Collapsible wood form for cast-in-place concrete pipe.

Source: Harold E. Babbitt, Sewerage and Sewage Treatment, 6th edition (New York: John Wiley and Sons, 1949), p. 228.

Typical early sewer cross-sections.

Source: Harold E. Babbitt, Sewerage and Sewage Treatment, 6th edition (New York: John Wiley and Sons, 1949), p. 63.

Typical early sewer cross-sections.

Source: Harold E. Babbitt, Sewerage and Sewage Treatment, 6th edition (New York: John Wiley and Sons, 1949), p. 64.

Gravity outfall sewer, concrete invert up to spring line, multiple-layer brick arch forms the crown. Wood falsework holds up brick arch during construction. Utah, date unknown.

Source: Utah State Historical Society, Photo no. C-601 #1670. Used by permission, Utah State Historical Society, all rights reserved.

Lowering concrete sewer pipe lined with clay liner plates into trench. Date unknown.

Source: National Clay Pipe Institute.

Incinerated ash from sewage sludge is close to the component of clay used in making cement. Therefore, the cement is used in secondary concrete products such as concrete manholes and pipes. Japan, circa 2002.

Source: Making Great Breakthroughs - All about the Sewage Works in Japan (Japan Sewage Works Association: Tokyo, ca. 2002), p. 31.