NORTHWEST PIPE CO

Evaluation of Disclosure Controls and Procedures

Disclosure controls and procedures (as defined in Rules 13a‑15(e) and 15d‑15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) are designed to provide reasonable assurance that information required to be disclosed in reports we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the rules and forms of the Securities and Exchange Commission and that such information is accumulated and communicated to our management, including our Chief Executive Officer (“CEO”) and Chief Financial Officer (“CFO”), as appropriate, to allow timely decisions regarding required disclosures.

In connection with the preparation of this Quarterly Report on Form 10‑Q for the quarter ended March 31, 2024, our management, under the supervision and with the participation of our CEO and CFO, evaluated the effectiveness of the design and operation of our disclosure controls and procedures as of March 31, 2024. As a result of the assessment, our CEO and CFO have concluded that, as of March 31, 2024, our disclosure controls and procedures were effective.

Changes in Internal Control over Financial Reporting

There were no significant changes in our internal control over financial reporting that occurred during the quarter ended March 31, 2024 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.