the amount of ballast water carried by a vessel, the provenance of that ballast water, and details of the vessel’s ballasting operations, are important items to be considered in seeking to eliminate further AIS introductions.

This chapter describes the three categories used by the committee to group the vessels transiting the seaway: transoceanic, coastal, and inland. The characteristics of these three vessel fleets and of typical vessels in each are then described briefly. The section on vessel operations explains the terminology used to describe a vessel’s ballast condition and then discusses typical ballasting patterns for each of the vessel categories and current understanding of the associated risks of AIS introduction. The chapter concludes with a description of current measures aimed at preventing further introductions of AIS into the Great Lakes by vessels transiting the seaway.

VESSELS TRANSITING THE SEAWAY

Vessels transiting the St. Lawrence Seaway are frequently assigned to one of two categories: ocean vessels, sometimes referred to as “salties,” which are involved in international trade with countries outside of North America; and “lakers,” all of which operate within the Great Lakes St. Lawrence Seaway (GLSLS) system (see Figure 2-1)



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4 The Ballast Water Vector As discussed in the preceding chapter, ships’ ballast water has been identified as the leading vector for recorded introductions of aquatic invasive species (AIS) into the Great Lakes since the open- ing of the St. Lawrence Seaway in 1959. Thus, the characteristics of the ballast water vector, including the amount of ballast water car- ried by a vessel, the provenance of that ballast water, and details of the vessel’s ballasting operations, are important items to be con- sidered in seeking to eliminate further AIS introductions. This chapter describes the three categories used by the commit- tee to group the vessels transiting the seaway: transoceanic, coastal, and inland. The characteristics of these three vessel fleets and of typ- ical vessels in each are then described briefly. The section on vessel operations explains the terminology used to describe a vessel’s bal- last condition and then discusses typical ballasting patterns for each of the vessel categories and current understanding of the associated risks of AIS introduction. The chapter concludes with a description of current measures aimed at preventing further introductions of AIS into the Great Lakes by vessels transiting the seaway. VESSELS TRANSITING THE SEAWAY Vessels transiting the St. Lawrence Seaway are frequently assigned to one of two categories: ocean vessels, sometimes referred to as “salties,” which are involved in international trade with countries out- side of North America; and “lakers,” all of which operate within the Great Lakes St. Lawrence Seaway (GLSLS) system (see Figure 2-1) 63

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64 Great Lakes Shipping, Trade, and Aquatic Invasive Species and some of which also operate within Canadian and U.S. coastal waters.1 For the purposes of this report, however, the committee deemed it more appropriate to group vessels transiting the seaway ac- cording to their voyage patterns and associated risk of introducing AIS into the Great Lakes through their ballasting operations. Conse- quently, it considered three categories of vessel transiting the seaway: • Transoceanic vessels enter the GLSLS system after operating out- side of the Canadian and U.S. exclusive economic zones (EEZs). Transoceanic vessels currently operating into the Great Lakes are all foreign-flagged. • Coastal vessels operate within the continental EEZ (i.e., not more than 200 nautical miles from shore) before entering the GLSLS system. Vessels currently operating in coastal trade are predomi- nantly Canadian-flagged and capable of performing transoceanic voyages but restrict their trade to coastal areas for commercial reasons. Foreign-flagged vessels also participate in this coastal trade on an occasional basis. • Inland vessels are Canadian- or U.S.-flagged vessels certified to operate solely within the inland waters of the GLSLS system, which extend as far eastward as Anticosti Island in the Gulf of St. Lawrence.2 Thus, transoceanic vessels, as defined here, correspond to the ocean vessel category used in the seaway traffic reports3 (and else- where), while the coastal and inland vessels correspond to the laker category used in the traffic reports. Subdividing the laker category into two groups is important both in examining the risks of AIS introduction posed by different vessels and in considering oppor- 1 The U.S.-flagged domestic lakes fleet comprises approximately 60 vessels, mostly bulk freighters, the majority of which are too large to transit the Welland Canal. Hence, these vessels trade exclu- sively on Lakes Erie, Huron, Michigan, and Superior, carrying iron ore and coal for domestic steel production, coal for electric power generation, and limestone for cement manufacturers. The smaller units of this fleet may transit the seaway on an occasional basis. 2 A few of these vessels are permitted to make occasional summer voyages further into the Gulf of St. Lawrence (i.e., into coastal waters) under strict limitations imposed by the flag administration. 3 The seaway traffic reports are available on the GLSLS system’s website (www.greatlakes-seaway.com).

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The Ballast Water Vector 65 tunities for and constraints on ballast water management to reduce these risks. However, the coastal and inland components cannot be readily extracted from the reported laker traffic. The definition of coastal vessels used in this report is a catchall covering all vessels that (a) enter the GLSLS system after trading within the continental EEZ and (b) do not fall under the defini- tions of either transoceanic or inland vessels. Hence, this defini- tion may not be related to the definitions used in either Canadian or U.S. regulations. FLEET AND VESSEL CHARACTERISTICS Transoceanic Vessels The fleet of transoceanic vessels currently using the seaway is flagged in more than 30 foreign countries (i.e., excluding Canada and the United States). The majority of these vessels belong to a stable, core group of vessels purpose-built for the trade and operating on reg- ular runs into the Great Lakes every navigation season (liner trades). If cargo demand dictates, these vessels make multiple en- tries into the Great Lakes through the seaway during a single nav- igation season. The balance of the transoceanic fleet is made up of tramp vessels, either on single voyages into the Great Lakes or chartered in periodically by the liner operators to satisfy demand. The size of the transoceanic fleet, and particularly the tramp component, can fluctuate considerably from year to year. The fluc- tuations reflect not only variations in Great Lakes trade, notably grain exports and steel imports, but also changes in trading op- portunities elsewhere in the world and variations in charter rates for ocean vessels. Since the introduction of Lakes-max oceangoing bulk carriers4 in the early 1980s, the typical fleet size has ranged 4 The term “Lakes-max” describes a subset of handy-size bulk carriers that have been designed to optimize cargo carriage within the constraints of the seaway’s lock dimensions and draft restric- tions. Initially designed on a 10:1 length-to-breadth ratio similar to maximum-size inland vessels, the latest vessels are built to a lesser ratio that is more compatible with the stresses imposed on a ship’s hull in ocean trade.

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66 Great Lakes Shipping, Trade, and Aquatic Invasive Species from 200 to 300 vessels annually (Colautti et al. 2003). Over the past 5 years (2003–2007), the number of inbound transoceanic vessels entering the seaway each navigation season has averaged 233, with a low of 214 and a high of 260.5, 6 The transoceanic fleet using the seaway comprises three distinct groups of vessels. Large dry bulk carriers carrying imports of steel and raw materials and grain exports predominate. Smaller dry bulk and project cargo carriers carry imports of manufactured goods un- suitable for container shipment, such as turbines and ancillary equipment for wind energy farms being developed in New York, Wisconsin, and Ontario, as well as other processed steel products, and exports ranging from fabricated assemblies to bulk grain. Finally, chemical tankers carry imports and exports of bulk liquid chemicals in parcels, rum, liquid fertilizers, animal fats, and vegetable oils. The cargo-carrying capacities of these ships range from as little as 2,500 deadweight tonnes (DWT) up to 38,300 DWT, with the majority of vessels being bulk carriers in the range of 20,000 to 38,000 DWT. Within the restricted depths of the seaway, the larger ships are limited to less than 30,000 DWT. Their water ballast– carrying capacities range from 1,200 to 24,500 cubic meters. The transoceanic fleet servicing the Great Lakes is constantly evolving technically to maximize performance given the vagaries of the system. Included in this technical evolution have been changes in design and outfitting of ballast systems to enable more thorough evacuation of ballast tanks. While the oldest vessels, built in the early 1980s, are nearing the end of their useful service life, more than 50 modern ships built specifically for the Great Lakes trade have 5 Personal communication to Phil Jenkins, committee member, from the St. Lawrence Seaway Management Corporation, January 2008. 6 It is important to distinguish between the numbers of transoceanic vessels entering the Great Lakes through the seaway each navigation season and the numbers of inbound vessel transits recorded in the seaway traffic reports. Because some vessels make multiple entries during any given navigation season, the number of vessels is less than the number of inbound vessel transits. A transoceanic ves- sel carries a risk of introducing new invaders each time it enters the Great Lakes, so the number of in- bound vessel transits is often used in discussing AIS introductions. However, when the installation of shipboard equipment aimed at preventing such introductions (ballast water treatment or monitor- ing systems, for example) is considered, the number of vessels is clearly the more relevant figure.

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The Ballast Water Vector 67 been introduced into service since 2000. Companies dedicated to serving the Great Lakes operate these ships on both owned and char- tered bases and enter them into the trade as cargo demands dictate. Coastal Vessels The Canadian domestic fleet using the GLSLS system comprises al- most 70 vessels. While all these vessels are recorded as lakers in the seaway traffic data, there is a subset of more than 20 vessels that trade beyond the inland waters of the GLSLS system and are more properly described as coastal. These vessels can service the eastern seaboard of the North American continent, from Nunavut in the north to Florida in the south, and in many respects are a micro- cosm of the entire trade through the seaway. The dry cargo vessels range from Lakes-max self-unloading bulk carriers and gearless bulk carriers to smaller geared bulk carriers and project cargo ves- sels, with cargo-carrying capacities from 3,000 to 39,000 DWT and ballast capacities from 2,000 to 25,000 cubic meters. Ten oil tankers ranging from 9,500 to 21,000 DWT also operate regularly in coastal trade, and another four or five similar-sized foreign-flagged tankers are chartered into the trade under a flag waiver by the major oil com- panies during periods of peak demand for fuel and heating oils. In addition, while a number of the Canadian tankers are classed to carry both oil and chemicals, Canada lacks the capacity to train of- ficers for specialized cargo trades and thus to man these ships for chemical carriage. Consequently, domestic movements of bulk liquid chemicals are made through the seaway by foreign-flagged chemical tankers chartered in under the same flag waiver conditions. The committee’s charge addresses specifically AIS introductions by “vessels transiting the St. Lawrence Seaway.” However, Cana- dian dry cargo vessels operating between Montreal (a freshwater port) and Newfoundland and tankers operating between Saint John, New Brunswick, and Montreal could transfer AIS between coastal waters and the freshwater Great Lakes ecosystem, even though they do not enter the Montreal–Lake Ontario (MLO) sec- tion of the seaway.

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68 Great Lakes Shipping, Trade, and Aquatic Invasive Species Inland Vessels The remaining domestic GLSLS fleet, excluding the coastal vessels described above, comprises 43 vessels or tug–barge units that are ca- pable of transiting the seaway locks but are restricted by their design scantling7 from proceeding beyond the limits of Canadian inland waters (east of Anticosti Island). These vessels are primarily dry bulk carriers, the majority of which are self-unloaders ranging in capac- ity from 16,000 to 36,000 DWT with ballast capacities of 10,000 to 20,000 cubic meters. The self-unloading vessels, 30 in number, are both operationally and environmentally efficient carriers capable of delivering cargoes to locations with little port infrastructure as noted in Chapter 2, yet having sufficient flexibility to be used in the coal, iron ore, potash, aggregates, salt, and grain trades. Two of the barge units and a further small bulk carrier are specialized carriers of bulk cement with the capability to both load and self-unload the material without any dust release into the local environment. In addition, 16 gearless bulk carriers are used primarily in the export grain transshipment trade. These vessels backhaul iron ore for part of their return passage from the grain transfer elevators on the lower St. Lawrence River to those on the upper lakes. By ocean-shipping standards, the inland fleet is elderly, with the older vessels built in the 1960s and the last completely new vessel delivered in 1985. It is, however, a fleet best described as a work in progress, since life extension is a specialty of the Great Lakes ship- ping industry. Such life extension is possible because the vessels operate for the most part in a relatively benign freshwater envi- ronment, as opposed to a saltwater ocean environment, and the winter layup of almost 3 months provides an opportunity for ex- tensive steel replacements and major machinery replacements with- out a forced withdrawal from commercial service. Replacement of the complete forebody (the cargo-carrying section) is not unusual, and at the same time the vessel dimensions can be changed to ben- efit from draft and beam tolerance changes implemented by the seaway corporations. In the case of self-unloaders, cargo systems 7 “Scantling” refers to the dimensions of the structural parts of a vessel.

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The Ballast Water Vector 69 can also be upgraded with the latest technology. Many older vessels in the inland fleet now include only a part of the original vessel. VESSEL OPERATIONS Ballast Condition Vessels carrying little or no cargo carry ballast water to compen- sate for shear forces on their hulls and to achieve the longitudinal, transverse, and directional stability necessary for safe operation. Whether navigating in confined waters where precise steering is needed or in the open ocean where maintaining steerage in all sea and swell conditions is imperative, adequate submergence of the hull, and particularly the propeller(s) and rudder(s), is of para- mount importance. Traditionally, a vessel may be identified as being in one of three ballast conditions.8 A vessel that is not carry- ing any cargo and that has water in its ballast tanks is described as being in ballast. A vessel operating with some cargo and some bal- last is described as being with ballast. And a vessel fully laden with cargo and with only unpumpable residual water and sediment in its ballast tanks may be described as having no ballast on board and is frequently referred to as a NOBOB. In the context of efforts to prevent further AIS introductions into the Great Lakes, a distinction has historically been made be- tween vessels in ballast or with ballast that are able, in principle, to exchange the water in their ballast tanks with ocean water during the course of a voyage and NOBOBs that are unable to conduct such ballast water exchange (BWE, see Box 4-1 on pages 78–79) because their ballast tanks contain only unpumpable residual water and sediment (see later).9 Thus, the term BOB (“ballast on 8 A more detailed description of ballast water and ships is provided elsewhere (NRC 1996, Chapter 2). 9 Few ships, particularly in the dry bulk cargo trade that predominates on the Great Lakes, are capa- ble of evacuating their ballast tanks completely during the course of a deballasting/cargo loading cycle (Jenkins 2007). A survey of NOBOB vessels on the Great Lakes indicated that the volume of unpumpable residual water and sediment in their ballast tanks averaged 60 cubic meters per vessel (Bailey et al. 2003).

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70 Great Lakes Shipping, Trade, and Aquatic Invasive Species board”) is often used to distinguish vessels in ballast or with ballast from those in NOBOB condition. As discussed later in this chapter, both ballasted vessels and NOBOBs can introduce AIS into the Great Lakes through their ballasting operations. Whereas AIS introductions by ballasted ves- sels have been reported in many countries, AIS introductions by NOBOBs are largely confined to the Great Lakes (Jenkins 2007). Thus, some brief comments about the term NOBOB are appro- priate in the present context. Many ships entering the seaway laden with cargo carry small amounts of ballast to attain the necessary trim10 and to meet the air draft limitations posed by bridges and power lines in various loca- tions throughout the GLSLS system. In addition, a number of project cargo vessels have entered the Great Lakes in recent years carrying large windmill components manufactured in Europe and destined for wind farms in the Great Lakes region and beyond. Carriage of these large and sometimes unwieldy components often requires a vessel to carry a limited amount of ballast water to counter- balance irregular cargo stowage and to achieve the necessary sta- bility. These groups of vessels are not strictly NOBOBs because they carry some ballast, albeit a limited amount. From an AIS per- spective, however, they are essentially NOBOB vessels that cannot conduct BWE and have to be treated accordingly for the purposes of ballast water management and inspection (see later). In seeking to prevent AIS introductions into the Great Lakes, an incoming vessel’s NOBOB status needs to be determined at Quebec City, where fresh and tidal waters merge, as opposed to where the vessel enters the MLO section of the seaway. Inbound vessels en- tering the St. Lambert Lock above Montreal may already have called at one of the freshwater ports on the Saguenay River or on the St. Lawrence River between Quebec City and Montreal to dis- charge some or all of their cargo. Of particular concern are vessels that enter the GLSLS system fully laden with cargo and discharge all this cargo at one of the freshwater ports, where they take on 10 A vessel’s trim is defined as the difference between its after and forward drafts.

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The Ballast Water Vector 71 freshwater ballast before transiting the seaway and entering the Great Lakes. Although such vessels are BOBs when they transit the seaway, they have to be inspected and treated as NOBOBs because they entered the freshwater part of the GLSLS system with no ballast on board. As the above discussion indicates, a simple “BOB” or “NOBOB” designation may be convenient in some cases. However, for the pur- poses of preventing further AIS introductions into the Great Lakes, it is important to have more detailed information about a vessel’s ballast condition and to understand practical constraints on its bal- lasting capabilities and the associated implications for managing its ballast water. Inspection protocols for vessels entering the GLSLS system take account of these complexities (see later). Typical Ballasting Patterns and Associated Risks of AIS Introduction Transoceanic Vessels Efforts to prevent further ballast-mediated AIS introductions into the Great Lakes focused initially on transoceanic vessels carrying ballast. Ballast water loaded by these vessels in regions outside of the Great Lakes entrains viable freshwater species that are often discharged during cargo loading in Great Lakes ports and may re- sult in AIS introductions. Before the introduction of Canada’s Vol- untary Ballast Water Exchange Program for ships entering the Great Lakes in 1989 and the subsequent implementation of ballast water management regulations by the U.S. Coast Guard in 1993, transoceanic vessels entered the GLSLS system loaded with fresh, brackish, or marine ballast water probably taken on board at one or more overseas ports of departure. These vessels entered the Great Lakes primarily to collect grain from the export terminals in Toledo, Chicago, Milwaukee, Duluth, or Thunder Bay, where they would discharge their ballast water—and AIS contained therein. It is almost certain that such notorious invaders as zebra mussels (Dreissena polymorpha), quagga mussels (D. rostriformis bugensis), and round gobies (Neogobius melanostomus) were introduced in

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72 Great Lakes Shipping, Trade, and Aquatic Invasive Species freshwater ballast of a BOB vessel, since these species are not tol- erant of saline water and do not produce viable resting stages, such as cysts, that could tolerate saline conditions. Because the ballast tanks of NOBOBs contain only unpumpable residual water and sediment, these vessels were not initially identified as a possible vector for AIS introductions. However, the ongoing discovery of new AIS in the Great Lakes after the implementation of the ballast exchange regime (see later) drew attention to the role of NOBOBs in introducing AIS (Aquatic Sciences, Inc., et al. 1996). Since the early 1980s, the numbers of NOBOB vessels entering the GLSLS system have been increasing steadily. Such vessels cur- rently make up the vast majority of transoceanic vessels entering the system, with only a small percentage of vessels entering in bal- last. Colautti et al. (2003) estimated that the number of vessel en- tries in ballast made up approximately 10 percent of inbound traffic to the Great Lakes during the 1990s. The trend for relatively few transoceanic vessels entering in ballast appears to be continu- ing, with 54 (10.3 percent) of the 523 inbound vessel transits through the MLO section of the seaway during the 2005 navigation season being in full ballast condition and 64 (9.5 percent) out of 676 inbound transits in ballast in 2006.11 Today, most transoceanic vessels enter the GLSLS system fully laden with import cargoes and report NOBOB status. A majority of the NOBOB vessels visit multiple ports while trav- eling upstream, discharging cargo and loading Great Lakes ballast water to maintain safe operating parameters (see Figure 4-1).12 This water mixes with the residual water in the ballast tanks, and at a final destination port in the Great Lakes—typically Thunder Bay or Duluth–Superior—the combined solution is discharged when outbound cargo (grain) is loaded. Unless preventive measures 11 Data from Great Lakes St. Lawrence Seaway Traffic Reports at www.greatlakes-seaway.com. 12 Figure 4-1 shows a typical transit of a transoceanic NOBOB vessel on the Great Lakes, as reported by Colautti et al. (2003). The vessel illustrated made three stops inbound to off-load cargo before heading to Duluth–Superior to load grain; other vessels may stop only once or twice before head- ing to Duluth–Superior or Thunder Bay.

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FIGURE 4-1 Typical transit of a transoceanic NOBOB vessel on the Great Lakes. The inbound leg includes stops in Hamilton, Cleveland, and Burns Harbor, where cargo is discharged and Great Lakes ballast water loaded. This water mixes with residual water of fresh, brackish, or saline origin in the vessel’s ballast tanks. The vessel terminates the inbound leg of its voyage with a trip to Lake Superior, where the mixed ballast water is discharged (together with surviving species from the residual ballast) when outbound cargo is loaded in Duluth–Superior.

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76 Great Lakes Shipping, Trade, and Aquatic Invasive Species throughout the GLSLS system, to explore and elucidate possible mechanisms by which AIS may be distributed by inland vessels. CURRENT MEASURES TO PREVENT AIS INTRODUCTIONS INTO THE GREAT LAKES Current measures aimed at preventing further introductions of AIS into the Great Lakes by vessels transiting the seaway focus on ships’ ballast water as the leading invasion vector. The following discussion summarizes these measures and identifies the ballast water management requirements for the three categories of vessel transiting the seaway (transoceanic, coastal, and inland). Inspec- tion and enforcement measures to ensure compliance with the var- ious rules and regulations are then outlined. Bodies Issuing Rules and Regulations Rules and regulations specifying ballast water management re- quirements for vessels entering the GLSLS system are issued by the Canadian and U.S. federal governments and by the joint Seaway Authorities comprising the Canadian St. Lawrence Seaway Man- agement Corporation (SLSMC) and the U.S. St. Lawrence Seaway Development Corporation (SLSDC). In Canada, the Ballast Water Control and Management Regula- tions issued pursuant to the Canada Shipping Act of 2006 aim to protect waters under Canadian jurisdiction from nonindigenous aquatic organisms and pathogens that can be harmful to ecosys- tems.13 In the United States, the Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 directed the U.S. Coast Guard to issue regulations to prevent the introduction and spread of aquatic nuisance species into the Great Lakes through the ballast water of vessels and establish civil and criminal penalties for vio- lating these regulations. Mandatory requirements for ballast water 13 TP 13617 E, A Guide to Canada’s Ballast Water Control and Management Regulations, is avail- able on the Transport Canada website (www.tc.gc.ca).

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The Ballast Water Vector 77 management for the Great Lakes went into effect in 1993 (33 CFR 151). In addition, Section 30 (2) of the Seaway Practices and Pro- cedures issued jointly by the Seaway Authorities specifies ballast water management practices with which vessels must comply be- fore being granted clearance to transit the seaway.14 In contrast to the situation in Canada, where the federal govern- ment has sole jurisdiction over all matters dealing with shipping, in- dividual U.S. states may choose to establish their own ballast water legislation to supplement federal regulations. Michigan is currently the only Great Lakes state to have taken such action, although oth- ers are considering following suit. Following the passage of state leg- islation in 2005, vessels coming from outside the GLSLS system and engaging in port operations in Michigan are now required to com- ply with the state’s ballast water control requirements.15 Current Ballast Water Management Requirements The ballast water management techniques (BWE, saltwater flush- ing, shipboard treatment, and shore-based treatment) specified in the various rules and regulations discussed below are described briefly in Box 4-1. Canadian regulations require vessels coming from outside the Canadian EEZ (i.e., transoceanic vessels and coastal vessels com- ing from the U.S. EEZ) to use, either separately or in combination, the following ballast water management measures: 1. Exchange of ballast water or saltwater flushing of ballast tank residuals, 2. Shipboard treatment of ballast water using an accepted tech- nology option, 3. Discharge of ballast water to a shore-based reception facility, or 4. Retention of ballast water on board the ship.16 14 The Seaway Practices and Procedures are available on the GLSLS system website (www. greatlakes-seaway.com). 15 Further information is available on the Michigan Department of Environmental Quality website (www.michigan.gov/deq). 16 These ballast water management requirements apply to all vessels entering waters under Canadian jurisdiction, with a few exceptions. They are not limited to vessels entering the GLSLS system.

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78 Great Lakes Shipping, Trade, and Aquatic Invasive Species BOX 4-1 Ballast Water Management Techniques Ballast Water Exchange BWE involves replacing (exchanging) a vessel’s ballast water with ocean water. There are two principal methods of exchange: rebal- lasting and dilution. The reballasting or empty-refill method in- volves emptying and then refilling a ballast tank, whereas the dilution or flow-through method admits water to the tank at the same time as water is discharged. In either case, BWE has two major effects on biota in ballast tanks. First, because BWE involves replacing 95 to 99 percent of water in the tanks, an equal percent- age of organisms is removed by the dilution effect, assuming a homogeneous distribution of flora and fauna. In some cases, popu- lations of some species may be completely purged or rendered low enough that recovery and establishment are not likely once any remaining organisms are released. Second, BWE may involve replacing freshwater ballast with open ocean water (saltwater), resulting in osmotic stress for most freshwater organisms resident in the tank. Consequently, BWE conducted by vessels moving between European freshwater ports and the Great Lakes is ex- pected to reduce both the abundance and diversity of freshwater life dramatically. In situ studies of invertebrates in ships traveling between the Great Lakes and Europe illustrated that BWE sharply reduced both diversity and abundance of freshwater invertebrates in ballast tanks (Gray et al. 2007). Saltwater Flushing NOBOB vessels are unable to conduct BWE because their ballast tanks contain only unpumpable residual water and sediments. The alternative to BWE for NOBOBs is saltwater flushing, which is accom- plished by allowing a limited amount of saltwater to slosh around in an individual ballast tank as a result of the ship’s rolling and pitching motion during passage (Reid et al. 2007). This agitation resuspends trapped sediments and provides a salinity shock to biota, which are then discharged into the open ocean. Thus, saltwater flushing pro- (continued)

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The Ballast Water Vector 79 vides the dual effects of dilution and salinity shock that are achieved with BWE, but it applies them to empty (NOBOB) tanks. Both BWE and saltwater flushing techniques are currently used by vessels operating into the Great Lakes. Shipboard Ballast Water Treatment The use of shipboard systems to kill AIS in ballast water is widely viewed as offering greater operational flexibility than either BWE or saltwater flushing, as well as the potential for greater effectiveness. A variety of proven water treatment technologies are available, but adapting them for shipboard application presents major technical challenges (see, for example, NRC 1996). However, important progress has been made in recent years, largely in response to the International Maritime Organization’s proposed ballast water management requirements (IMO 2004), and shipboard ballast water treatment systems are expected to become commercially available by 2009 (Lloyd’s Register 2007). Some prototype systems have been installed on operational vessels, at least three of which are trading into the GLSLS system, but shipboard ballast water treatment is not currently a proven method of ballast water management in an operational environment. Shore-Based Ballast Water Treatment Shore-based ballast water treatment avoids some of the chal- lenges associated with shipboard application of water treatment methods. However, bulk handling of ballast water from a ship to a shore-based facility is complex. In addition, the economics of shore-based ballast water treatment facilities have been identified as problematic by a number of authors (see, for example, NRC 1996). There are currently no shore-based ballast water treatment facilities available to vessels operating on the GLSLS system, although Wisconsin recently announced that the state will spend US$6 million to invest in experimental shore-based ballast water treatment systems for its Great Lakes ports (Egan 2008).

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80 Great Lakes Shipping, Trade, and Aquatic Invasive Species For Option 1, transoceanic vessels are required to conduct mid- ocean BWE during ballast-laden voyages in an area 200 nautical miles from any shore and in water 2,000 meters deep whenever possible, before entering waters under Canadian jurisdiction. Transoceanic NOBOB vessels are required to conduct saltwater flushing in similar areas on their passage to the Great Lakes to elim- inate fresh or brackish water residuals in their ballast tanks. Coastal vessels must comply with similar requirements, except that BWE or saltwater flushing is to be conducted in an area at least 50 nautical miles from shore where the water depth is at least 500 meters.17 U.S. regulations require that all vessels entering U.S. waters in ballast after operating outside the U.S. EEZ manage their ballast water by undertaking mid-ocean BWE, retaining their ballast water on board, or using an alternative environmentally sound method of ballast water management preapproved by the U.S. Coast Guard. In the case of coastal vessels coming from the Canadian EEZ that elect to manage their ballast water by BWE, this process is to be conducted within designated exchange areas. Since August 2005, NOBOBs entering U.S. waters have been strongly encouraged, but not required, to conduct saltwater flushing before entering the Great Lakes. From the beginning of the 2008 navigation season, however, the seaway regulations require all transoceanic NOBOB vessels to conduct saltwater flushing before entering the Great Lakes, regardless of whether their destination is a U.S. or Canadian port.18 U.S. regulations also require that every vessel equipped with ballast tanks that operates in U.S. waters and is bound for ports or places in the United States comply with a suite of management practices designed to minimize the quantity of aquatic organisms it may be carrying (33 CFR 151.2035, Subpart D). 17 Under certain circumstances, vessels may also conduct BWE or saltwater flushing in designated exchange zones within the Canadian EEZ. 18 A notice of proposed rulemaking issued by the SLSDC (2007) aimed to harmonize U.S. and Canadian requirements for saltwater flushing by transoceanic vessels operating in the binational waters of the GLSLS system. In February 2008, the Seaway Practices and Procedures were updated to include the saltwater flushing requirement for transoceanic NOBOB vessels.

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The Ballast Water Vector 81 The carriage of vessel-specific ballast water management plans and compliance with mandatory record-keeping and reporting regimes are also required by both Canada and the United States. In addition, the Seaway Practices and Procedures mandate that every vessel entering the seaway after operating beyond the EEZ (i.e., all transoceanic vessels) must agree to respect the Shipping Federation of Canada’s Code of Best Practices for Ballast Water Management (2000) while operating anywhere within the Great Lakes and the seaway. Every other vessel entering the seaway (i.e., coastal and inland vessels) must agree to comply with the Voluntary Management Practices to Reduce the Transfer of Aquatic Nuisance Species Within the Great Lakes by U.S. and Canadian Domestic Ship- ping (Lake Carriers’ Association and Canadian Shipowners Associ- ation 2001) while operating anywhere within the Great Lakes and the seaway. Table 4-1 summarizes current ballast water management re- quirements for the three categories of vessel transiting the seaway (transoceanic, coastal, and inland). In addition to these require- ments, vessels engaging in port operations in Michigan that have operated beyond the mouth of the St. Lawrence River are required to purchase a permit from the Michigan Department of Environ- mental Quality (MDEQ). This permit applies to vessels that either engage in port operations and do not discharge ballast water or dis- charge ballast water treated by a method approved by MDEQ.19 Inspection and Enforcement Procedures In January 2006, the agencies that inspect, test, and monitor the ballast water of vessels entering the GLSLS system—Transport 19 There is a $75 application fee for the certificate of coverage under the general permit and a $150 annual renewal fee. The certificate of coverage under the general permit is effective for 5 years. The approved treatment methods are hypochlorite treatment, chlorine dioxide treatment, ultra- violet radiation treatment preceded by suspended solids removal, and deoxygenation treatment. Vessel owners proposing an alternative treatment method may apply for an individual permit. Penalties for noncompliance with the permit range up to $25,000 per day.

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82 Great Lakes Shipping, Trade, and Aquatic Invasive Species TABLE 4-1 Ballast Water Management Requirements for Vessels Entering the GLSLS System Vessel Ballast Ballast Water Management Vessel Origin Destination Status Requirements Transoceanic Vessels Outside Canadian Canadian Great BOB BWE, treatment, discharge and U.S. EEZ Lakes ports to reception facility, or retention Code of Best Practicesa NOBOB Saltwater flushing, treatment, discharge to reception facility, or retention Code of Best Practicesa U.S. Great BOB BWE, retention, or alternative Lakes ports preapproved environmen- tally sound method Code of Best Practicesa Regulated Management Practicesb NOBOB Saltwater flushing mandatory from beginning of 2008 seaway navigation season Code of Best Practicesa Regulated Management Practicesb Coastal Vessels Within Canadian Canadian Great BOB or Voluntary Management Practicesc EEZ Lakes ports NOBOB U.S. Great BOB BWE, retention, or alternative Lakes ports preapproved environmen- tally sound method Regulatedb and Voluntary Management Practicesc Regulatedb and Voluntary NOBOB Management Practicesc Within U.S. EEZ Canadian Great BOB BWE, treatment, discharge Lakes ports to reception facility, or retention Voluntary Management Practicesc NOBOB Saltwater flushing, treatment, discharge to reception facility, or retention Voluntary Management Practicesc Regulatedb and Voluntary U.S. Great BOB or Management Practicesc Lakes ports NOBOB

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The Ballast Water Vector 83 Vessel Ballast Ballast Water Management Vessel Origin Destination Status Requirements Inland Vessels Inland waters of Canadian ports BOB and Voluntary Management Practicesc GLSLS system NOBOB Regulatedb and Voluntary U.S. ports BOB and Management Practicesc NOBOB a Code of Best Practices for Ballast Water Management, Shipping Federation of Canada, Sept. 28, 2000. b 33 CFR 151.2035, Subpart D. c Voluntary Management Practices to Reduce the Transfer of Aquatic Nuisance Species Within the Great Lakes by U.S. and Canadian Domestic Shipping, Lake Carriers’ Association and Canadian Shipowners Association, Jan. 26, 2001. Canada Marine Safety, the U.S. Coast Guard, the U.S. SLSDC, and the Canadian SLSMC—formed a U.S.–Canadian Ballast Water Working Group (BWWG). This initiative aimed to standardize commonly needed information, such as ballast water inspections, verifications, testing, sampling, reports, and data collection, and to optimize the use of available resources to ensure maximum coverage (inspection of every vessel) with no duplication of effort. BWWG has developed a standardized ballast water reporting form, developed and coordinated a memorandum of understanding signed by Transport Canada and the U.S. Coast Guard setting out proce- dures and parameters to conduct joint vessel exams in Montreal, and developed and implemented a standardized GLSLS System Joint Agency Ballast Water Management Inspection Report that captures each agency’s inspection needs. Every vessel entering the GLSLS system from beyond the Cana- dian EEZ is subject to inspection to ensure that the salinity of the ballast, or ballast residuals, in its tanks is greater than or equal to 30 ppt. Highly trained and experienced inspectors follow a strict inspection protocol, prioritized on the basis of risk, that aims to cover all vessels without causing unnecessary delays to shipping. In the case of such vessels discharging their entire import cargo at a Quebec freshwater port outside the seaway and indicating their in- tention to enter the GLSLS system, every attempt is made to con- duct an inspection before the vessel takes river ballast on board

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84 Great Lakes Shipping, Trade, and Aquatic Invasive Species so that the residual salinity can be determined. (As noted earlier, these latter vessels need to be treated as NOBOBs, even though they are carrying ballast when they transit the seaway.) Ballasted vessels that do not conduct open-ocean BWE before entering the St. Lawrence Seaway may be required either to return to sea to conduct BWE or to retain their ballast water on board for their entire voyage through the Great Lakes. In the latter case, a letter of retention is placed aboard. When the vessel later departs the system, the relevant ballast tank or tanks are inspected to ensure compliance with the retention requirement and the letter of reten- tion is removed. A similar procedure is followed for noncompliant ballast tanks on NOBOBs. In 2006, the U.S. Coast Guard issued seven retention letters for vessels going to U.S. ports, and Trans- port Canada issued 25 retention letters for vessels going to Canadian ports (U.S. Coast Guard 2007). As noted earlier, vessels carrying project cargoes, such as wind turbines, require ballast to balance their cargo load. For these vessels, retention of ballast water on board is a far safer option than attempting to conduct BWE. A number of the letters of retention issued during the 2006 navigation season are understood to have been issued to such project cargo vessels. For minor first-time offenses, such as discrepancies in a vessel’s ballast water management plan, records, or reports, the U.S. Coast Guard issues a letter of warning. In Canada, letters of correction are used to instruct a ship’s operator to correct such discrepancies. Information on letters of warning and correction issued in 2006 has been published by the U.S. Coast Guard (2007). Both Canada and the United States have strict systems of fines as additional penalties for failure to comply with ballast water management regulations. CONCLUDING REMARKS Vessels transiting the seaway may be grouped into three categories (transoceanic, coastal, and inland) on the basis of their voyage pat- terns and associated risks of introducing AIS into the Great Lakes through their ballasting operations. Ballast water has historically

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The Ballast Water Vector 85 been the predominant vector for ship-vectored AIS introductions into the Great Lakes since the opening of the seaway in 1959, and current ballast water management regulations aim to prevent further such introductions. As of the beginning of the 2008 navigation season, all transoceanic vessels transiting the seaway are required to conduct BWE (ballasted vessels) or saltwater flushing (NOBOBs) in an effort to prevent further ballast-mediated AIS introductions into the Great Lakes. These measures, if rigorously applied, are expected to reduce con- siderably further AIS introductions by transoceanic vessels. How- ever, coastal vessels also carry a risk of introducing AIS through their ballasting operations, and not all such vessels are currently required to conduct either BWE or saltwater flushing. Ballasted vessels (BOBs) are required to conduct BWE only if they move from one jurisdiction to another (U.S. to Canadian waters, or vice versa), and NOBOBs are required to conduct saltwater flushing only if their voyage takes them from within the U.S. EEZ to a Canadian Great Lakes port. REFERENCES Abbreviations IMO International Maritime Organization NRC National Research Council SLSDC St. Lawrence Seaway Development Corporation Aquatic Sciences, Inc., Philip T. Jenkins and Associates, Ltd., and RNT Consulting. 1996. Examination of Aquatic Nuisance Species Introductions to the Great Lakes Through Com- mercial Shipping Ballast Water and Assessment of Control Options Phase I & Phase II. Canadian Coast Guard. Bailey, S. A., C. D. A. van Overdijk, P. Jenkins, and H. J. MacIsaac. 2003. Viability of In- vertebrate Resting Stages Collected from Residual Ballast Sediment of Transoceanic Vessels. Limnology and Oceanography, Vol. 48, pp. 1701–1710. Bailey, S. A., K. Nandakumar, I. C. Duggan, C. D. A. van Overdijk, T. H. Johengen, D. F. Reid, and H. J. MacIsaac. 2005. In Situ Hatching of Invertebrate Diapausing Eggs from Ships’ Ballast Sediment. Diversity and Distributions, Vol. 11, pp. 453–460.

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86 Great Lakes Shipping, Trade, and Aquatic Invasive Species Colautti, R. I., A. J. Niimi, C. D. A. van Overdijk, E. L. Mills, K. Holeck, and H. J. MacIsaac. 2003. Spatial and Temporal Analysis of Transoceanic Shipping Vectors to the Great Lakes. In Invasive Species: Vectors and Management Strategies (G. M. Ruiz and J. T. Carlton, eds.), Island Press, pp. 227–246. Egan, D. 2008. City’s Port to Clean Ballast. Milwaukee Journal Sentinel, Jan. 17. Gray, D. K., T. H. Johengen, D. F. Reid, and H. J. MacIsaac. 2007. Efficacy of Open-Ocean Ballast Water Exchange as a Means of Preventing Invasions Between Freshwater Ports. Limnology and Oceanography, Vol. 52, No. 6, pp. 2386–2397. IMO. 2004. International Convention for the Control and Management of Ships’ Ballast Water and Sediments. London, United Kingdom. Jenkins, P. T. 2007. Brine as a Treatment Solution for the Control of Aquatic Nuisance Species Introductions into the Great Lakes by NOBOB Vessels. Prepared for Transport Canada Marine Safety by Philip T. Jenkins and Associates, Ltd., Fonthill, Ontario. Kelly, D. W., J. Muirhead, D. D. Heath, and H. J. MacIsaac. 2006. Contrasting Patterns in Genetic Diversity Following Multiple Invasions of Fresh and Brackish Waters. Molecular Ecology, Vol. 15, pp. 3641–3653. Lake Carriers’ Association and Canadian Shipowners Association. 2001. Voluntary Man- agement Practices to Reduce the Transfer of Aquatic Nuisance Species Within the Great Lakes by U.S. and Canadian Domestic Shipping. Jan. 26. Lloyd’s Register. 2007. Ballast Water Treatment Technology: Current Status. June. NRC. 1996. Stemming the Tide: Controlling Introductions of Nonindigenous Species by Ships’ Ballast Water. National Academy Press, Washington, D.C. Reid, D. F., T. H. Joehengen, H. MacIsaac, F. Dobbs, M. Doblin, L. Drake, G. Ruiz, and P. Jenkins. 2007. Identifying, Verifying, and Establishing Options for Best Management Practices for NOBOB Vessels. Final report to the Great Lakes Protection Fund. www.glerl. noaa.gov/res/Task_rpts/2004/aisreid04-1.html. Shipping Federation of Canada. 2000. Code of Best Practices for Ballast Water Management. Sept. 28. SLSDC. 2007. Seaway Regulations and Rules: Periodic Update, Various Categories. Notice of Proposed Rulemaking. Federal Register, Vol. 72, No. 249, Dec. 31, pp. 74247–74250. U.S. Coast Guard. 2007. 2006 Summary of Great Lakes Ballast Water Management Exams. Ninth District.