1 EXHIBIT 15 The Board of Directors and Shareholders Tidewater Inc. We are aware of the incorporation by reference in the Registration Statements 33-63094, 33-38240, and 333-32729 on Form S-8 of Tidewater Inc. of our report dated October 20, 1997 relating to the unaudited condensed consolidated interim financial statements of Tidewater Inc. that is included in its Form 10-Q for the quarter ended September 30, 1997. Pursuant to Rule 436(c) of the Securities Act of 1933, our report is not a part of the registration statements prepared or certified by accountants within the meaning of Section 7 or 11 of the Securities Act of 1933. ERNST & YOUNG LLP New Orleans, Louisiana October 20, 1997