History

NCPI Through the Years

Clay pipe was first introduced in the sewers of Washington DC in 1815. More than 200 years later, there have been significant advances.

The History
Of NCPI

The Path to Standards (1815-1915)

Manufacturing clay pipe in the U.S. didn’t begin until approximately 1849.

The ASTM Committee C04 (originally Committee L) was formed in 1904, and took several years of research to establish “Tentative Specifications for Clay Sewer Pipe,” designated C13-17 T. The focus of this standard was primarily the size, shape and strength of the pipe. There were no design or installation standards.

Anson Marston joined the C04 committee in 1912. Under his leadership, the Memoranda for Recommendations for the Laying of Sewer Pipe was introduced. It was accepted in 1915, 100-years after installations began in the U.S.

The State of Practice (1920s & 1930s)

Metcalf & Eddy published American Sewerage Practice in the early 1920s. At that time 99.3% of the population (in cities of 100,000 or more) used dilution (a.k.a. infiltration and release into large bodies of water) as the only “treatment” for their sewage.

Additional Research & Introduction of the Clean Water Act (1940s - 1970s)

In the early 1940s through the mid1950s, NCPI partnered with the Ohio State University to conduct research into manufacturing methods, testing, and joint design. Following this research, compression joints were introduced and widely accepted by U.S. manufacturers.

In the 1960s and 1970s, NCPI conducted independent research that led to dramatic improvements in pipe strength and significant changes to ASTM C301 Standard Test Methods for Vitrified Clay Pipe.

With the passage of the Clean Water Act in 1972, dilution was no longer a solution. ASTM standards for VCP evolved to require “leak-free” joints.

Trenchless Installation with VCP (1980s & 1990s)

The first trenchless installation of VCP in the U.S. was in 1992 and the first ASTM standard governing the manufacture of Vitrified Clay Jacking Pipe was introduced in 1991. The Pilot Tube Method of Guided Boring (originally called Pilot Tube Microtunneling) was introduced in the U.S. in 1995.

CLSM Creates a New Bedding Class (2000s)

The turn of the 21st century saw NCPI conducting research into the optimal mix design and use of CLSM (Controlled Low-Strength Material) as a bedding material. The successful tests resulted in the introduction of a new bedding class with a load factor of 2.8.

Haunching (2010s)

Partnering with soil and pipeline installation expert Amster Howard, NCPI conducts research into Haunch Support of pipe embedment. The findings of the research led to new educational materials for installers and inspectors ensuring proper installation with uniform circumferential support to create reliable field supporting strength for the final pipeline.

The First Cleaning Standard (2020s)

ASTM C1920 Standard Practice for Cleaning of Vitrified Clay Sanitary Sewer Pipelines was introduced. VCP became the first pipe material to publish a cleaning standard.

Today, NCPI continues its primary mission of research and education.