Which of the following types of pipe comes in diameters as large as 168 inches (14 feet)?

Reinforced concrete pipe is known for its ability to be manufactured in very large diameters, up to 168 inches (14 feet) or even more. This capability makes it particularly useful in large-scale projects, such as stormwater systems, sewer systems, and water transmission lines, where substantial volumes of water need to be handled.

The use of reinforced concrete pipe is advantageous due to its strength and durability, allowing it to withstand significant loads and environmental pressures. This makes it suitable for various applications in water distribution and sewage systems.

In contrast, other types of pipe such as cast iron, ductile iron, and prestressed concrete generally do not have the same capacity for large diameter production. For example, while cast-iron and ductile iron pipes are widely used and can handle high pressure, they typically come in smaller diameters and can be more challenging to install as the size increases. Prestressed concrete pipes, while robust, are often used in specific applications and may not reach the same sizes as reinforced concrete pipes. Hence, reinforced concrete pipe is the clear choice for larger diameter necessities in water distribution systems.