Civil Engineering: Traffic Problems in History

All roads lead to Rome . . .

 The Romans built a huge network of roads. They were primarily for military use, but also used for trade. In all, the Romans built over 50,000 miles of hard-surfaced roadway.

Before the roads were paved, the weather could slow down any kind of travel. Rain could wash away sections of road, flood areas, or turn highways into mud bogs after many feet trampled the soggy path.

In those days, you had to walk most places – imagine getting your best pair of Corinthian leather Birkenstocks stuck in a mud hole halfway from home!

"Where we're going, we don't need roads . . ."

In Italy, the engineers developed a form of concrete, made from volcanic ash and lime. They used this to build roads that were strong, straight, and cambered, to allow the rain to run off.

In Pompeii, the roads had other “modern” designs built in. They had crosswalks that were raised, so pedestrians could stay out of the mud. They also used white stones as reflectors, placed at regular intervals down the center of the road. These were bright enough to catch the light from the carriages.

That's a raised crosswalk, so pedestrians didn't have to walk in the dirty streets.
The wagon and chariot wheels were standard widths, so they could pass between the gaps in the stone.

A cross section of Roman street design, from:  A Dictionary of Greek and Roman Antiquities. London: J. Murray.

The general appearance of such a metalled road and footway is shown in an existing street of Pompeii.
(A). Native earth, levelled and, if necessary, rammed tight.
(B). Statumen: stones of a size to fill the hand.
(C). Audits: rubble or concrete of broken stones and lime.
(D). Nucleus: kernel or bedding of fine cement made of pounded potshards and lime.
(E). Dorsum or agger viae: the elliptical surface or crown of the road (media stratae eminentia) made of polygonal blocks of silex (basaltic lava) or rectangular blocks of saxum qitadratum (travertine, peperino, or other stone of the country). The upper surface was designed to cast off rain or water like the shell of a tortoise. The lower surfaces of the separate stones, here shown as flat, were sometimes cut to a point or edge in order to grasp the nucleus, or next layer, more firmly.
(F). Crepido, margo or semita: raised footway, or sidewalk, on each side of the via.
(G). Umbones or edge-stones.

Today most of the top layer of concrete has eroded, leaving the bumpy looking pavers on top, but at the time, these roads were smooth and fast.

Civil Engineering: Traffic Calming

What is a Woonerf?

www.hea-inc.com

In the U.S. they are sometimes called "Complete Streets."

They are areas that is shared by vehicles, cyclists, and pedestrians. The word for "Woonerf" (Pronounced "Vu-nerf") is loosely translated "Living Street."

The idea is to create a space where drivers feel more cautious, naturally slowing down and keeping particular watch for pedestrians and cyclists. The way this is accomplished is by making the driver feel out of place. In a "Complete Street," the boundaries between vehicle right-of-way and the right of way of other traffic is blurred, instinctively causing the drivers to become more alert.

Often these areas are used for city events, or around parks.

Medford Commons, the new center for Street Fairs

One way to cause the drivers to slow down and pay attention is to make them navigate around planters and bends in the road. By putting obstacles in their path, drivers have to exercise more caution when driving, but the visibility is still good for avoiding pedestrians.

A Woonerf design by Hardey Engineering and Assoc.

Using Permeable Pavers

Another way to cause traffic to calm down is to blend the transition between the vehicle right-of-way and the pedestrian right-of-way. In this example, Hardey Engineering & Assoc. used permeable pavers in the road, so that it looks the same as the adjacent sidewalk. The creates the effect of having a crosswalk that is an entire block in length.

5th Street looks similar to the Sidewalk

Another advantage to using pavers in the street is that the texture of the street makes the driver feel as though they are travelling faster. Between the tactile feedback of the tires rolling across the pavers, to the visual effect of having a textured surface moving towards you, the driver has a better sense of how fast they are really travelling.

Right now, the Medford 2013 Pear Blossom Event is just kicking off, so I'm going to head down to the inaugural street fair and go and enjoy my rights as a pedestrian in our very own woonerf system!