A Survey of the Social, Economic, and Environmental Influences and Impacts of Ferry
Systems, with Specific Illustrative Examples from the San Francisco Bay Area
The Society of Naval Architects and Marine Engineers
Telephone: 201-798-4800
SNAME AD HOC PANEL ON FERRY ENVIRONMENTAL IMPACT
Mr. James J. Sweeney, Chairman
Members
Mr. Robert S. Behr
Prepared by the Ad Hoc Ferry Transit Environmental Impact Panel
January 10, 2000
THE SOCIETY OF NAVAL ARCHTECTS AND MARINE ENGINEERS
601 Pavonia Avenue, Suite 400
Jersey City, NJ 07306
Fax: 201-798-4975
Website: http://www.sname.org
Mr. Roger K. Butturini
Prof. Jose Femenia, P.E.
Mr. David A. O’Neil
Prof. Alan L. Rowen
Mr. Matthew Winkler
Mr. William A. Wood
EXECUTIVE SUMMARY
BACKGROUND
As the twentieth century draws to a close, numerous areas in the United States and abroad are giving serious consideration to the creation of new ferry transit systems, frequently involving high speed vessel designs. Public debate on these proposals is proceeding, involving questions of societal, economic, environmental, and safety impacts.
These four aspects of new ferry systems are important subjects that must not be treated lightly. Addressing them properly requires an understanding of many historical, engineering, regulatory, and scientific subjects beyond the knowledge and experience of the average ”man on the street”, who is generally more familiar with transportation by land vehicles. The global potential of new ferry systems mandates clear and definitive answers.
On September 29, 1999 the Technical & Research Steering Committee of the Society of Naval Architects and Marine Engineers created an Ad-Hoc Panel to survey the situation and prepare this report. The Ad-Hoc panel is chiefly comprised of members of the Ship Technical Operation Committee and the Ships’ Machinery Committee, and is chaired by an individual with forty years of first hand experience commuting by transit ferry, bus, train, and auto in the San Francisco Bay Area.
PURPOSE AND CONTENTS
This report briefly defines and clarifies essential issues of ferry system performance, economic, and societal impact, and describes the technical rationale and operating discipline required to ensure that new ferry systems achieve their intended purposes in a thoroughly safe and environmentally acceptable manner.
The report has been prepared in two parts. The first part addresses the crucial issues in a generic fashion, referring to specifics when required to illustrate points with well-documented examples. The second part reviews historical and contemporary facts of specific San Francisco Bay transit alternatives in conjunction with reasonable projections of future conditions, in order to complete the presentation. The Society of Naval Architects and Marine Engineers sincerely wishes that these contents will be duly noted and put to good use.
IMPACTS OF FERRY TRANSIT SYSTEMS ON SOCIETY, THE ENVIRONMENT, AND PUBLIC SAFETY
HISTORY AND SOCIAL/ECONOMIC IMPACT OF UNITED STATES FERRY TRANSIT SYSTEMS
Mankind has utilized watercraft to link shoreline communities and commerce since time immemorial. For most of human history this activity proceeded on an irregular basis, with trips accomplished on an as-needed basis under human paddle or oar, and sail power. The advent of practical engine-powered vessels in the early 19th century enabled operators to begin offering scheduled service, and the modern concept of ferryboats began. Engine powered ferries have performed vital transportation duties in all major ports of the globe, accumulating a remarkable record of reliable, economic, safe and efficient service. In the United States, large ferry systems have been particularly important to commerce, communication and recreation in New York Harbor, Puget Sound, and (excepting a period from the late 1950’s until the mid 1970’s) San Francisco Bay. Some representative numbers on ferry operations in differing geographic areas are shown below.
| Location | Population | Ferry Terminals | Ferry Routes | Riders per Year |
| Sidney | 3.3 million | 29 | 10 | 13 million |
| Hong Kong | 6.5 million | 19 | 19 | 30 million |
| Seattle | 2.9 million | 20 | 10 | 25 million |
|
San Francisco Bay Area |
6.6 million | 9 | 6 | 3.5 million |
Beginning in the mid 19th century important ferry routes were linked to rail and omnibus transit systems. These formed an unsurpassed network of public transportation for many cities of the United States through the first half of the 20th century. As one example, San Francisco ferry and streetcar routes of the 1930’s served over 250,000 passengers a day, with 340 ferry arrivals and departures connecting with streetcars departing every twenty seconds. The time required to cross San Francisco Bay on ferries of that period chiefly depended upon the distance of the particular route, such as 32 minutes to San Francisco from Sausalito and 38 minutes to San Francisco from Oakland. This compares favorably with today’s peak highway commute times of 32 minutes and one hour, respectively, over the same routes.
The majority of American ferryboats were built as the lower cost alternative to bridges or tunnels (underwater tubes) across rivers and harbors. Continued economic and population growth in large metropolitan areas led to massive public works, including bridges and tunnels, particularly during the great depression. America’s post-war love affair with the automobile, the ascendancy of new suburban communities, and construction of the federal interstate highway system in the 1950’s completed the transition, terminating numerous ferry routes and either eliminating or decimating their connecting rail and bus transit systems by the end of the 1950’s.
During the 1960’s inland ferry operations serving metropolitan areas in the United States were limited to only a few remaining locations with the right mix of distance and high passenger patronage, such as the very extensive Washington State Ferry system in Puget Sound and the popular Staten Island ferry in New York harbor.
Rekindled Interest in Public Transit
In the 1960’s and ‘70’s the American automobile fell victim to its own success. Ever increasing traffic congestion, particularly during the two daily peak commute times; the growing social, environmental, and fiscal costs of more freeway lanes, overpasses, bridges, tunnels, and parking facilities; and gasoline shortages during the 1970’s cumulatively demonstrated that the time had come to reinvest in public transit. All levels of government began expanding existing public transportation systems or building new ones, primarily bus and light rail lines connecting suburbs and cities.
At the dawn of the new millennium the highways and streets of urban areas in the United States have already reached the point of traffic saturation. Projections of increased population and economic growth indicate that pressure on transportation networks is bound to increase. It is clear that unless alternatives can be found the economic vitality and quality of life in these areas will deteriorate.
Buses
It became evident during the 1970’s that while buses are the most immediately affordable public alternative to the automobile, buses share streets and highways with autos and trucks and are equally susceptible to traffic congestion and delays. A majority of commuters, particularly in car-oriented California, would not and will not abandon their autos to ride a bus that is less convenient and no faster than an automobile. A better and more acceptable alternative is needed.
Light Rail
New rail systems have the advantages of potentially greater passenger capacity and smaller operating manpower per passenger than buses. The primary advantage of rail over buses and autos is, however, a separate right of way independent of highway congestion. Unfortunately, a new independent right of way in metropolitan areas demands the acquisition and demolition of great stretches of expensive real estate. Most abandoned rail right of way in metropolitan areas was converted to alternate uses long ago. New rail transit is therefore intensely disruptive to communities and very costly to construct, assuming that a new right of way can even be found. It usually cannot be justified without solid projections of great numbers of passengers. In recent years new light rail systems have been successfully completed to serve major metropolitan areas of the U.S.A., notably Washington, D.C., inland Los Angeles, California, and San Jose, California.
When the difficulty and/or cost of new rail are prohibitive, an alternative must be found.
Automobiles
Automobiles have made progress as commute vehicles but much of it is moot. Today’s autos are safer, more comfortable, more fuel efficient, and individually less polluting than their counterparts of previous years, but are also more costly to own, operate, and park. Special high density (ride pool) freeway lanes and the use of rideshare vans for groups of commuters enable better utilization of highway and parking space, but remain the exception, rather than the rule of highway commuters. The increasing popularity of light trucks and sport utility vehicles has reversed the fleet trend to greater fuel economy, increased average emissions per passenger mile, and exacerbated congestion and driving stress for those using automobiles. Ultimately, the problem with commuting by private vehicle is that there are already too many people doing the same thing, and their numbers keep growing.
The overwhelming numbers of automotive vehicles of all kinds and the heavy reliance Americans place upon them for daily transportation needs have made automotive exhaust emissions by far the largest component of air pollution and global warming “greenhouse gases” generated in the United States.
Water Crossing Structures
Rail or highway routes across bodies of water require new bridges or underwater tubes, the expense of which is often prohibitive. Civil engineering safety requirements to resist seismic forces compound the costs of such works in regions susceptible to major earthquakes, such as California.
Because of the enormously high construction and environmental costs of bridges, underwater tubes, and tunnels, their sites and numbers are limited. Their locations are of necessity compromises compared to the direct point-to-point travel possible by water transit between numerous shoreline trip origins and destinations. Highway and rail travel must be diverted from the shortest, most direct route across the water in order to allow the limited number of bridges, underwater tubes, and tunnels to serve as many different land approaches as possible. More direct and less costly crossing alternatives would better serve the public.
Declining Land Transit Speeds
Despite massive public spending over the past 65 years for new bridges, tunnels, underwater tubes, highways, buses, and rail lines, these works have produced few, if any, shortened vehicular commute times. On the contrary, average vehicle speeds on freeways in metropolitan areas have been declining steadily and are currently in the order of 12 to 17 miles per hour during peak commute hours. This represents a tremendous waste of human time and non-renewable energy resources (primarily gasoline and diesel oil). It burdens the atmosphere with air pollution, is an impediment to business efficiency, and constitutes a daily detriment to the quality of American life.
Commuting by highway today has been described as having the aspects of a disaster movie: Daily accidents, sirens, helicopters, radio broadcast updates on conditions every ten minutes, and incidents of “road-rage”.
Better alternatives are needed and are being actively pursued. The most promising, for areas with adjacent navigable waters, are ferries.
A New Role for Ferries
The foregoing factors have re-awakened interest in ferry systems, not merely in the traditional role as links between existing land-based transit systems, but as independent entities paralleling and competing with shoreline highways, bridges, and transit. As the twentieth century drew to a close, ferry systems began to be recognized as the only viable alternative left.
Recent developments in high-speed vessel technology have increased the options available to transit system planners and enhanced the growing awareness of ferry advantages. (NOTE: The generally accepted definitions for rapid ferries are as follows: “Fast ferries” achieve speeds in excess of 25 knots, or about 29 miles per hour. “High-speed” ferries achieve speeds in excess of 35 knots, or about 40 miles per hour.) Actual service results of high-speed vessels from Australia, Europe, Asia, and in such North American locations as the New York area, San Francisco Bay, and Puget Sound have confirmed that the concept, when properly implemented, has the ability to deliver long-sought results.
Whether “fast” or “slow”, all ferries have the potential to offer commuters, commerce, and local travelers reduced transit times, safe and enjoyable trips on an unimpeded zero cost “right of way”, at modest cost and with minimal disruption to the community and the environment.
However, some new ferry service proposals have encountered resistance. One objection raised is that the proposed ferries will only serve limited routes. While it is acknowledged that specific new routes will not be able to serve every community, it is also clear that commuters from and visitors to shoreline communities will benefit greatly. As these people are induced to use ferries and leave their automobiles behind, highway, street and parking congestion will diminish and air quality will improve. Every commuter and resident of the affected region will benefit. Another counterpoint to this argument is that many inland communities have been provided bus, rail, and highway commute systems that do not or cannot serve shoreline destinations. Simple justice suggests that each community is entitled to capitalize on its geographic advantages, particularly when it serves the general good.
Environmental impact and safety questions have also been raised. These issues are readily manageable and constitute less risk to the natural environment and population than posed by land transportation alternatives. Environmental impact and safety are reviewed in detail in the remainder of this report.
A Basic Transit Principle for the 21st Century
It is very important to bear in mind that the primary objective to be achieved by any transit system is the movement of people (and sometimes goods) at the lowest sum of costs to society and the environment. While economic and environmentally benign ferry systems can be built and operated, that is not a reason why they should be built and operated. The fact of the matter is that densely developed metropolitan regions such as New York and San Francisco simply cannot bear any more vehicular traffic. The primary justification for new ferry systems in such areas is to mitigate vehicular traffic on already overloaded bridges and streets, and to alleviate pressure on inner city parking resources.
In that respect, California’s Golden Gate Bridge, Highway, and Transportation District has shown the way. The undeniable proof of success for the Golden Gate ferry fleet is overflowing commuter parking lots north of San Francisco, and 2,200 fewer automobiles passing over the Golden Gate Bridge and into San Francisco each commute day.
If history teaches anything, it is that ferry systems provide unquestionable benefits to commerce and society that cannot be economically or practically duplicated by land transportation alternatives.
ENVIRONMENTAL IMPACTS OF FERRY SYSTEMS
There are several important environmental issues related to ferry systems and no discussion of new ferry proposals would be complete without addressing each of these in turn. While a survey report of this type cannot provide the in-depth analysis required to effectively deal with every route-specific question, the following general description of potential problems and solutions should provide sufficient information to allay speculative concerns.
Impact on Wetlands, Habitat, and Wildlife
The action plan for a recently proposed expanded ferry system in San Francisco Bay (reference 1) specifically includes the following performance objective:
“Protect Environmental Quality
Terminals will be sited and the system will be operated to: (a) avoid any significant impacts on existing wetlands, habitat, and wildlife; (b) assure no net loss of wetlands, habitat, and wildlife: (c) support and promote the intent of the Bay Area Wetlands Goals project; and (d) expand the total acreage of wetlands and habitat in the ecosystem should mitigation become an appropriate remedy as a result of an environmental assessment process.” This is an excellent statement of policy that addresses one of the most obvious and significant problems of ferry system development: the siting of shoreline terminals, parking, and infrastructure essential to support ferry operations.
The following example of the importance of proper environmental policy statements is illustrative. During preliminary evaluation of the recently proposed San Francisco Bay ferry expansion plan, it was discovered that one new ferry terminal, projected to account for roughly one fifth of the entire system’s passenger patronage, could not be sited without adversely impacting adjoining wetlands. Mitigation was considered but rejected as practically pointless due to the environmental significance of the region. Further consideration of ferry operations in that area was immediately terminated.
Dredging
It is unlikely that dredging will play any significant role in future transit ferry proposals in the United States. The costs of sampling, analysis, and disposal of dredging spoils have become so prohibitive that very few, if any, American ferry systems can afford to support them. Future ferry terminals will only be sited in locations where dredging is already being accomplished for other purposes (such as deep-sea vessel traffic) or where the water is of sufficient depth to sustain ferry operations without dredging.
This is not to say that shallow waters invariably preclude ferry operations. Special shallow draft ferry designs may permit operations in regions not practical for deeper draft vessels. The situation must simply be evaluated on a case-by-case basis.
Impact on Native Species
The long history of operations clearly establishes that ferries have very little if any adverse impact on aquatic mammals, birds, fish, crustaceans, mollusks, or lower animal species, nor on species of aquatic plant life. A ferry rider on San Francisco Bay is witness to a daily panorama of contented sea lions cavorting or basking on buoys, of soaring gulls and pelicans, and of an occasional whale or shark swimming nearby. The contrast with an automobile or bus rider’s view of “road kill” (deer, raccoon, opossum, skunk, dog, and cat) on local highways is too painfully obvious to merit further discussion.
The fact of the matter is that the primary environmental threats to aquatic species are land vehicle operations and agriculture. (See discussion of Water Pollution.)
Ferry Wakes
The wake, or wash, behind a vessel can present serious problems. There are in fact instances where high-speed vessels were placed into service without consideration of wake impact and shoreline damage resulted. Such cases are not only regrettable, but also entirely avoidable if prudent judgment and modern technology are applied in the initial route selection, vessel design, and operating scenario planning process.
Wake Impact
Vessel wakes can be potentially harmful to shallow water plant and animal life at the lower end of the aquatic food chain and, to a lesser extent, nesting birds along shorelines. Previous experience has clearly demonstrated that a ferry transit vessel with even a potentially destructive wake will not be tolerated in closed shallow waters, particularly adjacent to populated or environmentally sensitive areas. There are various methods in use and under development around the world to define what is and what is not an environmentally acceptable vessel wake. Perhaps the simplest and most readily understood is that shoreline waves generated by passing vessels should not significantly exceed the size and energy of naturally occurring waves in the area under consideration. Allowing for seasonal weather variations and the impacts of tidal action and currents, this is a proper, conservative yardstick.
Managing Vessel Wakes to Prevent Environmental Harm
The size and energy of any particular vessel wake will vary with numerous factors, most of which are manageable with today’s technology: hull length, beam, draft, and shape; speed; vessel type (e.g., monohull or multihull, displacement, surface piercing, or planing); and harbor features (shoreline distance, shoreline composition (e.g., rocky, manmade rip-rap, or soft sediment), water depth, bottom contours), etc. While anecdotal and empirical data exists on the wakes of specific vessels under varying conditions, the subject has not been studied in rigorous detail, and standard engineering design techniques for wake management do not exist beyond reference to historical precedents or extensive testing. As a result, vessel designs have occasionally been promoted with low wake claims that proved to be unrealistic. A research and development program to establish wake design standards and improve the predictability of new vessel wakes has been proposed and is actively being promoted within the Society of Naval Architects and Marine Engineers.
The first consideration in preventing harmful wakes is to ensure that the vessel design incorporates proven (by either historically or rigorous design analysis) low wake features. The next consideration is that the speed schedule selected for the proposed route be suited to the intended operating region.
Vessel Design and Wake Generation
It behooves any ferry system planner to employ the services of a qualified naval architect and marine engineering design agent to ensure that the vessel design and speed schedule selected for the proposed route result in an acceptable wake. Reliable technical information is available on previous and existing vessels capable of good speed with minimal wakes. In addition novel designs continue to be developed, particularly for high-speed vessels, expanding the scope of possible solutions. Where the fast ferry designer was once limited to consideration of monohulls, hyrofoils, air-cushion vessels, or catamarans, new alternatives such as surface-piercing multihull designs and pentahulls continue to be developed and even patented. As new designs are transformed into actual vessels and subjected to full scale testing, more information accumulates and the scope of alternatives available to ferry transit planners expands. The chief caveat is that the ferry transit system manager must not forge ahead with a preconceived notion of what the future vessel will be like. Feasible options must be left open to the vessel designer in order to avoid construction of a ferry that will not be allowed to operate as intended.
Vessel Speed and Wake Generation
The basic question of speed is a vital consideration in the optimization of every ferry system plan. Many routes are simply too short to justify investment in the high horsepower engines and/or specialized hulls required to achieve high speed. In other cases, the required route may be too close to sensitive shorelines to permit, as an example, some of the current fast catamaran designs. The wake problem on such routes can be dismissed with inexpensive and modestly powered conventional vessel designs. Very high speeds should not be considered for short or environmentally sensitive shoal water routes.
Even on routes where shoal waters and sensitive shorelines exist, the ferry planner has the option to operate fast vessels at reduced speed in those areas and then accelerate to higher speeds in open waters where there is no risk. This is exactly the choice made for California’s Golden Gate Larkspur ferries: restricted speed within the Larkspur channel, and full speed on the open waters of San Francisco Bay. Safety is of paramount importance in all maritime operations.
An Unexpected Consequence of Ferry Wakes
Articles have recently been published in the media describing dangerous ferry wakes, particularly from fast vessels operating in Scandinavian coastal waters. Ferry system opponents have capitalized on these reports to raise grave warnings about hazards to swimmers and recreational boaters. While the reports of risks are real, it does not follow that this hazard is an inevitable consequence of every fast ferry operation. The proof of the matter is demonstrated by the following contrasting example. An unanticipated but delightful consequence of California’s Golden Gate ferry operations has been the enthusiastic response of local windsurfers, who regularly pursue their sport in the benign (i.e. small, but steady) ferry wakes of the Larkspur channel approach, much to their satisfaction and the amusement of commuters, ferry officers, and crew. Chasing ferries by surfboard has been a safe and popular activity for roughly twenty years, with no accidents or injuries to participants. In addition, several years of fast ferry operations on various San Francisco Bay routes, often crowded with recreational boaters, have produced no adverse incidents.
In short, the issue of wakes, particularly for high-speed vessels, is significant. However, it can (and must) be managed professionally, like all the other requirements that go into the optimization process for new vessel design and operation.
Water Pollution
Ferry refueling and other operations involving the handling of potentially harmful products and materials are carried out under strict U.S. Coast Guard and Federal Environmental Protection Agency regulations prohibiting water pollution. American regulatory bodies treat large vessels, including transit ferries, like major industrial facilities sited on land. All were recognized years ago as potential “point specific” sources of water pollution. Highly detailed procedures and engineering requirements were then written into public law to prohibit harmful spills and discharges. Severe monetary fines and even criminal penalties are mandated for offenses. This program has been extremely effective. The long sought era of “zero discharge” is being achieved. It is also noteworthy that, in addition to federal regulations, industrial and marine facilities and operations are subject to the state and local environmental regulations imposed by water quality boards, departments of fish and game, etc.
The success in preventing water pollution from “point specific” sources such as ferries is in marked contrast to America’s failure to control “non point specific” sources of water pollution. Virtually all toxic pollutants now entering navigable waters of the United States originate ashore, primarily from vehicular lubricant leaks, antifreeze spills, and other byproducts of automotive operations on the streets and highways of adjoining or nearby communities, but also from agricultural pesticides, livestock waste, and fertilizers. All these environmentally harmful materials are continuously entering rivers and harbors via shoreline grades, sewers, and storm drains.
Air Pollution from Engine Emissions
Modern ferry engines generate exhaust emissions comparable to that of their counterparts in other transportation modes. Diesel powered ferries generate emissions similar to diesel powered trucks, buses, and locomotives. Gas turbine powered ferries generate emissions comparable to those of jet aircraft, and can be readily modified to produce even lower oxides of nitrogen (NOx) emissions than aircraft engines. As explained above in regard to water pollution, government regulatory agencies exist to enforce air pollution limits on vessels. Plumes of visible smoke (particulates) that exceed a few seconds of duration are severely fined. Additional Federal Environmental Protection Agency regulations and state regulations from agencies such as the California Air Resources Board are now under development and are planned to be imposed in stages over the coming decade.
Engine emissions of concern to human health and the environment include NOx and sulfur oxides (SOx), both of which are serious constituents of smog; dioxins; global warming (greenhouse effect) gases; and particulate matter (soot). Many of these harmful products of combustion have been mitigated, particularly over the past thirty years, by advances in engine design and combustion technology, fuel refining, and the practical application of post-combustion equipment such as catalytic converters for exhaust systems. Progress continues to be made in this field of technology, as described below.
Emission Reduction Developments in Fuels
The generation of SOx from diesel engines has been significantly reduced by the introduction of special refining processes to produce low sulfur diesel fuel. This technology has proven so effective that diesel exhaust emissions of SOx are no longer considered environmentally significant when low sulfur fuel is used.
Compressed natural gas (CNG) shows great promise as the most environmentally benign fuel for future internal combustion engines. It can probably be utilized in buses, locomotives, and ferry vessel engines with identical beneficial impact on exhaust emissions. Experimental programs have already been initiated to demonstrate the practical feasibility of both CNG powered buses and vessels and to develop specifications for safe fuel storage, handling, and replenishment procedures. In fact, because of their smaller number, larger size, repetitive routes, and simpler terminal fueling facilities, ferries may prove to be better candidates for CNG fuel than bus fleets.
A natural gas powered ferry is currently being successfully operated by Tidewater Regional Transit in Norfolk, VA (reference 2). Fraser River ferries in British Columbia have been operating on CNG since the early 1980’s. In response to environmental quality concerns, construction of three new large ferries powered by liquefied natural gas (LNG) has begun in Norway (reference 3). Additionally, the environmental impact of three proposed natural gas powered ferries was considered in a May 1999 study in Boston, MA (reference 4). The study concluded that the proposed ferries would reduce NOx by 8 tons per year, SOx by 7.3 tons per year, and particulate matter by 1 ton per year compared to the emissions of automobiles and other transportation modes the ferries would replace. Natural gas also shows great promise as the most likely source of hydrogen for the emerging use of fuel cell technology in the marine industry.
Marine Engine Design and Manufacture
The designers and manufacturers of the diesel engines and gas turbines now used in marine application work for the same companies, and in many cases are the very same people who make engines used in land and aviation applications: for locomotives, trucks, buses, automobiles, construction and farm machinery, stationary power generating stations, and for aircraft. They can apply any of the technological innovations used on land and aircraft engines to marine engines. In fact, because marine engines are fewer in number but generally larger and their installations more capital intensive, there is often more practical, economic, and environmental incentive to install upgrades on marine engines than on the far more numerous but usually smaller engines used in land vehicles and aircraft. As one example, a typical modern marine diesel engine comes with an electronic ignition control system that can be set to automatically produce either optimum fuel economy or minimum emissions. This kind of technology was not available a few years ago and, if history teaches anything, it is clear that advances in fuel combustion and emissions control technology by engine manufacturers, government research, and the petroleum industry will continue.
Where gas turbine engines are an appropriate choice for a marine application, a water injection device can readily be added to the engine fuel system to dramatically reduce exhaust emissions.
Marine engine manufacturers support progress in exhaust emissions technology as a simple matter of good business. With today’s global economy, the marine engine industry has plenty of competitive, economic, and social incentives to meet future Environmental Protection Agency emission standards, particularly on harbor and inland waterway vessels, such as ferryboats.
Engine Exhaust Emission Comparisons
Comparing the exhaust emissions of competing transportation modes is not a simple job. A great deal of engineering effort is required to either obtain highly reliable “real world” data or a combination of many verifiable laboratory tests and factually based adjustment factors. Unless the effort is comprehensive and professional, the results obtained will bear no resemblance to reality and will therefore be useless. If published, such results effectively constitute disinformation that must be exposed and refuted.
Previous attempts to compare published emissions data of ferry vessels to automobiles and buses suffer from two crucial defects. First, since marine diesel engines have to date been exempt from detailed U. S. and State Environmental Protection Agency emissions standards (and acceptance testing) there is virtually no published information available on their emissions. Second, published results for automotive and bus engines, obtained under steady load test conditions, are totally unrepresentative of the engine emissions actually generated under highly congested “stop and go” freeway and street commuting conditions. It is therefore impossible to precisely assess the emissions of one mode of transportation versus another with such statistics. The best way to accomplish this goal would be to conduct extensive field testing. The U.S. Department of Transportation and the Society of Naval Architects and Marine Engineers both acknowledge the problem and are currently proposing projects to provide reliable and representative data. In the meanwhile, reasonable engineering estimates of emissions can be developed from other sources.
One respected engineering analysis, enclosed with this report, was completed in May of 1999. It concluded that, on a per passenger basis, existing automobiles generate approximately ten times the amount of toxic and global warming carbon monoxide (CO) and four times the unburned hydrocarbons (HC, a smog component) of an existing diesel engine powered fast ferry, while the ferry generates three times the smog contributing nitrogen oxides (NOx) and ten times the particulate matter (PM) of the automobiles. When all components of engine exhaust emissions are weighed, the harmful emissions of the automobiles summed to roughly two and a half times that of the fast ferry.
It is important to bear in mind that neither future vehicle nor vessel designs are limited to existing propulsion system technology. Use of gas turbine, hybrid gas turbine/diesel engine, and fuel cell propulsion plants all offer significant reductions in NOx and PM emissions.
The primary considerations involved in valid engine emission comparisons per passenger transported are explained in greater detail in Part II of this report.
Marine Diesel Engines
The vast majority of modern ferry vessels are powered by marine diesel engines. While the manufacturers of these engines have been exempt from federal emissions standards, they have nevertheless continued to reduce engine emissions by ongoing advances in combustion technology. Mechanical fuel injection control systems, which were the historical standard, were recently replaced by electronic injection control systems that enable dramatic reductions in NOx emissions at all power generation levels. Comparable advances in combustion chamber and fuel injector design have enabled lower fuel consumption and reduced greenhouse gas emissions per unit of power generated. Engines meeting the Environmental Protection Agency proposed tier II standards are currently undergoing testing and will be available for sale when those standards are adopted.
Developments in Alternative Vessel Propulsion Systems
New technology and new applications of proven technology continue to impact both the marine and land transportation industries. Comparisons between the future engines of ferries and over the road vehicles will err if the assumption is made that diesel engines are the only practical choice for ferries. This assumption fails to take into consideration some of the inherent advantages of ferry design. Weight, volume, fuel consumption, and operational profile are important considerations in all transportation modes, but the dimensions and operating characteristics of ferries allow a much greater flexibility in the choice of propulsion and fuel system alternatives. In other words, ferries are generally better suited to alternative fuels and engines than other transportation modes. Three promising types of vessel propulsion merit mention:
Gas turbines
Gas turbines continue to gain acceptance for marine propulsion units on the basis of both high power to weight ratio and low emissions. U. S. Navy tests have established that marine gas turbine exhaust emissions are substantially lower in CO and that the NOx produced is an order of magnitude lower than that of medium speed diesel engines (reference 5). Additional combustion modification, such as by water injection, can further diminish gas turbine emissions.
Fuel Cells
Independent studies by both the U.S. Navy and U.S. Coast Guard (references 6 and 7) have concluded that vessel propulsion by fuel cells reduces fuel consumption and maintenance costs and lowers exhaust emissions to “vanishingly small” levels compared to traditional Carnot (heat cycle) engines. The chief drawback of fuel cell technology at this time is very high initial cost. It is considered likely that fuel cells will become more affordable in the future as the concept gains acceptance and enters the industrial (mass) production phase. The U.S. Department of Energy, U.S. Navy, U.S. Coast Guard, National Atmospheric and Oceanographic Administration, and other U.S. government agencies have ongoing programs evaluating fuel cell technology and applications to marine propulsion.
Ferry Noise
Ferry engines generate noise like all other engines. Generally speaking, ferry engines are comparable in noise to, or at least no worse than, trucks, buses, locomotives and aircraft. However, vessels have much more space and weight capacity available for noise abatement hardware than, say, locomotives or aircraft with similar sized engines, or several buses with an equivalent total horsepower.
Engine noise level management, like wake management, is a consequence of vessel design and operating procedures. Modern noise abatement technology allows a wide variety of vessel options to achieve specified limits, and must be applied during the design optimization process to achieve satisfactory results. Recent high-speed ferry designs have been particularly successful in this regard, as simply one more important element of passenger comfort.
Ferry Safety
Transportation safety issues are constantly brought to public attention when airplane crashes, train wrecks, and the far more frequent street and highway accidents occur. Fortunately, ferry operations have an unsurpassed safety record, as exemplified by 150 years of service on San Francisco Bay. Well over a billion passengers have traveled on Bay Area ferries since the California Gold Rush. All significant ferry accidents and all deaths occurred between 1859 and 1928. The sum fatality rate for Bay Area ferry passengers is less than one millionth of one percent (reference 7). No other transportation mode remotely approaches this kind of safety record.
Much of the modern fleet of ferries now in service on San Francisco Bay has been operating for twenty-four years, continuing a proud tradition of safe and reliable public service. Even their most vocal opponents concede that ferries provide both commuters and casual travelers a scenic and thoroughly delightful respite from highway traffic, with its daily exposure to tragic and sometimes- fatal accidents, toxic exhaust fumes, and the growing intensity and frequency of “road rage” incidents.
Ferry Personnel and Equipment
Ferry officers take great care to avoid adverse incidents when encountering other vessels or when operating in times of restricted visibility, such as dense fog. Sophisticated (aircraft derived) electronic navigation and piloting aids greatly contribute to the modern ferry officer’s knowledge of vessel position and harbor traffic regardless of weather. Professional mariners will always slow a vessel to a safe speed and commence sounding the ship’s whistle, if necessary, just as they have done for generations. When high speed/fast ferry operations are involved, special training (in navigation, vessel maintenance, fueling, emergency procedures, and contingency planning) must be provided to ensure that officers are fully cognizant of the wake issue and that wake controls are exercised.
Safety Regulations
All existing and planned ferries serving in the United States must meet U. S. Coast Guard safety regulations far exceeding anything aboard vessels in service prior to and during the 1960’s. Fire protection, watertight integrity, hull stability, navigation and piloting, crew training, certification, and licensing, as well as lifesaving equipment have all benefited from over a century of applied maritime experience and relentless advances in technology and materials.
Navigation and Piloting Systems
The navigation and piloting equipment aboard the modern fast ferry M/V DEL NORTE illustrate this point. In addition to the traditional U.S. Coast Guard approved magnetic compass, bell, whistle, navigation lights, navigation clock, clinometers, and searchlight this vessel is equipped with two KVH Azimuth 314AC Fluxgate compasses, two radar units, a radiotelephone, windshield washers, windshield wipers, and a differential Global Positioning System (GPS) which interfaces with the speed, compass heading, and radar displays. The control console is fitted with anti-glare shields to prevent sunlight from obscuring the display faces. All instruments are equipped with infinitely variable dimmer controls for night operation and to minimize back lighting on windows. The vessel is further equipped with floodlights to support line handling, entry and egress through boarding stations, and life raft launching during periods of reduced visibility.
Besides the equipment aboard the ferry all ship activity within San Francisco Bay is under the management of the U.S. Coast Guard Vessel Traffic Control system. This centralized traffic and communication system has the sole purpose of monitoring vessel movements and preventing accidents, a job that has been successfully accomplished since the system was set up many years ago.
It is also noteworthy that a recent Formal Safety Assessment for high-speed catamaran ferries compared actual operating experience with previous projections of risk. The accident categories covered included collisions with other vessels, contact with other objects (buoys, piers, groundings, etc.), fire, and loss of hull integrity. The study concluded that the actual safety of high-speed catamaran ferries is five times better than originally estimated during initial projections (reference 9).
To summarize, there never has been a safer means of transportation in the United States of America than ferry transit.
A COMPARISON OF TRANSIT ALTERNATIVES USING THE SAN FRANCISCO BAY AREA TO ILLUSTRATE SPECIFICS
Earthquakes, Geography, and Land Use
San Francisco and its surrounding communities have had particularly compelling experiences with ferries. During the great earthquake and fire of 1906 and again during the Loma Prieta earthquake of 1989 (which collapsed a section of the San Francisco-Oakland Bay Bridge, destroyed massive portions of local freeways, and shut down light rail and highway transit systems), all ferryboats and terminal facilities remained unaffected, performing essential transportation duties without interruption.
Seismic risks associated with major traffic arteries such as freeways, bridges, tunnels, railroad rights of way, and underwater tubes are a recognized fact of life in California. The cost of upgrading existing infrastructure is immense. The cost of new infrastructure is often prohibitive.
Bay Area residents currently lose 90,000 hours each commute day to street and highway traffic congestion. Despite these adversities, the economy of the Bay Area, like that of other large metropolitan regions, continues to expand. In 1999 the California Department of Transportation projected that vehicular traffic will increase 250% in the next twenty years.
The basic aspects of the geography of the area strongly suggest ferries as the most logical and environmentally acceptable solution to impending gridlock. Numerous cities and important sports arenas, cultural centers, and recreational attractions adjoin the irregular shoreline of San Francisco Bay. Direct passage between these destinations by watercraft only requires the construction of terminal/parking facilities and new vessels to serve the routes.
Comparative Costs
The costs and land required for ferry facilities and vessels are modest compared to the alternative requirements of increased highway, rail, bridge, and/or underwater tubes. Expanding the existing Bay Area ferry system to serve twenty to thirty more terminals would cost roughly $500,000,000 to $2,000,000,000, depending upon the scope of the program and features of the new vessels and terminals. By comparison, new highway capacity in the San Francisco Bay area is priced at a minimum of $32,000,000 per mile and new light rail costs $70,000,000 per mile. The public investment in a single freeway interchange, at $100,000,000 to $300,000,000 could easily fund half of the entire ferry program. All of these costs, staggering as they are, pale in comparison to the expense of additional Bay crossings by bridge or underwater tube.
The total price of new highway or rail solutions would probably exceed the cost of the proposed ferry expansion plan by six to ten times, and would subject hundreds of route miles of productive real estate to transportation right of way.
Comparing Alternative Engine Emissions on One Commute
One question raised by concerned environmentalists has been the issue of air pollution by ferries, compared to the emissions generated by competing highway transit modes for equal numbers of passenger miles.
As previously mentioned, appropriate data and reasonable assumptions are absolutely essential to any comparison of transportation alternatives. In the discussion that follows, each significant parameter is named and its factual basis explained in order to ensure that only valid statistics are selected for engine emission comparisons. The route and transit modes selected by the environmentalists for discussion purposes are the Golden Gate Bridge, Highway & Transportation District’s Larkspur to San Francisco fast ferry M/V DEL NORTE, its competing transit bus lines, and automobiles operating on the same highway and street system, between the town of Larkspur, in Marin County, and downtown San Francisco. The same route and transit modes will be used in the comparison that follows. One noteworthy aspect of the comparison is that all engines used in the buses and ferry under consideration happen to be made by the same manufacturer, Detroit Diesel.
Engine Exhaust Emissions
The emissions of engines vary greatly depending upon the type of fuel being consumed, the type of engine, engine design details, the degree to which the engine is being maintained, and the condition (load profile) under which the engine is being operated (cold start, idle, full vs. partial load, steady load, or continuously fluctuating load). Any analysis that purports to compare engine emissions from alternative transit modes must address all these vital issues or it will draw mistaken conclusions.
Past, Present, and Future Fuel Types and Emissions
The highly sophisticated distillate fuels used by ferries, buses, automobiles, and trucks today are virtually synthetic blends of petroleum derivatives and additives, a far cry from the simple fuels used before the 1970’s. Much of the progress in fuel refining and blending has been driven by the need to reduce harmful engine exhaust emissions. The State of California has been a leader in promoting this goal. All engine types being compared for exhaust emissions generated by ferryboats, buses, and automobiles benefit from this progress. By the same token, future developments in cleaner burning fuels or energy generation by alternative means such as fuel cells will likely be applicable to both ferryboats and land vehicles. Fuel alternatives and fuel refining emissions reduction technology are the same for both land and ferry applications in California and have little if any impact on comparative exhaust emissions.
Emissions Rates
Internal combustion engines generate more emissions when they are cold (following startup) than when they are fully warmed up. Cold starting, therefore, represents one aspect of total emissions that needs to be taken into consideration. On trips in excess of twenty minutes duration, total engine exhaust emissions start to become progressively proportional to the total quantity of fuel consumed. The longer the trip, the more this will hold true, as the initially high emissions generated during cold starting become less significant to the total.
The standard units used to rate engines on exhaust emissions in California are grams of emissions per pound of fuel burned. All other things being equal, anything that increases an engine’s fuel consumption (longer period of operation or higher level of power output, as when accelerating or climbing grades) increases total emissions.
Assessing Automobile Passenger Miles and Emissions
The automobile is a useful baseline vehicle for comparison purposes. Commuter autos are highly convenient because they provide essentially door-to-door service with little or no side trips other than to refuel or handle occasional errands. The average number of auto passengers on the route being considered is 1.15 per automobile.
The automobile exhaust emission factor to be used in the comparison is clearly a critical question. The use of unadjusted automotive fleet average emissions (F.A.E.) data is totally inadequate on a number of important counts:
1. F.A.E. represent the emission averages for hot running engines (ignoring the fact that cold starting, at the beginning of each commute in each direction, generates up to 40% of the total emissions on a trip). Unadjusted F.A.E. data is therefore too low.
2. F.A.E. does not take into account the fact that, as noted by several observations at different commute hours, roughly 35% of the private vehicles used in the commute in question are not fuel-efficient automobiles, but “fuel guzzling” trucks and sport utility vehicles. F.A.E. data is again too low.
3. F.A.E. statistics are based upon steady load engine tests that are not representative of a real commute on the route under consideration. The actual load profile of the road vehicles being compared has numerous major fluctuations. These include operations on both flat highways and long, steep grades north of the Golden Gate Bridge, plus a number of hills inside the city of San Francisco. In addition, dozens of vehicular decelerations, stops, and accelerations are required due to bridge toll, routine traffic congestion, traffic accidents, street maintenance, construction, and traffic signals controlling intersections. The glaring proof of this is the fact that an automobile, which can legally achieve speeds in the order of 55 miles per hour on this trip, actually needs at least 36 minutes to cover the 16-mile distance between downtown San Francisco and the ferry terminal area. This represents an overall average transit speed of 26.6 miles per hour or less. On a “good” commute day, the average is the result of roughly 9 minutes at reasonably good (but varying) speeds, and 22 to 27 minutes in “stop and go” traffic. On a “bad” day, trip time will increase 20 to 30 percent, or more.
4. It is well known that E.P.A. automotive fuel consumption ratings (miles per gallon) are listed under two categories: for highway and for city street driving. A midsize 1999 model automobile rated at 30 miles per gallon on the highway will only achieve 20 miles per gallon in city driving. This represents a fifty percent increase in fuel consumption and consequent exhaust emissions. The actual commute into San Francisco is heavily weighted towards the latter condition, with auto engine emissions increased proportionately. A fair estimate of average automobile, pickup truck, and S.U.V. gasoline mileage on the 16 mile trip under consideration is something in the order of 20 miles per gallon. Use of unadjusted F.A.E. is therefore a severely unrepresentative assumption.
The actual mix of vehicles, unavoidable variations in engine load profile due to operations ascending and descending grades, repetitious stopping and starting, and two cold starts per day demonstrate that unadjusted Fleet Average Emissions data is far too low for use in comparison to ferry engine emissions. It is totally inadequate for any serious study of the matter.
Bus Passenger Miles and Emissions
Just as Fleet Average Emissions cannot be used without adjustment to represent automotive emissions, dynamometer tests and revenue service passenger occupancy levels cannot be used for estimating bus emissions per passenger mile without substantial adjustments.
The average bus patronage on the route under consideration is 30 to 35 passengers per commute. While a credible statistic for revenue service, this number is inadequate for comparing total bus emissions per passenger mile because it fails to take into account the substantial amount of mileage a commute bus travels every day without passengers (deadheading) and with reduced numbers of passengers while in revenue service.
Buses do not provide the personalized door to door commute of automobiles. They are stored, fueled and serviced in centralized depots and each day dispatched to the starting points of their respective schedules without passengers. Unlike a personal automobile or transit ferry, a bus progressively accumulates passengers along the route and likewise gradually discharges passengers as it proceeds toward the terminus of its route each way (inbound and outbound). Upon completion of the daily inbound trip, some buses are stored in city parking lots awaiting the return trip (similar to commuter autos), but many others are rerouted to additional transit or fleet servicing assignments, frequently moving without passengers on these trips. As the time approaches for the outbound commute, empty buses are again repositioned to their respective trip starting points. Upon completion of the day’s operations all buses return, again empty, to the storage/fuel/service depot.
Evaluating passenger count and deadhead vs. revenue service for a major bus fleet is not a simple matter, because the actual numbers involved are route specific and can vary depending upon fleet servicing requirements, accidents and congestion, driver shortages, etc.
The situation can be explained with the following factual example. Every commute day Golden Gate Transit puts 216 buses into revenue service from Marin and Sonoma Counties to San Francisco. Approximately half of these are stored in San Francisco during the day for return trips in the evening. (The parking facility for these buses occupies one city block.) Half of the remaining buses are returned to service on alternate routes, with the balance returning for fleet maintenance or other purposes. For the transit bus routes under consideration, essential deadhead operations are estimated to constitute roughly 20 to 30% of the total miles operated per day. Every commute day and all the time these “passengerless” miles are being accumulated, the buses are burning fuel and generating exhaust emissions.
If the average fuel consumed (and emissions generated) by transit buses are increased by 45% over what is used in revenue service to account for the non revenue (deadhead) and reduced passenger operations, a more realistic appraisal of the total emissions produced per bus passenger mile will be obtained.
Bus Engines, Load Profile, and Fuel Consumption
All Golden Gate Transit buses are powered by one of three types of Detroit Diesel engines: the 6V92, Series 50, or Series 60. These engines, like those of the competing Golden Gate ferries, are conscientiously kept in good order by an effective preventive maintenance program.
The load profile of a transit bus engine is important. To begin, it involves at least one or two cold starts per day, each of which represents a period of substantially increased exhaust emissions.
Of greater significance, commute buses must make scheduled stops to receive and discharge passengers in addition to the stops an auto must endure due to the bridge toll, traffic signals, street repairs, accidents, congestion, etc. On a good day, a transit bus competing with the ferry achieves average trip speeds in the order of 24 miles per hour. This figure is a consequence of 36 to 40 scheduled and non-scheduled stops and accelerations per round trip. Bus engines therefore have an even more severely fluctuating load profile than that of the previously described automobile engines. Anyone who has been behind a diesel-powered bus as it accelerates is aware of the dark cloud of unburned hydrocarbon emissions generated during that condition. The load profile imposed on transit buses increases fuel consumption and emissions on the route under consideration by something in the order of at least 60% in excess of dynamometer test results.
The daily realities of essential transit bus deadhead trips, reduced passenger occupancy, and engine load profile have the cumulative effect of substantially increasing actual bus emissions per passenger mile far in excess of what would have been estimated by average revenue passenger count and uncorrected emissions data produced under a dynamometer test. It is clear that, like automotive F.A.E., uncorrected bus emission statistics are totally inadequate for making comparisons to ferry emissions.
Golden Gate Transit buses are used on both long and medium distance routes. Some involve long stretches of highway driving and others are more “stop and go” service. The estimated fleet average fuel consumption rate for this broad mix of routes is 4.5 miles per gallon. In consideration of the severe service conditions (steep grades and dozens of stops and starts involved) in the commute under consideration, a fuel consumption estimate of roughly 3 miles per gallon represents a reasonable, conservative number for the commute in question. This figure is supported by the well established 50% vehicular fuel consumption increase between highway and city driving, and is in the range of other documented bus fleet mileage statistics.
Ferry Engines, Passenger Miles, Load Profile, and Emissions
M/V DEL NORTE has been in service one year, and is the newest ferry in the Golden Gate fleet. The DEL NORTE Detroit Diesel 16V-149TI DDEC engines feature electronic injection control and should not be confused with a different make of engine improperly assumed by one study purporting to estimate engine emissions for M/V DEL NORTE.
The first item of significance to comparisons is the fact that the DEL NORTE route is twenty percent shorter than that of the competing land vehicles. Shorter trip distance is a common and major benefit of ferry services, and explains why relatively slow vessels are routinely able to get passengers to destinations in the same time or less, and burning less fuel, than land vehicles capable of much higher speeds.
The highly varying load profile of automobile and bus engines was discussed above, and explained as a significant factor preventing those engines from achieving the results established under Fleet Average Emissions and dynamometer testing. By contrast, the ferry engines of DEL NORTE operate at only two steady loads throughout 83% of the trip duration: at 10 knots for 10 minutes transiting the restricted waters of the Larkspur channel, and at 35 knots for 15 minutes in open water. The remaining five minutes of voyage time are spent departing and approaching terminals.
DEL NORTE’s engines are kept warmed up all day and therefore have only one cold start per day of operations.
Ferryboat engines are unique in having this kind of load profile advantage over competing land transportation modes. Ferries do not encounter grades and are free of “stop and go” street and highway congestion. The simple fact of the matter is that the ferry is the only transport mode capable of achieving the steady engine loads required for optimized fuel combustion and minimum engine emissions.
Ferry Passenger Occupancy
The DEL NORTE operates 98% full (320 passengers) during morning and evening commute runs, and has had to literally turn passengers away due to excess demand on numerous occasions. This is better than the 77% average peak occupancy of buses. Since the DEL NORTE entered service, the huge Larkspur ferry parking lot has been inadequate to contain the number of commuters’ vehicles. A second, much larger capacity ferry of similar design is now being planned to handle the projected increase in passengers.
Return ferry trips from commute runs naturally average much lower patronage. Many of these are almost deadhead operations comparable to those described above for transit buses. Off-peak patronage is likewise less than during the commute hours. (NOTE: As long as both bus and ferry patronage comparisons are based upon the same categories, namely either peak revenue service or total (peak plus deadhead) service, valid evaluations can be made. One prior study compared bus peak patronage to ferry average (peak plus deadhead) patronage, which led to seriously flawed conclusions.)
Emission Comparisons
The U.S. Department of Transportation is planning an in-depth engineering study to compare the engine emissions of autos, buses, and ferries. Until this study is completed, the auto vs. ferry emission comparison provided in Appendix C is considered a reasonable approximation for purposes of discussion. The results of Appendix C can also be reinforced by the following brief fuel consumption analysis, which is based upon the average commute hour patronage of M/V DEL NORTE: 320 passengers per trip. The previously defined statistics establish that to move the same number of commuters would require either 278 automobiles or roughly 9.1 buses.
The fuel consumption of DEL NORTE in September of 1999 was 37,072 gallons, consumed during 336 crossings, or 221 gallons per round trip.
The fuel consumption of the 278 automobiles for the 32 miles of driving at 22 miles per gallon is 404 gallons per round trip.
The fuel consumption of the 9.1 buses for the 32 miles of transit at 3 miles per gallon is 97 gallons per round trip.
Based upon the fact that engine exhaust emissions are largely proportional to fuel consumption, it would appear that buses generate roughly 44% of the ferryboat engine emissions per commuter, while automobiles generate 183% of the ferryboat emissions per commuter. These numbers are equivalent to those shown in Table 1 of the enclosed analysis.
A comparable set of figures could be developed using developed engine horsepower and trip duration time for the three transit modes.
Additional Ferry System Emissions Advantages
Besides the vessel operating features and conditions described above, the Golden Gate Bridge, Highway, and Transportation District and the San Francisco Municipal Railway provide a number of enhancements to reduce total commuter engine emissions and vehicular congestion on Bay Area streets and highways.
All ferry patrons are offered the option of free San Francisco Municipal Railway and Golden Gate Transit bus transfers for connecting round trips (from the ferry and back) to downtown San Francisco locations and outlying neighborhoods. These two public transit networks provide a highly functional and low emissions extension of the ferry system to all inner city destinations.
The two Golden Gate ferry terminals in Marin County are served by an extensive network of feeder buses. These extend the availability of ferry service into twenty-seven communities throughout the County.
The Golden Gate ferry commuter parking lot at Larkspur has special spaces reserved for electric commuter vehicles. These are equipped with battery recharging units to encourage the use of zero emission vehicles.
The Golden Gate ferry system has always promoted zero emissions by encouraging the use of bicycles by patrons. Bicycle racks are available on feeder buses and in the parking lots. Space is also available on the ferries for passengers who wish to transport bicycles across the Bay.
Ferry Boat Amenities
No discussion of ferry service would be complete without mention of passenger amenities. M/V DEL NORTE, like all the Golden Gate ferries, offers reliable schedules, food and beverage service, rest rooms, a smooth ride, and comfortable seating with an unsurpassed view of the scenic delights of San Francisco Bay. A ferry commuter always arrives on time and refreshed by the trip, which is in marked contrast to the typical experience of bus and auto commuters.
CONCLUSIONS
The fast ferry M/V DEL NORTE represents a thoroughly modern, safe, functional, economic, popular, and environmentally friendly alternative to land transportation in the San Francisco Bay Area. As the successful concepts embodied in ferry vessels and operations are implemented in other locations, both society and the environment will accrue substantial benefits.
Ferries have inherent advantages over other forms of transport. These advantages will only be strengthened by continuing progress in vessel and engine design technology and growing public awareness of ferries’ low environmental impact.
Economic and population growth pressures in metropolitan areas can be expected to increase public demand for ferry transit systems in the 21st century.
References
Bay Area Council/Bay Area Economic Forum;
Bay Area Water Transit Initiative Action Plan -Executive Summary- June 1999
Tidewater Regional Transit, Ferry James C. Echois Operations and Maintenance Manual, June 3, 1996
Fairplay Solutions, article “Norwegian Owner Adopts LNG Propulsion”, May 1999
Mr. Mark Glick, et al, GANA, Inc., Clean Urban Transportation Initiative, “An Experimental Pilot Project to Build and Operate Low Emissions Public Transportation: Featuring Three CNG-Powered Passenger Ferries, an Emissions Monitoring System, & Public Education Program”, May 1999
Dr. Kenneth L. Tuttle and Lt. Thomas C. Miller (USCG), Marine Diesel and Gas Turbine Engine Emissions, Society of Naval Architects and Marine Engineers, Nov. 11, 1999
Mr. Joseph Woerner, et al, Naval Surface Warfare Center, Carderock Division, “The Assessment of Fuel Cell Power Plants for Surface Combatants”, Sept. 30, 1994
Mr. William H. Kumm and Mr. Homer L. Lisle, Jr., Artic Energies, LTD, “Feasibility Study of Repowering the USCGC VINDICATOR (WMEC-3) with Modular Diesel Fueled Direct Fuel Cells”, May 1997
Mr. George H. Harlan, San Francisco Bay Ferryboats, Howell-North Books, Berkeley, CA 1967
MarineNews article “Projected Accident Rate for HSC Higher than Experienced” August 23, 1999
Enclosure
Dames & Moore, Ferry Boat Estimated Emissions in Comparison to Motor Vehicles, May 1999
NOTE: Enclosures not included. Contact SNAME Headquarters for E