| As Of | Filing | | Doc. | | Page | | Title | Docs. |
|---|
| | |  |
| 11/21/23 | | S-3 | | | | 1 | | About Northwest Pipe Company | 1 |
| | | | | | 1 | | About This Prospectus | 1 |
| 4/25/24 |  | DEF 14A | | | | 1 | | Additional Information | 2 |
| | | | | | 1 | | Audit Committee Report | 2 |
| | | | | | 1 | | Board Composition | 2 |
| | | | | | 1 | | Board Leadership Structure and Risk Oversight | 2 |
| | | | | | 1 | | Board of Directors Committees | 2 |
| | | | | | 1 | | Board of Directors Meetings | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Business | 1 |
| | | | | | 1 | | Cautionary Statement Regarding Forward-Looking Statements | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Certain Relationships and Related Transactions | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Certain Relationships and Related Transactions, and Director Independence | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Change in Control Agreements | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Changes in and Disagreements With Accountants on Accounting and Financial Disclosure | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Communications with Directors | 2 |
| | | | | | 1 | | Company Culture | 2 |
| | | | | | 1 | | Compensation Committee Interlocks and Insider Participation | 2 |
| | | | | | 1 | | Compensation Committee Report | 2 |
| 8/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Balance Sheets as of June 30, 2023 and December 31, 2022 | 1 |
| 5/4/23 | | 10-Q | | | | 1 | | Condensed Consolidated Balance Sheets as of March 31, 2023 and December 31, 2022 | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Balance Sheets as of September 30, 2023 and December 31, 2022 | 1 |
| | | | | | 1 | | Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2023 and 2022 | 1 |
| 8/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Cash Flows for the six months ended June 30, 2023 and 2022 | 1 |
| 5/4/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2023 and 2022 | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Comprehensive Income for the three and nine months ended September 30, 2023 and 2022 | 1 |
| 8/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Comprehensive Income for the three and six months ended June 30, 2023 and 2022 | 1 |
| 5/4/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Comprehensive Income for the three months ended March 31, 2023 and 2022 | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2023 and 2022 | 1 |
| 8/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Operations for the three and six months ended June 30, 2023 and 2022 | 1 |
| 5/4/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Operations for the three months ended March 31, 2023 and 2022 | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Stockholders' Equity for the three and nine months ended September 30, 2023 and 2022 | 1 |
| 8/3/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Stockholders' Equity for the three and six months ended June 30, 2023 and 2022 | 1 |
| 5/4/23 | | 10-Q | | | | 1 | | Condensed Consolidated Statements of Stockholders' Equity for the three months ended March 31, 2023 and 2022 | 1 |
| 3/5/24 | | 10-K | | | | 1 | | Consolidated Balance Sheets as of December 31, 2023 and 2022 | 1 |
| | | | | | 1 | | Consolidated Statements of Cash Flows for the years ended December 31, 2023, 2022, and 2021 | 1 |
| | | | | | 1 | | Consolidated Statements of Comprehensive Income for the years ended December 31, 2023, 2022, and 2021 | 1 |
| | | | | | 1 | | Consolidated Statements of Operations for the years ended December 31, 2023, 2022, and 2021 | 1 |
| | | | | | 1 | | Consolidated Statements of Stockholders' Equity for the years ended December 31, 2023, 2022, and 2021 | 1 |
| | | | | | 1 | | Controls and Procedures | 4 |
| 4/25/24 | | DEF 14A | | | | 1 | | Corporate Governance | 2 |
| | | | | | 1 | | Creating Stakeholder Value | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Cybersecurity | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Date for Submission of Shareholder Proposals | 2 |
| 11/21/23 | | S-3 | | | | 1 | | Description of Capital Stock | 1 |
| | | | | | 1 | | Description of Debt Securities | 1 |
| | | | | | 1 | | Description of Units | 1 |
| | | | | | 1 | | Description of Warrants | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Director Compensation | 2 |
| | | | | | 1 | | Director Elections | 2 |
| | | | | | 1 | | Director Independence | 2 |
| | | | | | 1 | | Director Skills and Qualifications | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Directors, Executive Officers and Corporate Governance | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Disclosure of Fees Paid to Independent Registered Public Accounting Firm | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Disclosure Regarding Foreign Jurisdictions that Prevent Inspections | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Elements of Compensation | 2 |
| | | | | | 1 | | Employment Agreements | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Executive Compensation | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Executive Compensation and Risk | 2 |
| | | | | | 1 | | Executive Compensation Discussion and Analysis | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Exhibit and Financial Statement Schedules | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Exhibits | 3 |
| 11/21/23 | | S-3 | | | | 1 | | Experts | 1 |
| 3/5/24 | | 10-K | | | | 1 | | F-1 | 1 |
| | | | | | 1 | | F-3 | 1 |
| | | | | | 1 | | F-33 | 1 |
| | | | | | 1 | | F-4 | 1 |
| | | | | | 1 | | F-5 | 1 |
| | | | | | 1 | | F-6 | 1 |
| | | | | | 1 | | F-7 | 1 |
| | | | | | 1 | | F-9 | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Financial Information | 3 |
| | | | | | 1 | | Financial Statements (Unaudited) | 3 |
| 3/5/24 | | 10-K | | | | 1 | | Financial Statements and Supplementary Data | 1 |
| | | | | | 1 | | Form 10-K Summary | 1 |
| 11/21/23 | | S-3 | | | | 1 | | Forms of Securities | 1 |
| | | | | | 1 | | General Description of Securities We May Sell | 1 |
| | | | | | 1 | | Information Incorporated by Reference | 1 |
| | | | | | 1 | | Legal Matters | 1 |
| 3/5/24 | | 10-K | | | | 1 | | Legal Proceedings | 4 |
| 11/3/23 | | 10-Q | | | | 1 | | Management ' s Discussion and Analysis of Financial Condition and Results of Operations | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Management's Discussion and Analysis of Financial Condition and Results of Operations | 2 |
| | | | | | 1 | | Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities | 1 |
| | | | | | 1 | | Mine Safety Disclosures | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Nominees and Continuing Directors | 2 |
| 11/3/23 | | 10-Q | | | | 1 | | Notes to Condensed Consolidated Financial Statements | 3 |
| 3/5/24 | | 10-K | | | | 1 | | Notes to Consolidated Financial Statements | 1 |
| | | | | | 1 | | Other Information | 4 |
| 4/25/24 | | DEF 14A | | | | 1 | | Other Matters | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Part I | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Part I -- Financial Information | 3 |
| 3/5/24 | | 10-K | | | | 1 | | Part II | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Part Ii -- Other Information | 3 |
| 3/5/24 | | 10-K | | | | 1 | | Part III | 1 |
| | | | | | 1 | | Part IV | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Pay Ratio Disclosure | 2 |
| | | | | | 1 | | Pay Versus Performance | 2 |
| 11/21/23 | | S-3 | | | | 1 | | Plan of Distribution | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Potential Payments Upon Termination or Change in Control | 2 |
| 11/21/23 | | S-3 | | | | 1 | | Powers of Attorney (included in signature page in Part II of the Registration Statement) | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Pre-approval Process | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Principal Accountant Fees and Services | 1 |
| | | | | | 1 | | Properties | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Proposal #1: Election of Directors | 2 |
| | | | | | 1 | | Proposal #2: Advisory Vote on Executive Compensation | 2 |
| 4/27/23 | | DEF 14A | | | | 1 | | Proposal #3: Advisory Vote on the Frequency of Shareholder Advisory Votes on Executive Compensation | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Proposal #3: Ratification of the Appointment of Moss Adams LLP | 1 |
| 4/27/23 | | DEF 14A | | | | 1 | | Proposal #4: Ratification of the Appointment of Moss Adams LLP | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Proxy Summary | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Quantitative and Qualitative Disclosures About Market Risk | 4 |
| 4/25/24 | | DEF 14A | | | | 1 | | Questions and Answers About the Proxy Materials and the Annual Meeting | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Report of Independent Registered Public Accounting Firm (Moss Adams LLP, Portland, Oregon, PCAOB ID No. 659 ) | 1 |
| | | | | | 1 | | Reserved | 1 |
| | | | | | 1 | | Risk Factors | 5 |
| | | | | | 1 | | S-1 | 1 |
| | | | | | 1 | | Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters | 1 |
| 11/3/23 | | 10-Q | | | | 1 | | Signatures | 3 |
| 11/21/23 | | S-3 | | | | 1 | | Special Note Regarding Forward-Looking Statements | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | Stock Owned by Management and Principal Shareholders | 2 |
| | | | | | 1 | | Summary Compensation | 1 |
| | | | | | 1 | | Table of Contents | 7 |
| | | | | | 1 | | Transforming Initiatives | 2 |
| 3/5/24 | | 10-K | | | | 1 | | Unresolved Staff Comments | 1 |
| 11/21/23 | | S-3 | | | | 1 | | Use of Proceeds | 1 |
| 3/5/24 | | 10-K | | | | 1 | | Valuation and Qualifying Accounts | 1 |
| 11/21/23 | | S-3 | | | | 1 | | Where You Can Find More Information | 1 |
| 4/27/23 | | DEF 14A | | | | 1 | | 2022 Annual Report | 1 |
| | | | | | 1 | | 2022 Performance Highlights | 1 |
| 4/25/24 | | DEF 14A | | | | 1 | | 2023 Annual Report | 1 |
| | | | | | 1 | | 2023 Performance Highlights | 1 |
