Ballast water control: issues & recommendations for protecting the United States' shared Pacific coastline.

• Published date: 22 December 2011
• Author: Thibault, Rebecca M.
• Date: 22 December 2011

I. INTRODUCTION

The biological diversity of sea-life is besieged by the effects of human activity. (1) Under the cover of the ocean, these changes are often concealed from view. However, our inability to readily see these alterations to the marine environment neither masks nor diminishes the insidiousness of this critical environmental problem. Humans have many ways of affecting the biological diversity, or biodiversity, of a marine ecosystem. And the encroachment of aquatic invasive or nonindigenous species, (2) commonly mediated by humans, is "one of the most important agents of ... change to marine biodiversity at the genetic, species, and ecosystem levels." (3) Indeed, it has been noted that this invasion "constitutes one of the four greatest threats to the world's oceans and their biodiversity." (4)

"Biodiversity" describes the biological diversity of genetic, species, and ecological levels in a given ecosystem. (5) The Convention on Biological Diversity (6) and this Note both use the term biodiversity to mean "the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems." (7) Edward O. Wilson, renowned scientist and tireless advocate for the conservation, protection, and study of biodiversity, (8) illustrates the importance of biodiversity by noting that "[e]ach species possesses a unique combination of genetic traits that fits it more or less precisely to a particular part of the environment." (9)

The general threat to biodiversity brought on by the introduction of nonindigenous species is the displacement of one or more native species. Globalization and trade have contributed widely to this displacement. For example, Columbus's landing in 1492 had an especially startling force in the Caribbean and the Americas: the settlers and their living cargo caused changes to entire landscapes, creating fields of new grass species where once there were forests. (10) Indeed, the result of these biological changes has led some biologists to refer to the post-Columbus years as the "Homogenocene" era, a reference to the homogenization of ecosystems "mixing unlike substances to create a uniform blend." Indeed, "[w]ith the Columbian Exchange, places that were once ecologically distinct have become more alike." (11) This occurrence may have multiple effects, including irreparably altering the food chain, significantly changing the ecosystem's functions and capabilities, causing outbreaks of disease, endangering food supplies, and causing severe economic damage. (12)

Currently fueling the threat to marine biodiversity is ballast water discharge, which acts as a conduit for the introduction of aquatic invasive species ("AIS"). (13) Indeed, AIS contamination has already costs thousands of human lives and billions of dollars. (14)

This Note discusses the problems associated with the lack of international standards to control such introduction of invasive species by ballast water discharge. Part II explains the basics of ballast water discharge and illustrates the scope of the problem by highlighting the severe consequences to both economies and public health caused by nonindigenous species. Part III explains the basic ballast water control methods and surveys the response to these problems by both the United States and the International Maritime Organization ("IMO"), a UN specialized agency. Part IV offers some proposals for how the United States might approach a trinational solution and why such a solution may be favorable to waiting for an international solution. Finally, this Note concludes in Part V by summarizing the issues presented and their associated recommendations.

II. BALLAST WATER DISCHARGE: WHAT IT IS AND HOW IT IS CONTROLLED

Ballast water threats to biodiversity will continue as global trade by ship grows. This part defines ballast water discharge and discusses the significant impact it has had to world economics and to global public health.

A. Defining Ballast Water Discharge

Ballast water is an essential component of maintaining a ship's stability while in transit. (15) Special tanks within a ship will either take up or discharge water known as ballast water to compensate for fluctuations in the ship's cargo load. This mechanism keeps the ship at an even keel whether transporting a full cargo load or traveling empty. (16) The amount of ballast water a ship takes on has an inverse relationship to the weight of its cargo: the more cargo, the less ballast; the less cargo, the more ballast. The changes in ship cargo range from a full load to an empty condition. (17) Because additional weight results in additional fuel costs, ship owners will minimize their use of ballast water as much as possible while maintaining the overall safety and efficiency of the journey. (18)

The amount of ballast water a ship needs usually depends on the type of cargo it carries. For example, a crude oil tanker will generally have a full cargo load only until its destination port. Designed strictly for transporting crude oil, the ship must return to its originating port with empty oil tanks because it delivered its cargo; however, the ship will fill its empty ballast water tanks to compensate for the empty oil tanks. (19) In contrast, a container ship transporting various goods might make a transcontinental journey with a full cargo load, then unload some of the cargo at one port destination, proceeding to its next destination with the load's remainder. (20) The ship would take on and release some ballast water to compensate for the changing level of cargo. (21)

During a voyage, the fluctuations in ship cargo result in a changing need for ballast from port to port. Consequently, ballast water exchanges among different ports during a voyage as ships take on ballast water in one port to compensate for unloaded cargo and subsequently discharge it in another port. (22) This continuous exchange sets the stage for the transportation of AIS. (23) Considering the global nature of shipping, this "movement of ballast water by ships appears to be the largest single vector for [AIS] transfer today." (24) Many of the species in ballast water survive the long trips from their home ports, remaining viable and capable of invasion upon release into their new port. (25) The significant impact of ballast water should be controlled to minimize AIS transfer.

B. Scale of the Issue

Understanding the scale of the shipping industry puts into perspective the scope of the problem. One of the biggest transportation methods for international merchandise is the shipping industry (26) with 7579 oceangoing vessels called on U.S. ports 62,747 times in 2010. (27) Eighty percent of world trade by volume is accomplished through maritime transportation. (28) Given this volume, ports and waterways are at particularly high risk of AIS establishments because the frequency of the trips by ships traveling through them results in "repeated releases of ballast water." (29) These waters may come from neighboring ports or from across the globe. For example, more than thirty percent of ships arriving in the ports of the U.S. state of Washington arrived from Asian countries, while approximately forty percent arrived from other U.S. ports. (30)

Further magnifying the problem, AIS introductions are not limited to shipping ports. Rather, even coastal sites not involved in shipping may experience an AIS introduction. Complexities associated with the temporal and physical necessities of ballast water uptake and discharge, (31) along with "[t]he movement and release patterns of ballast water[, assures] ... that no coastal site, whether it receives direct shipping or not, is immune to ballast-mediated introductions" (32) of organisms. In other words, the risks of AIS introductions are not a problem exclusive to the domain of major ports. (33) For example, ships merely traveling along the coastline may be close enough to shore at the time of off-shore uptake and release of ballast water to make the shore susceptible to "natural onshore advection," (34) meaning that the ballast-discharged organisms ride the waves toward the shoreline, nestling into new homes in lagoons, bays, and other coastal locations. (35) Likewise, dispersal of AIS also occurs through natural ocean currents and the tide, carrying AIS from "larger port systems to remote sites all along a coast." (36)

1. Economic Effects

The economic burdens imposed by AIS are not slight. Whether funding eradication efforts, prevention efforts, or simply just population control, "the annual cost to the United States of attempting to control aquatic invaders is about $9 billion," (37) an amount certain to rise.

Take, for example, the havoc a tiny mollusk, the zebra mussel Dreissena polymorpha, continues to wreak across the United States. In 2004, Congressional hearings, prompted by this tiny mollusk's presence in the Great Lakes, considered the spread of AIS brought into the United States via ballast water. Representative John Duncan from Tennessee, a state whose rivers became contaminated with this AIS, did not exaggerate when he characterized the problem as "a very, very expensive [one] that ... is very, very expensive to solve...." (38) As one of the most closely monitored and well-documented introductions of an AIS, the prolifically breeding zebra mussel has successfully invaded the U.S. waters from the Great Lakes to Lake Mead in Nevada. (39) Transported to North America's Lake St. Claire in a transatlantic freighter's ballast water, (40) the zebra mussel wasted no time in colonizing all five of the Great Lakes, as well as the Mississippi, Tennessee, Hudson and Ohio River Basins. (41)

The explosion of the zebra mussel's population caused the invasion and clogging of water intake pipes and water filtration systems for companies using the water...