A systematic approach to the replacement of an aging distribution system

Cass County Electric Cooperative (CCEC), like many other electric cooperatives, owns, operates, and maintains an aging overhead and a prematurely failing underground primary distribution system. Overhead primary comprises 69% or 3178 circuit miles of CCEC's distribution system. The vast majority of CCEC's overhead primary distribution system was constructed during the 1930s and 1940s, which indicates the system is reaching 50+ years of age. Underground primary cable comprises the remaining 31% or 1436 circuit miles of CCEC's distribution system. Installation of underground primary cable was very prevalent in the 1960s and 1970s at CCEC. However, due to a continuing history of premature cable failures, underground primary cable is now being replaced significantly sooner than the cable's anticipated life expectancy. This paper outlines the systematic approach utilized by Cass County Electric Cooperative to begin replacing its aging overhead and prematurely failing underground primary distribution systems.