Saturday, June 16, 2007

Ben Schoeman congestion: whose fault?

Commuters who have to endure the peak-hour congestion on the Ben Schoeman highway between the Brakfontein and Buccleuch interchanges on the N1, or have to take another route between Pretoria and Johannesburg would be forgiven for cursing the traffic authorities.

I think the transport authorities were slow in recognizing and reacting to the problem (and their reaction was perhaps inappropriate - let's see how the Gautrain works out).

The transport authorities also don't react quickly enough in daily traffic. Broken down trucks at peak times often stay stuck for hours, causing huge back-ups, with the authorities being either unable, or unwilling to move them.

But I don't think that the transport authorities are exclusively to blame:
  • It seems like the south-bound lanes are congested in the mornings, and the north-bound lanes in the evenings. A lot of skilled workers are forced to commute from Pretoria and Centurion to Johannesburg because of the dearth of well-paying job opportunities in the Tshwane Metropolitan area. For now a lot of blame has to be apportioned to the municipality (which had a lot of its priorities wrong), and to the commuters themselves, who are perhaps symptomatic of a government-centric, non-entrepreneurial Pretoria mindset. The commercial sector in Centurion seems to be growing, so perhaps things will improve in a few years.
  • Anyone who has driven along the R55 will see that there are massive developments coming up, from Woodmead to Centurion. Who gives zoning permission for these developments in areas where the road network is inadequate? Do the speculators/developers pay rezoning levies? Are the rezoning levies used to improve the road networks? Another example of this is the Samrand area in Centurion, which has one of the most congested interchanges on the Ben Schoeman in the mornings that brings traffic on the freeway to a grinding halt, and the immediate area isn't even heavily developed yet (Samrand has an interesting history). Presumably, a lot of people using the interchange, and clogging the highway up, come from developments in the south of Centurion, which have mushroomed in the last few years.
  • Flexitime (or "semi-flexitime"), which allows individual workers to stagger their working hours is great for individual commuters and it probably reduces peak traffic volumes, but it probably leads to by increasing the number of single-occupant vehicles, since everyone starts and ends at different times. Fully flexible working hours and telecommuting are probably the way of the future, but I don't expect many South African companies to adopt these methods anytime soon (I find South Africa to be rather conservative and uninnovative, but that's another story).
While new lanes should perhaps be added to the Ben Schoeman highway and other measures introduced to cope with existing demand, the government cannot be expected to add new lanes to the highway forever.

Unless zoning laws are enforced, and urban sprawl is brought under control, along with more commercial development in Centurion and Pretoria, I don't see Gauteng's north-south traffic problems ending anytime soon.

Gapminder: Demographic data visualisations

This has been around for a few months, but if you haven't played with it yet, it's worth a look:

Gapminder from Google.

It allows you to visualize various demographic measures. South Africa doesn't do too badly, except on life expectancy, where, like other Southern African countries, the life expectancy has plunged in recent years. To my untrained eye, South Africa's reduced life expectancy doesn't seem to be correlated with economic growth or child mortality, but it may be correlated with per capita income.

Productivity per capita versus life expectancy might also be a revealing measure, but I am not an economist, so I can't think of any way of measuring productivity, or defining it.

Gapminder is a fascinating tool.

If, like me, Gapminder got you interested in data visualization check out the Periodic Table of Visualization Methods.