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Note 1 - Organization | 12 Months Ended
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Dec. 31, 2018
Notes to Financial Statements |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] |
1. | ORGANIZATION :
Northwest Pipe Company (collectively with its subsidiaries, the “Company”) operates in one business segment, Water Transmission, which produces steel pipeline systems, as well as reinforced concrete pipe and protective linings, primarily for use in drinking water infrastructure and has manufacturing facilities located in Portland, Oregon; San Luis Río Colorado, Mexico; Adelanto, California; Saginaw, Texas; Tracy, California; Parkersburg, West Virginia; St. Louis, Missouri; and Brea, California.

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