Concrete pipe has a well established history and reputation for being a long lasting, serviceable material. The Cloacae Maxima, built in about 180 B.C. as part of Rome's main sewer system, was constructed mainly of stone masonry and natural cement concrete. More than 2,000 years later, portions of the concrete sewer are still in use.

Modern day concrete pipe sewer systems emerged during the mid-19th century when the public became conscious of the need for sanitation to control the spread of disease. The earliest recorded use of concrete pipe in the United States is a sewer installation built in 1842 at Mohawk, N.Y. Other New England cities followed suit and installed concrete pipelines in the second half of the nineteenth century. Many of these concrete pipelines are still in use today.

Milestones in concrete pipe development include the production of the first reinforced concrete pipe in 1905, the invention of prestressed concrete pipe in the 1930s, and the manufacture of the first steel-cylinder prestressed concrete pipe in 1942.

Concrete pipe comes in many shapes and sizes. Concrete pipe sizes can range from four inches up to 17 feet in diameter. Although concrete pipe can be manufactured in a variety of shapes, there are five standard shapes: circular, horizontal elliptical, vertical elliptical, arch, and rectangular. The pipe shape selected for a project depends on the topography of the site, importance of hydraulic and structural efficiency, erosion and deposition in the stream channel, and cost. Most often, the preferred pipe shape is the one that will alter the natural drainage flow the least.

Five Methods

As with all concrete products, the basic materials of concrete pipe are portland cement, aggregate, and water. There are five basic methods of producing concrete pipe. Four methods-centrifugal/spinning, dry cast, packerhead, and tamp-entail using a dry concrete mix. The fifth method, wet casting, uses a high-slump concrete mix. Wet-cast concrete mix usually has a slump less than four inches and is most frequently used for manufacturing large diameter pipe.

Concrete pipe serves as a conduit material for irrigation, water supply lines, sanitary sewers, culverts, and storm drains. Culverts, usually made with arch-shaped concrete, are used to carry water under highways in non-urban areas. Storm drain systems for cities and towns are becoming more important as communities become larger and more densely populated. Recent major floods and the resulting damage only emphasize the need for efficient drainage systems.

Subsurface drainage carries away water below the surface of the pavement. This water reduces flow support capacity of the base and subgrade material causing potential damage to roads, airport runways, and building foundations. Many farm fields depend on proper underground drainage for their cultivation. Thousands of square miles of otherwise arid land rely on concrete irrigation pipe to supply water for farmland. Additionally, most of the large cities in the United States a concrete pipe system to transport their water supply.

More information at the American Concrete Pipe Association Web site.