Storm Drainage: Flexible or Rigid Pipe Systems

That is the question, isn’t it?

If you're designing a new stormwater system, what are your options?

Traditionally, there have been two primary choices for drainage pipe systems.

The first is Reinforced Concrete Pipe (RCP), commonly known as concrete pipe. This is considered a rigid pipe system. I often describe it as an underground horizontal structure because of the way it carries loads and maintains its shape.

RCP consists of two key components. The first is a dry-cast concrete mix designed for strength and durability. The second is a steel reinforcement cage embedded within the concrete. This steel reinforcement significantly enhances the structural integrity of the pipe, allowing it to withstand substantial loads over its service life.

The second option is a flexible pipe system. Unlike concrete pipe, flexible pipe is typically manufactured from high-density polyethylene (HDPE) and features an exterior corrugated design.

Those corrugations allow compacted soil to fill the spaces around the pipe, creating a soil envelope that contributes to the pipe's overall strength. In a flexible pipe system, the surrounding soil and the pipe work together structurally. As the soil moves, the pipe is designed to flex with it. In certain applications and site conditions, that flexibility can be a significant advantage.

In a future discussion, we'll explore other storm drainage products, including several semi-rigid pipe options available in today's market.

For now, I simply want to leave you with this understanding:

When it comes to stormwater infrastructure, the choice often comes down to two fundamental categories—rigid pipe systems and flexible pipe systems.

That is the question.

Which one will you choose?

If you have questions about your next project, let's start the conversation.

~ Wayne Atkinson