Review of the Bureau of Reclamation’s Corrosion Prevention Standards for Ductile Iron Pipe (NMAB)

Released 01.30.09

Ductile iron pipe (DIP) is commonly used for water transmission and distribution.  In particular, the Bureau of Reclamation makes extensive use of DIP for its large water projects in the Western United States.  As with all pipe materials, DIP is subject to corrosion, the rate of which depends on the characteristics of the soil in which it is placed.  The Bureau has determined corrosion protection requirements for the pipe it uses.  For the most corrosive soil, the most recent requirements issued by the Bureau (2004) have become rather controversial.  The manufacturers of DIP argue the protection required in this case is too stringent, costly, and difficult to apply.  To attempt to resolve this controversy, the Bureau asked the NRC to study the issue and make recommendations about corrosion protection for DIP in highly corrosive soils.  This report presents an overview of DIP and corrosion; an assessment of case histories and data about DIP corrosion performance; an analysis of pipeline failure criteria; an evaluation of corrosion control alternatives; and findings and recommendations.