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Models Of The Transportation Sector
In 1964 the railway was closed down for economic
reasons, and that left road transport as the only mode of internal
transport in the country. Economic development of the last decades
has resulted in the growth of that sector. The number of registered
motor vehicles in 1980 was 69,830 and at the end of 1993, fourteen
years later, that number had risen to 168,160. A 2.4 fold increase.
Motorisation rates in Mauritius are higher than on
the African continent but much below that of Western Europe or
the United States as shown in the following table
Motorisation Rates (per 1000 population, two wheelers excluded)
African Continent 20
Mauritius 160
Western Europe 416
United States 746
That leaves one household in five with a car. The recent annual rate of growth has been 13%, and excluding two wheelers, the annual rate of growth is still about 8%. A very high figure indeed. If such an annual rate of growth (8%) is maintained over the years, the doubling rate is close to 10 years, meaning that in 10 years time there will be twice the amount of motor vehicles as there is at present.
The economic, social and environmental impacts of
the doubling of the number of vehicles in such a short time will
be considerable to say the least.
The freight carried by road transport can be divided up into two types: sugar and general goods.
Sugar cane is first transported from the fields to the factories for processing and then the final product is transported to the Port Louis Bulk Terminal for shipping.
On average, 5 million tonnes of sugar canes is carried form the fields to the factories and then close to 600,000 tonnes of processed sugar is transported from the factories to Port Louis. Assuming 120 days for a normal harvest season, then around 40,000 tonnes of sugar canes and around 5,000 tonnes of processed sugar is transported daily.
The general goods category consists of merchandise, imported foodstuff, textiles, cement, goods for export and so on. It has been estimated that the total daily tonnage available for haulage is about 13,000 tonnes ( Ref 1 ).
In 1991, the lorry fleet totalled 7225 vehicles out of which 60% consists of light trucks with a tare weight of 3 tonnes or less.
Freight rates are not controlled and so there is
strong competition amongst the different operators. Generally,
the supply of freight services is enough to meet the demand.
Private transport consists of private cars, dual
purpose vehicles, motorcycles and autocycles. The rapid economical
development of the last decades has brought about a massive increase
in the number of private vehicles from 60535 in 1983 to 142930
in 1993, an increase of 136%. The number of private vehicles per
1000 population has gone from 62 to 136 in the same period.
Public transport is made up of buses and taxis. Buses are the main form of public transport in Mauritius. There are about 4000 taxis and 1700 buses operating throughout the island. There are three types of bus operators:
(1) a parastatal body: the National Transport Corporation with a fleet of 430 buses.
(2) four private companies with a combined fleet of 445 buses
(3) 560 individual operators with 825 buses.
During the period from 1985 to 1992, the average
number of passengers carried daily during weekdays went from 550000
to 740000, an increase of 33%. A third of all daily passengers
travel up and down the Port Louis to Curepipe corridor which is
served by around 350 buses. Traffic congestion over the same period
has increased journey time on that same corridor by about 40%.
The road network reaches about 1900 kilometres with
a density of 0.97 kilometres per square kilometre with 90% of
the roads paved. Though, over the last decade the density has
only increased marginally from 0.95 to 0.97, the existing network
has been vastly improved. But the density of vehicles per kilometre
has increased from 39 in 1980 to 92 in 1993, resulting in traffic
congestion at peak times.
Around 40% of energy demand is for transportation
purposes. Diesel accounts for 55% of transportation fuel used,
45% being petrol. This ratio is typical of developing countries
where price and fuel taxation are geared to promote the use of
diesel.
It has been estimated by Baguant (1996) that in 1992
the annual bus diesel consumption amounted to 20 million litres
and 92 million litres for goods transport. Whereas the annual
total gasoline (petrol) consumption amounted to 94 million litres
for the same year ( 2 wheelers and 4 wheelers included).
Baguant (1996) modelled the transport sector using
historical data from the Central Statistical Office over the 1970
to 1992 period. It is not our purpose to present a full discussion
of the work of Baguant but just to summarise its main findings.
Passenger Mobility
A statistical and mathematical analysis of the historical data revealed that there exists a close exponential relationship between passenger mobility, expressed as passenger-kilometres per capita, and gross domestic product per capita.
The best fit model was identified as Y = Ysat ( 1- ekx ) where
Y is passenger mobility (passenger-kilometre per capita)
X is Gross Domestic Product per Capita ( constant 1980 US dollars)
Ysat is the saturation limit for mobility (10,000 Km per capita per year)
K is a constant found to be -4.27 X 104
The respective values for Ysat
and K respectively were found to give the best model fit.
Freight Mobility
Similar analysis of freight transport revealed a quasi linear relationship between freight mobility (Y) expressed in tonne kilometres per capita and Gross Domestic Product per Capita (X).
The best fit relationship was found to be:
Y = aX - b
where
a = 0.52
b = 26.16
The virtually linear relationship between tonnes-kilometres
per capita and GDP per capita is surprising but can be explained
by the fact that an increase in the economic activity of the country
necessarily brings about a corresponding increase in the tonnage
of goods shipped from one place to the other. Hence a linear relationship.
The evolution of land transport 1993-2010:
Baguant (1996) developed several scenarios ( base
case, favourable and unfavourable) concerning the evolution of
land transport from the 1993 to 2010 period. One of the most significant
factor is bus modal share that presently is 67%. Should that increase
to 84% to the year 2010 then a reduction in total traffic loading
of 23% can be expected and a reduction of 53% in gasoline demand.
In the base case (1993-2010,
the do nothing scenario), the passenger car unit per day (PCU
per day) nearly doubles from 2808 per day to 5367 PCU per day.
The shares from the different modes are:
4 WHR's 41%
Freight 36%
2 WHR's 14%
Bus 9%
Diesel consumption increases by 138% from 116 million
litres to 277 million litres, the share of consumption is passenger
12% and freight 88%.
Gasoline consumption increases by 69% from 93 million
litres to 157 million litres. The share of consumption by 4 Whr's
85% and 2 Whr's 15%.
Emissions of carbon dioxide and lead (in tonnes)
per year
| Year | CO 2 (in tonnes) | Lead (Pb) (in tonnes) |
| 1993 | 28530 | 44 |
| 2010 | 51376 | 74 |
| % Increase over period | 80% | 68% |
Modal Shift:
As said earlier, any shift towards or away from public
transport is expected to have major impacts on traffic loading,
fuel demand and emissions.
Shift to public mode (favourable case)
Traffic loading
PCU/day decrease from 5367 to 4113 representing a 23% reduction.
The share among the different transport modes is
4-Whrs 20%
Freight 47%
2-Whrs 18%
Bus 15%
Fuel Demand
A decrease of 3% for diesel and 53% for gasoline
Emissions
CO2 a decrease of 33%
Lead a decrease of 53%
Shift to private mode (unfavourable case)
Traffic loading
PCU/ day increase by 57% (from 5367 to 8215)
Transport Share
4 Whr's 52%
Freight 24%
2 Whr's 21%
Bus 3%
Fuel Demand
A decrease of 6.5% in diesel, an increase of 102% in gasoline
Emissions
An 82% increase in CO2 and 100% increase in lead.
The increase in gross domestic product and wealth of the country that is foreseeable in the coming decade will inevitably bring about an increase in freight transport and passenger transport. It is crucial that the use of public transport is encouraged if Mauritius is not to face virtually intractable land transport problems. Already journey times from Port Louis to Curepipe have increased by 40% over a ten year period. Though a shift to public transport is highly desirable and necessary, it is far from being sufficient.
The heavy traffic that flows along the Port Louis to Curepipe corridor is, to a great extent, due to the concentration of government departments and business offices in Port Louis. It is high time that government takes the initiative by delocalising some of its departments and ministries. Few government departments really need to be in the city centre. Similarly, government should encourage businesses to move out of Port Louis, it is an aberration that some private firms still have their stores and warehouses in the city centre.
To ease traffic loading, heavy vehicles should be
banned from going in and out of Port Louis at peak times for they
slow down the traffic flow significantly.
But it is the decentralisation of businesses and
government offices that will have the greatest impact on traffic
loading in Mauritius.
Last Update: Thursday, January 22, 1998