Special Interest Group on Maritime Transport and Ports
a member of the WCTR Society
Genoa - June 8-10, 2000
On the Economic Impact of Ports: Local vs. National
Costs and Benefits
It is nowadays widely accepted that the positive
economic impact of ports tends to move away from a local environment
(the earlier 'port city') to a much wider and often international
one, including the consignors/consignees. It is thus the purpose
of this paper to take a fresh look at the current changes in a
port's production function, based on a territorial cost-benefit
analysis, i.e. taking into account that:
- The port industry is no longer a labour intensive one:
direct employment is decreasing, while some port-related activities
tend to move to inland locations;
- The port industry is becoming more capital deepening,
but given the functioning of international capital markets, the
relevant payback does not necessarily stay in full within the
- Due to horizontal and vertical integration strategies, international
groups often own firms which run terminals and port activities.
Quite often, port impacts on the local economy are no longer among
the location selection criteria of holdings, corporations and
administrative departments, who often lack managerial and leadership
- Port development requires increasingly more space (a local
factor) but land allocated to port activities seems to be paid
less than its opportunity cost;
- On the other hand, ports still remain important from a national
perspective: they generate taxes and duties and they often constitute
growth poles for national industries (e.g. manufacturing, transport,
logistics) and services;
- Finally, the costs suffered by local economies are
getting higher in terms of land consumption, coast waste, environmental
problems and traffic congestion.
The existence of a disequilibrium in the territorial distribution
of ports wealth is thus quite evident. For this purpose Port Impact
Studies are powerful tools for assessing port impact, although
there is an open debate on their main goals, on the different
methodological approaches and on their role in port planning.
Finally the paper attempts to formulate some suggestions for a
sustainable and efficient European port system, focusing on the
role of Port Authorities, investment policies, and on the meaningful
involvement of local communities in deciding the "quantum"
of port development.
1. Introduction: the rationale of the concept
of port impact
There is a quite evident difference between the economic
concepts of output (the technical result of a production
process) and that of input payback (the remuneration to
the factors used in the production). The case for ports can be
considered as a classical production process where land, capital,
firm and labor inputs (e.g. location, space, infrastructure, superstructures,
facilities, human resources, management and organizational skills)
are combined in order to obtain a certain level of output (throughput).
The point is that there is a general continuous interest
on ports' results, while the issue of ports input payback seems
to be perceived, if not less important, at least finally referable
to the traffic of the port as a direct consequence.
Ports are, in fact, internationally characterized
in terms of figures mainly by their annual throughput. Each year
major research institutes give the up-to-date figures of world
ports traffic (TEU, tons) mainly focusing on (i) their
shifts (upwards/downwards) in ranking, (ii) changes in
the commodity mix (e.g. the increase in containerized traffic,
the decrease in liquid bulk, etc.) and (iii) future forecasts.
Anyway, when an effort is made in order to measure a phenomenon,
implicitly there is also a not neutral slant in such approach.
This emphasis on ports' throughputs seems to cover just one side
of the medal.
What do really mean "high traffic" data?
We can say that a port that is increasing its throughput is first
of all a port that is "good" for the ship and the cargo
(are the shipowners, in fact, who choose the port according to
their port selection criteria and shippers' demand). By the way
all the efforts to evaluate port performance based on different
indexes (tariffs, transit time, reliability) are always referred
to the port users, and not to wealth production and distribution.
Therefore high traffic means "only" that a port is more
effective than other, or that it is more strategically located
close to important hinterlands and/or maritime routes. Anyway
it doesn't mean as a result that the port is creating "value"
to remunerate inputs.
Thus for successful ports we can think at the advantages and gains
collected by port users (namely multimodal transport operators,
carriers, agents, shipbrokers stevedores and traders) who extract
a big share of the economic rent (wealth) produced by ports, which
evermore rarely stops in the port region.
Therefore we can surely assert that ports throughput
is not a correct, unique and exhaustive way for evaluating port
real "performance". By doing so, the risk of a misunderstanding
between the user function (the utility provided by the
port for the ship and the cargo) and the production and
distribution function (the inputs required for achieve that
level of output, and their payback) could come about.
The paper aims at analyzing the impact of ports for local
economies, and its territorial distribution from a local environment
towards a global "borderless" economy, considering ports
economic impact as the "source" of inputs payback. The
need for a particular awareness of port impact and its evolution
over time is due to two main issues:
- The fact that nowadays there is no "automatic" relation
between the above functions. The remarkable growth in seaborne
traffic, in fact, doesn't mean that port economies are getting
wealthier. Although is quite difficult to evaluate the impact
of ports, the simple trend of traffic data, moreover in containerisation,
is, in fact, getting less and less significant.
- The fact that the link between ports and port-based
economies is changing towards a weakening both in the previous
ties and in the economic significance.
The paper is organized as follows. Next section (§2) will
briefly analyze the importance of assessing port impact on regional
economies. In §3 a survey on main causes for changing impact
of ports (from an economic, territorial, environmental and social
point of view) is presented. An overview of different frameworks
of analysis for evaluating the real positive and negative impact
of ports on local economies - with focus on the aims, methodologies,
results and correct use of such studies is given - is given in
§4. Finally the potential disequilibrium in ports
impact (namely between a local and a wider level) is analyzed,
stressing the importance of carrying the analysis beyond the local
level (§5), and some open points for a sustainable port development
are suggested (§6).
2. The economic vs. social trade off: the importance
of estimating port impact
The proliferation in the last thirty years of Port (economic)
Impact Studies (PIS), despite numerous controversies regarding
the strength of these kind of studies, is an indisputable objective
fact that, ultimately, proves their relevance.
National and local governments, Port Authorities
and port business communities, in fact, always stress the point
that the development of ports could be a key factor in the economic
development (and/or redevelopment) of local economies. Moreover
ports play an important role from a national perspective due to
the fact that they generate taxes and duties and they often constitute
growth poles for national industries (e.g. manufacturing, transport,
logistics) and services, improving their competitiveness.
This emphasis on ports benefits can be considered
as the driving force for a sound economic justification of expansionary
goals for ports activities (typically capital and land intensive
Although not formally stated in statutes, port management
of public ports, in fact, could be implicitly characterized by
a double aim:
- make the port attractive to users, providing a competitive
supply of services for carriers and shippers (micro-economic
or entrepreneurial aim);
- raising the welfare of its citizens, enhancing social welfare
in terms of income, employment, living environment, security and
other aspects (macro-economic or social aim).
Despite the even existing relations between the different goals,
a clear trade-off is stated: while on one hand strategies
of growth and development improve income and employment, on the
other may oppose other "social" goals (e.g. the need
for a clean environment, for a high quality of life, for new housing
And the outlined trade off is getting more and more difficult
to solve, i.e. taking into account some current dynamics:
- Due to the fact that many ports are close to the full capacity,
as the volume expands external diseconomies of scale, caused by
congestion and lack of space, worsen the living conditions (especially
for ports located in a urban context);
- The relation between port throughput and income and employment
for port economy is weakening;
- Fierce competition between ports is increasing and borders
between traditional hinterlands are fading.
As a consequence of this schematized conflict, the
expansion of the port industry should be considered, from a neutral
perspective, as ex post equilibrium between positive and
negative impacts of ports. Extremely simplifying, in fact, the
higher is the positive impact of ports on local economies, the
higher the level of port expansion that would solve the trade
off equilibrium, which maximizes the local utility.
Thus, only an accurate qualitative and quantitative
estimation of ports positive and negative impacts, focusing also
on the implicit risks as a result of spatially concentrated costs
and widely distributed benefits, can provide an important tool
in the policy makers decision process regarding ports development.
There seems to be a lack of convergence on the topic: different,
and sometimes opposite thoughts, concerning the role of ports
for modern economies, give rise to a hot debate.
Without approaching the matter of how structuring an efficient
PIS, Goss (1990) suggests at least four clear reasons for which
port expansion or improvement is likely to be an inefficient tool
of economic development strategy:
- Port benefits are likely to "leak" to users in inland
- Assisting and investing public money in a port will probably
mean assisting foreign exporters, some of whom will be able to
compete more effectively with home producers;
- Any public assistance to a port is likely to lead to higher
local taxes (local share of infrastructure financing), running
the risk to make the area less attractive to residents and possible
- Since the aggregate demand for labour within any given economy
is determined by macroeconomics factors, ports are competing among
themselves for a share of a reasonably fixed level of business
(e.g. the expansion of a port belonging to a range could also
be at the expense of lost trade in other regional or national
ports belonging to the same range).
Even if some of the outlined points have to be considered
in perspective of the current context of globalization and liberalization
of the markets leading to higher competitive environment and increasing
of spatial interrelations and volumes of cargo traffic (also as
a consequence of the improvement of the Hub and Spoke system),
Goss' argumentation still remains quite effective.
Moreover another important element has to be taken into account:
most of the literature deals with the problem of port economic
impact from a general perspective while it is quite evident that
several local/national features can affect the analysis.
Gripaios-Gripaios (1995) and Gripaios (1999), for
example, draw similar conclusions for UK ports; they provide empirical
evidence suggesting that often the existing and potential role
of ports in the regional development process is nowadays exaggerated.
On the other hand, looking for example at the Netherlands, NEI
(1996) and Bossche (1997), emphasize, even though raising problems
of sustainability of port development, the economic significance
of the port of Rotterdam for local and, mainly, national economy.
The topic is evidently complex and it is worth to deeper analyze
both the emerging changes in ports impact and the methodological
approach in conducting a port impact study.
3. Ports changing role (and its potential consequence
on impact): some economic and spatial evidence
It is nowadays widely accepted that the positive
economic impact of ports tends to move away from a local environment
(the earlier 'port city') to a much wider and often international
one, including the consignors/consignees.
From an overall perspective, globalization and deregulation
set the ground for currents economic developments in which economic
frontiers tend to fade and competition tends to intensify. Deregulation
also allows business companies to re-organize their production
systems internationally and to capitalize on advantages of different
countries and regions.
For a long time the presence of a port meant not
only traffic and transport activities, but also a wide range of
economic activities, ranging from industries using mainly raw
materials imported by sea and whose land transportation costs
would have been too high, to those producing goods to be exported
by sea and/or those whose optimal location was where the break
of bulk took place. Nowadays, many of these industries, no longer
technologically restricted to port areas, and suffering from the
relative scarcity and/or high prices of space and other inputs,
have moved to regions where these inputs are available at better
Besides, technological progress in transportation
(lower costs) has transformed port services market from a quasi-monopoly,
where the distance from other ports "protected" each
market area, to a more and more competitive market.
In this new scenario the "captive market"
situation has been overthrown, and port users are more and more
extracting the economic rent produced by the ports, leaving to
ports production inputs an even small payback. The growing horizontal
and vertical integrations involving terminal operators represent
both an oligopolistic response, aiming at achieving economies
of scale (horizontal integration) and the attempt of transport
operators to "take over" the port and its added value
Finally, innovations related to the port node have
been labour saving and capital intensive, as well
as - which can be considered almost unique - land intensive
(namely in containerised traffic). Besides the dramatic change
in benefits and costs related to the port, new and different costs
for the local community must be considered, like growing levels
of congestion and pollution or the loss of a large amount of public
resources (the coastal space).
Greater location indifference and diseconomies of
congestion have allowed production activities to move away from
ports. Since this coincides with an organizational upheaval of
transport cycle and a reduction in land transport costs, this
caused the growth of inter-modal inland terminals, which developed
scale and concentration economies, and polarized traffic and induced
activities. As a result, new spatial economic patterns arose,
built around the new foci and routes of the transport cycle. With
evident and deep consequences on ports and economic systems of
port regions (Musso, 1996).
Thus, relations between the port and its local economy
get weaker. Traffic flows increase, but port operations decrease,
become of lesser importance, and require less manpower. Ports
no longer give place to inter-industrial linkage, so that income
multiplier effects not only are less relevant, but they usually
spread over industries and economies even quite far from the port.
The real big risk is that more and more commodities just pass
through the port without stopping and/or without inducing economies
activities (the port as a simple transit point), employment and
added value (Vigarie', 1991).
Port services show a decreasing payback of labour
and an increasing return on capital investment. While the former
is located within the local economy, the latter, namely as a consequence
of above mentioned horizontal and vertical integration, seldom
comes either from the local economy or even from the country itself
(given the functioning of international capital markets, the relevant
payback does not necessarily stay in full within the port region).
This means that the economic impact of the port tends
to spread more and more over the entire area of port customers
(and often also internationally), while space consumption and
negative externalities increase and remain spatially concentrated
in the local system. This situation potentially brings about major
In summary, ports' records growth in throughput
has not led to a corresponding increase in the number of jobs
or in added value (sometimes also for all the transport and logistic
functions). Therefore growing investments in port infrastructures
and technologies are leading to an ever-widening gap between,
on one hand, the regional use of the resources of territory, natural
potentials and tax money and, on the other hand, the regional
effects on employment and added value.
In the outlined scenario, costs and benefits deriving
from the port should be carefully assessed, as well as their territorial
impact and economic actors taking advantage from it. Namely, it
is becoming ever more important using techniques for accurately
measuring positive effects of the port on the local economy. These
effects are largely related to the direct and indirect employment
impact within the area, since other inputs are increasingly of
external or international origin (firms and capital), or do not
attract a sufficient payback (land's rents).
This is relevant also from an institutional and financing point
of view, which will be reconsidered in the last section. In the
past ports were perceived as social capital and it was
the state that developed and financed ports infrastructures because
of their capacity of generating employment and other indirect
positive effects on the local and regional economy. But nowadays
that ports are no longer the milestone in the structure of employment
for the inhabitants of the port city, who are the real beneficiaries
of new, subsidized infrastructures needed to maintain ports competitive?
These sound doubts are leading to a different idea behind port
investments, perceived as an economic capital, till some
extreme positions that argue that ports should be developed and
exploited as purely economic units, where public sector could
not be always the prime mover (but, in a different perspective,
see Suykens, 1986).
4. Methodological approaches in Port Impact Studies
For their being "critically" important
there has been a series of economic articles discussing and analyzing
problems and potentials of PIS: Waters (1977), Chang (1978), Davis
(1983), Yochum-Agarwal (1987, 1988), Warf-Cox (1989), DeSalvo-Fuller
(1994, 1995), Gripaios-Gripaios (1995), Verbeke-Debisschop (1996),
Castro-Millan (1998), Gripaios (1999), Musso-Benacchio-Ferrari
(1999). Port Authorities usually invest on port impact research
too. As an example, the US Maritime Administration and the New
York and New Jersey Port Authority, in the late seventies, developed,
a famous regional port economic impact kit, based on a special
form of using input-output tables, which has been updated on several
occasions and which was flexible enough to adapt to the caractheristics
of small and medium-size US ports (U.S. Maritime Administration,
1979 and 1985).
4.1 Aims of PIS and the choice of economic explanatory
The basic aim of PIS is to show the whole of the
net economic benefits for local (surrounding) communities to be
associated with the existence and operation of a port. The defined
general aim of PIS could be composed of different sub-goals, each
of them can affect the choice of the proper methodology:
1) Facilitate the understanding of the (qualitative
and quantitative) relationships that exist between the port and
the regional economy;
2) Measure (also overtime) the regional economic impact caused
by the presence of the ports;
3) Operate as a simulation model, quantifying the economics effects
derived, for example, from investments in new infrastructure.
These positive effects can be evaluated in many different ways;
conventionally they are measured by the contribution of the activities
of the port sector (in a broad sense) to the level reached
by some economic variables such as: employment, added value, incomes,
taxes and duties.
Quite often analyses are concentrated on employment terms
considered as the most satisfactory proxi of the main economic
positive effects for the local system. On the other side one can
argue that the added value created by the port is the best
variable for assessing the role of ports as catalysts for the
creation of economic wealth.
In principle it could be correct, because the concept of added
value is the most comprehensive measure of the actual wealth produced
by ports. It is quite evident that ports who achieve to establish
industrial and logistic linkages are able to produce (and potentially
extract at a local level) a wider economic rent from direct and
indirect port activities.
However some remarks can be outlined on the use of the concept
of added value.
First of all employment is a clear (even if rough) indicator of
the payback of a typical local input (labor), while added value,
which could be a more powerful estimator, refers to the wealth
produced and induced by the port without providing details on
its distribution. For instance, what is the share of added value
that goes in taxation (local and national)? Moreover if an input
such as space were free, the added value of ports would be higher,
but the local impact would be lower. Therefore added value figures
are useful in providing a better knowledge of ports impact jointly
and not alternatively to employment figures (the ratio "added
value per employee" is a good measure of the economic significance
of the additional port functions).
Secondly it is an estimator whose measurement is usually more
subjectively biased than the employment figures. Substantial differences
can be observed as regards the definition of the value-added concept.
More specifically, inter-port comparisons reveal differences in
defining, calculating and determining a weighing rule for converting
nominal tons into intrinsic cargo handling or value tons (Charlier,
1996). Haezendonck et al. (2000) mention at least four
different weighing rules within a single range, such as the Hamburg
- Le Havre range, even if, in general terms, the value added concept
always aims to assess the contribution of port activities to a
nation's Gross Domestic Product.
Thirdly, as well as for port-related employment, it is not clear
if (and in what way) the volume and the traffic structure of ports
matter in value added creation (while they are chosen as the independent
explanatory variable). Moreover if value added is computed from
Input-Output regional (or national) matrixes, the same advantages
and drawbacks seeable for employment can be outlined.
Finally, there is no reason, due to the globalization of the
economic processes and firms' ownership, to support the evidence
that the higher added value produced by logistic ports as Rotterdam
and Antwerp surely stop in the port region. In fact the current
trend of a widening and cross-bordering port economic impact is
confirmed also by added valued focused researches.
4.2 Definition of economic impact
Taking the employment as a proxi of the concept
of ports economic impact we can distinguish:
- primary (direct) impact:
"all activities necessary for the operation and use of the
- secondary impact:
"all the economic activities of the area of influence of
the port (local community and hinterland) that economically depend
on primary activities" (Castro-Millan, 1998).
It is not easy to avoid the risk of subjectivity
in the definition of the economic activities involved.
Davis (1983) distinguished the direct effects
as the employment from the set of activities necessary for the
operation of the port and other activities related to the outgoing
and incoming shipment of the goods and passengers. The precise
relationship of this set of activities may vary from port to port,
which shows, on one hand, their different economic orientation
and, on the other, the absence of consensus as to what economic
activities are truly necessary.
He splits secondary impact into two kinds of effects:
indirect and induced. Indirect effects refer to all economic
activities developed in the port region and dependent on the primary
activities through a technical relationship, fundamentally of
the buying and selling of goods and/or services. Induced effects
refer to all activities that also take place in the wide port-region
and that depend on the direct and indirect effects through "consumption"
The tri-partition of port economic effects can be
considered a stable distinction in different studies.
Yochum-Agarwall (1987, 1988) proposed an interesting
conceptual framework in which they provide general guidelines
for conducting a port's economic impact analysis. The organization
of an efficient search for port-related industries is based on
three different linkages between the port and the region's
- Employment in firms providing services necessary
to the movement of waterborne commerce (port required industry).
- transportation services (e.g. freight forwarding,
transport of cargo by rail and road);
- port services (e.g. terminal operations, stevedoring,
vessel supply, pilotage, towage, ship repair, diving services,
insurance, legal services)
- Employment in firms attracted to the region because
of the presence of the port (port attracted industry).
The availability and potential access to port facilities may well
serve as a "magnet" to attract industries to sites located
near a port. The economic advantage of close proximity to a port
is such that port attracted firms would considering moving from
a region if the port facilities were closed down. They typically
fall into two categories:
- firms that export commodities;
- firms that import products or raw materials for
assembly and distribution (e.g. steelworks, chemicals, refineries)
- Employment in firms that have expanded their
markets (demand for their products) by exporting through the
port (port induced industry). The port is a source of reduced
transportation costs, which results in industry expansion. Such
industries are typically located at a substantial distances from
port facilities (and on the basis of a mere geographical criterion
they would not be correctly identified). They are port dependent
in that cost-effective access to the port affects demand for the
firm's products. Such industries however could be located in the
region regardless of the availability of port facilities (therefore
is much more difficult to establish their degree of dependence
on the port).
Quite similar is the "Dutch" functional
approach to the segmentation of the economic impact of ports (Bossche
van den, 1997), in which are distinguished:
- Direct economic effects
Those effects are related to the "core"
of the port. It concerns the actual employment (and gross added
value) to be found at the - geographical - centre of the port
(related to the basic activities carried out in the port).
- Backward linkages
To perform their core activities, the economic actors
that are comprised in the direct effect will use goods and services
from subcontractors who need other subcontractors and so on. The
total amount of employment connected with those subcontractors
ads up the so-called backward linkages. The ratio between backward
linkages and direct effects is called the backward multiplier.
- Forward linkages
Without the presence of the port, those activities
either would not take place, or would take place against higher
operating costs, or would be located elsewhere (maybe outside
the national economy). As for the previous port induced industry,
it is much more difficult to measure forward linkages in an objective
and transparent way (e.g. risk of overestimating for possible
The picture is greatly complicated by what we can
call the "historical" employment impact: that is, the
employment in industries that are still located in the port area
because they used to be "port oriented" in the past.
Moreover all these definitions implicitly identify
a fourth set of firms that are not affected at all by the presence
of the port. But it is not certain whether the fourth group even
exists, as it is arguable whether any sector exists that is not
at all affected by the distribution of wealth originating from
This is why, finally, also preliminary approaches
concerning definitions can affect results from different PIS that
should never been compared a-critically.
4.3 Choice of the methodology for employment assessment
- Rough guess methods, ad hoc survey methods
It is not rare to find port impact studies not based
on rigorous methodology. When the "political" aim (i.e.
emphasis on the port benefits) is the real goal for generating
communication among main parties involved in the decision processes
leading to the allocation of public resources to seaports projects,
the issue of methodological approach for a careful assessment
fades into the background. Port Authorities quite often justify
tailor-made solutions due to the peculiarity of the case study,
but they do not provide transparency on calculations. For a critical
survey on such "geographical" and ad hoc survey
methods for estimating port employment and value added see, for
example, Isemar (1997) and Haezendonck et al. (2000).
- Models of port demand
Following a series of empirical studies based on
the port of Tampa (USA), DeSalvo and Fuller (1994, 1995) have
advanced a methodological proposal which attempts to offer a simple
conceptual framework to evaluate a share impact of ports. The
impact depends (i) on the cargo volumes transshipped by
the port and (ii) - taking into account the changes in
local output due to price changes - on the price elasticity of
the demand for imports and exports channeled through that port.
They showed that a reduction in both exports and
imports (due to an exogenous "shock": a stop or a decreasing
in port activities), will cause, besides a loss in direct employment,
an increase in transportation costs. This will lead to a final
result of higher sale prices of the products and a progressive
reduction in the global quantity imported/exported). Moreover
also internal production costs, and consequently, the sale price
of the domestic products that use imported goods in their production
process will boost. This, in turn, will bring down the demand
of such products, which, sooner or later, and depending on the
market structure, will mean a reduction in employment and output
in the analyzed area.
- The economic base approach
The central aspect of the model, which implies that
exports have an autonomous behavior, rests on the believe that
regional income critically depends on the export sector, where
the economic base multiplier is expressive of the changes income
would experience in light of autonomous changes in exports.
The adoption of this model, in particular for port-impact
analysis (Isemberg, 1957; Kraft, 1966), has been criticized for
three main weaknesses:
- It considers as a non-basic (or endogenous) sector
all activities related to the flows of imports;
- The model only provide an aggregate multiplier
(a substantial increase in exports of a determined good has exactly
the same multiplying effect as an equal increase in exports of
a different good);
- The model mainly computes the induced effects
without offering satisfactory assessment of the indirect effects.
- The Keynesian Income-Expenditure approach
This model, derived from the core of most macroeconomic
demand models, has been suggested to calculate the secondary impacts
derived from port activity. In the income-expenditure final multiplier
the critical element is the marginal propensity to consume goods
From the point of view of port economic impact studies,
this approach, which has some advantages over the base-export
models (it considers that imports substitution can constitute
an income-generating factor), has also the disadvantage of only
providing one multiplier for the computation of the induced effect,
and not offering any information about the technical and/or economic
interrelations that exist among different sectors.
- The Input-Output Approach
One of the most fruitful approaches to assess port
economic impact is that based on an input-output analysis (Warf-Cox,
1989 and Castro-Millan, 1998). The system of producers and consumers
is divided into different branches, which are defined in terms
of the resources they require as inputs and what they produce
as outputs. The quantities of input and output for a given time
period, usually expressed in monetary terms, are entered into
an input-output matrix within which one can analyze what happens
within and across various sectors of an economy where growth and
decline takes place and what effects various subsidies may have.
In this way, the impact of the previously defined port-related
sectors can be computed with a breakdown level depending on the
There are several reasons supporting the utility
of the model. Firstly because this kind of analysis allows obtaining
a multiplier for each one of the activity branches considered.
Moreover, if also private consumption and households wages and
salaries are considered, it permits to compute the whole sectional
multipliers (including then direct, indirect and induced effects).
On the other hand this method is very expensive (in terms of costs
and time) and sometimes national I-O matrixes are used for a long
period for regional purpose (with an evident lack in local details).
- Adjusted Location Quotients
Musso-Benacchio-Ferrari (1999) proposed (and applied
to Italian ports) a technique for estimating the port's employment
local impact assumed as the employment that can be ascribed to
the port within the above mentioned direct, indirect
and induced impact.
Employment impact is evaluated in terms of shares
of employees to be ascribed to the port impact according to the
estimated probability that industries are totally or partially
port oriented (compensation approach). The technique basically
consists of rules for estimating the importance of port in the
employment of each industry. It is a mix of four different analytical
- the "control regions" technique, for
the territorial definition of port economies and non-port economies
(PE and NPE)
- the location quotients analysis, for the comparison
between port economies and non-port economies
- the shift share analysis, for the attribution
of the share of employees for each selected industry belonging
to a port economy
- calculus of probability, to remove the random
and/or biased component from the data.
The many advantages of the proposed approach are
in the sense that:
- it avoids any discretional bias: there is no
arbitrary evaluation, neither on definition of "port related"
industries, nor in the share of employment attributable to the
- it is relatively easy, from the point of view
of time and cost, in that it does not require direct data collection
but just census data: in most advanced countries there exists
data available on employment, with suitable level of territorial
and industrial breakdown.
By the way there are still some points open to improvement:
- it gives rise to a strong discretion in the choice
of homogeneous control regions (which ideally should be homogeneous
to the PE except for the existence of the port);
- the problem of underestimation as a result of
compensations has no satisfactory solution, but can only be coped
- the proposed technique does not join with input-output
methods, neither with the wider Keynesian macro-economic inducement
4.4 Some empirical results
In principle, comparing results obtained from different studies,
different methodologies and different periods is nor easy neither
A part from methodological issues, it is important to state that
PIS are first of all decision supporting tools for regional planning,
giving an estimation of ports inputs payback, and not a sort of
model for benchmarking ports impacts in different contexts. In
fact even if it were possible to compare ports positive effects
computed for the same time and unbiased by methodological approaches
and discretionary estimations, what would be the "added value"
of such a comparison? Port direct and indirect activities have
in fact a very close causal link with the historical, geographical
and institutional background of the local economy, which are elements
not at all (or partially) under the control of the port community.
Moreover what could be considered as a higher economic impact
in terms of employment or added value might be lower, compared
with other ports, in terms of dues, duties and tax flows.
A comparative table of the results from different PIS is therefore
here included just to provide some general elements of discussion.
||Elaboration on census data (geographical criteria)
||Elaboration on census data (geographical criteria)
|Nantes/St. Nazaire (FR)||1995
||I-O + weighed estimation|
||Geographical criteria + direct survey: only direct employment
||Geographical criteria + direct survey: 56,770 (direct)
||Geographical criteria + direct survey
||Geographical criteria + direct survey
||Direct survey + I-O analysis: 63.000 (direct) + 35.000 (backward) + 62.500 (forward on the national level)
||Adjusted Location Quotients|
||Adjusted Location Quotients|
||Empirical survey + I-O analysis|
||Employment in a-priori defined port related activities: sea and coastal water transportation, cargo handling, storage, warehousing, other transportation activities and other transportation agencies.
||Survey + Estimation: direct + Indirect
|New York/New Jersey (USA)||1977
||I-O + survey techniques. Induced effects computed for USA
|New York/New Jersey (USA)||1985
||I-O + survey techniques. Induced effects computed for USA
|Hampton Roads (Virginia, USA)||1984
||Direct surveys: 12738 (p-required) + 3399 (p-attracted) + 29595 (p-induced)
Sources: Isemar, NEI, Warf-Cox, Yochum-Agarwal, Musso et al.,
Castro-Millan, Gripaios-Gripaios, Gripaios.
The wide range of values and approaches suggests some comments.
From a methodological point of view most of the studies, besides
using sophisticated techniques, can't avoid a share of subjectivity
(interviews, surveys, estimations). Moreover, the input-output
matrixes used are "adapted" (regionalized) from
national economy I-O matrixes, when a regional one is not available.
Beside the fact that it doesn't seem to be a transparent method
due to the fact that details of the "regionalising"
procedures are not given, moreover this doesn't allow to take
into account several local economic features.
Concerning data, it seems to be no apparent relation between the
estimated impact and the total volume of ports throughput. A more
accurate analysis (as performed by Warf-Cox, 1989) should distinguish
between changes in cargo volumes, and changes in the commodity
mix. The impact attributable in to changes in the commodity mix
arise from the fact that different commodities require different
handling methods, and thus different amount of labour, material
and service inputs for their loading and unloading. For example
a rise in the share of trade accounted for containerized traffic
will decrease aggregate direct labour inputs such as stevedoring
services, potentially increase indirect effects due to logistic
activities performed on high value goods, increase capital investments
and expenditures on items such as fuel oil, in turn indirectly
altering patterns in the local economy. Within the traffic mix,
the role of transshipment is generally not taken into consideration,
while the effects of passengers (ferries and cruises) usually
seem to be underestimated. Moreover, while all of the studies
report global figures of port-related employment, few of these
try to analyze the breakdown in different categories (e.g. Warf-Cox,
1989). Nevertheless it is quite evident that the structure of
the induced employment (workers, professionals, engineers etc.)
is an important indicator of the quality of the impact, of its
added value and of the leadership functions of the port region.
Moreover, the fact that containerization and standardization
of cargo and related procedures may change the role for ports
from industrial/service linkage to a simple transit point, sometimes
can also lead to moves of main port related premises of holdings,
corporations and administrative departments towards inland locations,
while executive branches still remain close to the port. This
has to be seen as a high risk for the port local economy to loose
important managerial and leadership functions.
Finally, the computed results are, in general, not so relevant.
Moreover quite often the growth in tons does not lead to a comparable
growth in terms of employment (for instance the throughput of
Rotterdam grew on average 1.6% per year during the period 1987-1997,
while direct and indirect impacts decreased on average 2.8% per
year). In that respect the causal relationship of port and city
economy has been reversed. Ports are no longer the economic engines
of seaport towns, while the differentiated production and service
networks of the region constitute a prerequisite for the economic
benefit of the ports in term of a value added and employment oriented
service center (i.e. the case of Rotterdam and Antwerp).
All the above considerations implicitly stress the point that
PIS are more effective if repeated over time in order to constantly
monitoring changes in the economic relationship between the port
and the city.
4.5 Main criticisms to PIS and their role in economic and
There are several critics moved versus port impact studies.
The "original" criticism made by Davis (1983) pointed
out the lack of a thorough investigation of the degree of dependency
on the ports of the various activities included in the impact
component. PIS investigators, in fact, not only have to face with
the obstacle of searching for firms whose business is related
to the port (roughly the first task), but, once identified, they
have to establish the degree of a firm's (industry's) dependence
on the port (second sub-goal). Unfortunately, due to its nature,
the assessment of this degree of dependence runs the risk of a
very subjective estimation. When data are lacking to correct assess
ports impact, there may be a strong bias, of some of the parties
involved in the decision making process, to overestimate mainly
The second criticism of PIS has been on their practical applications
in terms of either estimating period to period changes in economic
impact or measuring the incremental benefits of additional port
investments. Waters (1977) attributed to these lacks the drawback
that PIS usually do not provide useful guidance for port planning.
Chang (1978) stated that "PIS are static in that these studies
measure the economic impact of port operation usually for one
year only during which collected data are relevant".
The need of replications over a period of time, in order to use
impact studies in a more correct and powerful way, is quite evident.
The fact that, despite all the outlined remarks, PIS usually remain
una tantum studies, is due on one hand to the high cost
of data collection and calculation of this kind of analysis, and,
on the other hand, on the short term political aim which is usually
associated to PIS (promoting port expansion).
The most significant and relevant criticism made by Randall (1988)
on the use of economic impact studies in the forms indicated above,
is that the selection of port specific industrial categories does
not reflect the true functional profile of the port. He emphasizes
the natural "proactive" role of seaports and, on the
basis of the current trends in cargo handling (namely capital
intensification and space consumption), supports a sound justification
for Port Authorities to engage in non-marine economic development
(from real estate agency and development to custody of bridges
and tunnels, from industrial tourism to co-ordination of community
festivals). A part from the wealth effects, these non-marine functions
often play an important role both in promoting the port itself
and in strengthening the link between the port and the port community.
A further remark is in the sense that PIS usually fail to provide
reliable guidelines in determining whether or not port facilities
should be expanded (while quite often they are used exactly for
this goal). The simulation role of PIS has to be carefully considered.
First of all it is important that they provide to assess the likely
effects of projects in terms of sustainable employment
and/or added value in order to avoid overestimated unrealistic
expectations (e.g. construction and maintenance effects have to
be reduced by the component which is probably not very different
from other projects, while economic trends which are not sustainable
over time have to be removed). Secondly they should be used only
to estimate a port's short run economic impact, since technology
is held constant, while the structure of the port (organization,
management, equipment) may change. Furthermore port economic activities
are affected by international events and by institutional changes
More reasonably we can summarize that PIS serve as an important
tool to the community in understanding the structure of a port
as well its immediate economic effects. They can provide insights
for a meaningful address in port planning: from a pure supply-led
transportation strategy (which sometimes leads to port
overcapacity in order to compete in the market), to a more
balanced incremental stepwise combination of supply-led and demand-led
There is a further point that seems to be quite important and
often underestimated. PIS are seldom recognized as an aid to the
decision making process on the overall economic regional planning.
The usual perspective of utilization, in fact, is quite "narrow":
politicians and decision-makers usually look at them as the main
tool for port (expansion) planning.
If the first general aim of PIS is to provide a detailed analysis
of the existing relationships between the port and the regional
economy, then we have to agree that their utility is wider than
that of a "black box" for simulating port impact under
Their "added value" is to give a better knowledge of
the economic framework of a port region and therefore they have
to be considered as an important layer in the economic and spatial
planning of the whole region. They support economic evidence (the
benefits of the port) that have to be compared with costs, and
then translated in options for an integrated global economic
planning, and in priorities for better decisions on the
economic, social and territorial development of the region (as
well as other sector studies).
Only if PIS are considered as an important "cognition"
estate for the local government, and their key role in port planning
is correctly integrated in the overall economic planning, it could
be possible to limit some of the frictions between the different
players involved (port users, community groups, local business
community, different government layers) enhancing cooperation
and synergies (Hoyle, 1999).
5. The "local" cost-benefit analysis and the "wider"
(national, supranational) context
The port economic impact (direct and indirect) has finally to
be compared to the costs suffered by local economies that are
getting higher in terms of land consumption, environmental problems
and traffic congestion.
Schematically we can outline the main (monetary and non-monetary)
costs of the port presence for the local economy as in the following:
- The local share of investments in maritime and port infrastructures,
- Opportunity costs of port industry inputs: capital, labor,
space (coast and landscape);
- Negative "sunk" externalities: environmental aspects
(air, water, acoustic pollution), landscape decay, irrecoverable
investments in facilities, traffic congestion, costs for "conciliating"
the presence of the port in a urban context, the risk of hazardous
material handling (chemicals, petrochemicals);
- Eventually loss of managerial and leadership functions for
local port economies that are quite no longer among the location
selection criteria of holdings, corporations and administrative
departments of the firms located within the port region.
Verbeke-Debisschop (1996) argue that, even when PIS correctly
perform a cost-benefit analysis, they usually don't take into
account "external effects and do not allow to introduce shadow
prices for the valuation of specific inputs and outputs".
Given that the market prices are used for the measurement of all
the costs and positive effects (when they are monetary valuable),
any distortion of the market from a perspective of economic efficiency
will lead to a biased picture of the real effects. Due to the
fact that in port production function imperfections usually affect
the inputs market (e.g. for the mechanism of land allocation and
pricing in ports) the risk of overestimating net port impact is
The quite evident disequilibrium between a reduced positive
economic impact of ports, which tends to move away from a local
environment to a much wider and often international one, and the
increasing costs and negative externalities, which remain spatially
concentrated in the local system, seems to have no straight solution.
A problem of territorial distribution effects in fact occurs,
taking into account that:
- labor usually comes from the local port economy and its payback
stops in port region;
- capital more rarely originates from local systems while it
is quite often provided by national and international systems
(and consequently its payback doesn't stop in port regions);
- firms may be local actors, but horizontal concentration
(between big stevedoring and logistic companies) and vertical
integration (between shipping companies and terminal operators)
tend to internationalise firms ownership;
- port land use is usually regulated by leasing and concessions
contracts but quite often land prices are a strategic tool for
attracting companies and they don't reflect real value of the
- the use of the fixed social capital of the local system (namely
transport infrastructures) is free (free-toll roads and highways)
or it pays fees sometimes lower than costs (e.g subsidisation)
to economic agents who often operate on a wider territorial scale
(rail, motorway operators);
- taxes and duties are just partly earned and managed by local
- port users who benefit from port benefits are more and more
spread all over the world, while negative impacts affect mainly
The outlined impasse seems to have no straight solution:
the risk is that of a "refuse tip" effect, such as ports
as facilities not desirable for local communities, more and more
necessary for other countries economies while more and more economically
less significant for their regions (Musso, 1996).
It seems meaningful, therefore, (re)considering the dis-equilibrium
between cost and benefits for the local economy within a wider
comparison between global cost and benefits, including those for
the hinterland. Ports, in fact, still remain very important even
from a mere national perspective. They generate tax flows and
duties, provide direct positive effects on Gross National Product,
Balance of Payments and Balance of Trade. Wider effects are in
the sense that ports constitute growth poles for national industries
(e.g. manufacturing, transport, logistics) and services, act as
macro-economic tools for territorial policies aiming at developing
depressed areas, and provide access to international markets and
On the other hand national costs for ports development seem to
be sum of the local negative impacts (although not directly equally
suffered by all the population), with in addiction:
- the national share of investments in maritime and port infrastructures,
- organizational and coordinating costs between central government
and local port authorities/harbour master offices;
- human resource costs (e.g. early retirements funds for ex-dockers
Even if these costs can be considered still compensated (even
if with a decreasing margin) by overall benefits, a clearly imbalance
on costs and benefits distribution still arises.
Finally according to the perspective of a wider overall economic
system port industry plays more and more an irreplaceable role
as central links in the logistic chains of the global economy.
Port users benefit from the port activities mainly in order to
reduce their own production costs and increase demand of their
product and services.
Providing a comparative overview of the results of five investment
projects in Belgian ports, Blauwens (1993) shows, in the form
of the net return per invested Belgian Franc (benefit ratio),
that the benefit count is usually lower from a Belgian point of
view than from an international one. In recent studies NEI (1996,
1997) has investigated the size of the forward linkages connected
to the Rotterdam port activities both on a national and European
scale. On the national level the direct effect brings along forwarded
linkages for the 70% of the direct value added, and for the 100%
of the direct employment. The cross-border relationships between
the port and its users in its hinterland are even more evident.
In 1997, on a basis of 24 billion Nlg of national added value
generated by the port, an additional 24 billion Nlg of gross value
added can be found in other countries (mainly in Germany and Norway).
Another important element has to be added to this unbalanced scenario,
underlining the lack of control by port communities in the strategic
planning of port development. Although port positive effects for
regional economies are fading, ports are more and more under pressure
due to the current high shipping lines volatility in calling at
ports (Meersman et al., 1999) and the already highlighted location
indifference of port related firms. This force ports (and port
economies) to face potential crisis through a unconditioned supply-driven
port planning leading to a structural overcapacity which worsen
local conditions. Such a vicious circle may determines potential
severe conflicts between local community and decision makers concerning
port matters, sharpened also by the perceived lack of representation
of local interests by port governance.
6. Facing the disequilibrium: some open points towards
a sustainable port development
All the above considerations could be synthesized in the following
Within such a scenario could be still realistic (and to what
extent) considering ports as catalysts for regional economy growth
- the increasing competitive environment between ports decreases
single port's economic rent;
- growing investments in new port infrastructures and technologies
are leading to an ever widening gap between, on one hand, the
regional use of the resources of territory, natural potential
and tax money and, on the other side, the regional effects on
employment an added value;
- while benefits are generally increasing, their distribution
effects are widening (towards a "borderless" economic
system) and they are becoming less concentrated in the local port
- the local communities are bearing the weight port industry
development, and the risk of an irrecoverable overcapacity;
- social conflicts related to port development are getting more
and more important (Port Authorities, community groups, business
community, national and local government).
The issue has to be carefully addressed. It is, in fact, correct
to look at the economic role for ports from a global perspective
taking into account at the same time regional and wider contexts.
While the former perspective of ports as powerful economic tools
for regional growth seems to be outdated, the mere consideration
of ports as critical links in the global transport network bypasses
the main problem of a correct input payback for the local system.
The synthesis can be achieved in recognizing that the issue of
port development it is not an unconstrained maximisation model,
but, first of all a matter of (spatial and overtime) sustainability
of costs and benefits.
From a local point of view the idea of port sustainability
implies the improvement of the trade off between costs and benefits
(first of all through a more correct payback of ports input),
and the possibility that the all the actors belonging to the port
community (local community in primis) can play an active
role in deciding the "quantum" of the port expansion
and the amount of the resources to be allocated.
Several open points can be outlined concerning different factors,
about which decision makers (at local, national and European level)
should argue in order to co-operate in drawing meaningful policies,
and consequently actions, for a fairer distribution of port effects.
Impact assessment - The first and concrete step
in such a broad topic should be the effort of adopting common
conceptual frameworks and "objective" quantitative methodologies
in order to assess the role of ports for economic systems in terms
of (i) local impact (direct-indirect employment
and territorial impact), (ii) fiscal flows and returns
on investments, (iii) international effects of the ports
within a global economy.
Land use and pricing - Concerning inputs of port's
production function, a suitable market structure in port land
use (at the same time efficient for the "supplier",
i.e. the local community, and effective for the "purchaser",
i.e. direct and indirect users of port services), can be considered
one of the main priorities (Musso-Benacchio, 1999). Consistent
rental policies have to try to link as much as possible leasing
rents directly to the costs of local communities (including opportunity
costs of space) not otherwise countervailed by benefits.
Port Infrastructures - New schemes for infrastructure
pricing and financing have moreover to be implemented, in order
also to correctly apply the user pays principle stated
by the major recent policy document of European Commission (European
Commission, 1997). Following this perspective an efficient decentralization
of port tax systems could be considered as a first step for allowing
ports (mainly in the Mediterranean area) to have more control
on investment decisions.
Port networking strategies - It is not a futuristic
scenario that which foresees breaking through administrative borders
of single ports entering into partnership with surrounding nodes
and regions (Van den Berg - Van Klink, 1997). This could lead
to a more rational planning, selections and locations of port
activities. Control of knowledge-intensive activities and co-ordination
of partnerships with other nodes could be considered as ports
core new business, allowing port regions to held leadership and
control of all transportation and logistical flows and related
added value activities.
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players (directly and indirectly) involved in port planning (from
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