EPA's Vessel General Permit and Small Vessel General

Median vessel tonnage (53,526 gross tons) is approximately twice that of even the large oil and
gas tankers. While the actual number of large cruise ships seeking coverage under the 2008
VGP is low (only 127 vessels), the number of crew and passengers aboard is relatively high -
approximately 3,500 per vessel. EPA NOI data indicate that 20% of large cruise ships are less
than 5 years old. Because of the large number of crew and passengers living on-board cruise
ships, graywater generation can average nearly 600 m 3 /day (158,500 gal/day). Median ballast
water capacity of large cruise ships vessels is moderate (3,136 m 3 ). A high percentage of large
cruise ships also use AFC. Moreover, since aesthetics are important to the industry, deck
washdowns may be performed more frequently on cruise ships than other types of vessels. The
above factors led EPA to include large cruise ships in its analysis.
Medium Cruise Ships. Medium cruise ships are those ships authorized to carry 100 to 499
passengers for hire and provide overnight accommodations to those passengers. Although only
22 medium cruise ships are included in EPA’s NOI database, these vessels are relatively large,
ranging in size from approximately 1,500 gross tons up to 5,000 gross tons, and have ballast
capacities ranging from approximately 350 to 400 m 3 . Only 14% of these vessels are less than 5
years old. With passenger and crew capacities up to 499 persons, medium cruise ships have the
potential to generate more than 20,000 gallons/day of graywater. Untreated graywater from
medium cruise ships has been shown to contain similar pollutants to those in untreated graywater
discharges from large cruise ships (ADEC 2006, 2007). In addition, most medium cruise ships
use AFC to prevent biofouling of the vessel hull.
Large Ferries. The NOI database includes 118 large ferries, 12 percent of which are less than 5
years old. Large ferries are vessels for hire that are designed to carry passengers and/or vehicles
between two ports, usually in inland, coastal, or nearshore waters. For purposes of the VGP,
large ferries are those ferries authorized to carry a) more than 100 tons of cars, trucks, trains, or
other land-based transportation or b) 250 or more people. Large ferries usually travel the same
route several times a day but do not provide overnight accommodations to their passengers.
Because many ferries can travel the same route several times per day, they can discharge
pollutants from a variety of sources (e.g., graywater, bilgewater, and seawater engine and
exhaust cooling) to same water body. EPA included large ferries in its analysis due to these
potential discharges.
Cargo [Bulk] and Other Carriers. Cargo carriers (e.g., bulk carrier, freighters, roll-on/roll-off,
container ships) comprise the majority of the “Other” vessels classified in the NOI database. The
attributes of this group of vessels are similar to those of the oil and gas tankers in terms of vessel
size (median tonnage equal to approximately 16,000 gross tons) and median ballast water
capacity (10,198 m3). Approximately 61 percent of the owners/operators of these vessels
reported using on-board treatment systems to treat the various waste streams aboard the vessels,
and fewer use AFC. This is the youngest vessel population reporting in the NOI, with 56% of
the vessels less than 5 years old. EPA included cargo carriers in its analysis due to their ballast
water capacity and prevalence at certain ports.
Emergency and Research Vessels. The emergency and research vessels types include
relatively few numbers of vessels and are relatively small in size, ballast capacity, and number of
passengers/crew. Build date data indicate that 16% of research vessels are less than 5 years old
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