Aegion Corporation (“Aegion” or the “Company”) (Nasdaq Global Select Market: AEGN) today announced that its subsidiary, Insituform Technologies, LLC (“Insituform”), has been awarded a contract valued at $16 million from the City of Baltimore, Maryland. In total, the City of Baltimore has awarded Insituform $46.4 million in contracts since December 2012. Insituform will install over 170,000 feet of small- and medium-diameter Insituform® cured-in-place pipe (CIPP) in wastewater pipelines located in urban areas in the north and east portions of the city. Approximately 30 percent of the project, including manhole and lateral rehabilitation, spot repairs and restoration, will be performed by minority subcontractors who have been certified through the Maryland Department of Transportation. Work on the project is expected to begin in the third quarter of 2013 and will take approximately 16 months to complete. Jeff Kowal, Vice President and General Manager of Insituform’s East Region, said, “The City of Baltimore is implementing a comprehensive plan to improve a significant portion of its wastewater system. This is a significant undertaking and we are proud to continue to partner with the City on this important effort. We have been working with local subcontractors and minority firms to meet the demands of these projects and to ensure local residents realize the full benefit of these rehabilitation projects. Insituform will continue to pursue future project awards from the City.” About Aegion Corporation Aegion Corporation is a global leader in infrastructure protection, providing proprietary technologies and services to protect against the corrosion of industrial pipelines and for the rehabilitation and strengthening of sewer, water, energy and mining piping systems and buildings, bridges, tunnels and waterfront structures. More information about Aegion can be found on its internet site at www.aegion.com. About Insituform Technologies, LLC For over forty years, Insituform Technologies, LLC, a subsidiary of Aegion Corporation, has been a global leader in the development and installation of proprietary technologies and services for rehabilitating sewer, water and other underground piping systems without digging or disruption. More information about Insituform Technologies can be found on its Internet site at www.insituform.com. Forward-Looking Statements The Private Securities Litigation Reform Act of 1995 provides a “safe harbor” for forward-looking statements. The Company makes forward-looking statements in this news release that represent the Company’s beliefs or expectations about future events or financial performance. These forward-looking statements are based on information currently available to the Company and on management’s beliefs, assumptions, estimates or projections and are not guarantees of future events or results. When used in this document, the words “anticipate,” “estimate,” “believe,” “plan,” “intend,” “may,” “will” and similar expressions are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. Such statements are subject to known and unknown risks, uncertainties and assumptions, including those referred to in the “Risk Factors” section of the Company’s Annual Report on Form 10-K for the year ended December 31, 2012, as filed with the Securities and Exchange Commission on February 28, 2013, and in the Company’s subsequent quarterly reports on Form 10-Q. In light of these risks, uncertainties and assumptions, the forward-looking events may not occur. In addition, the Company’s actual results may vary materially from those anticipated, estimated, suggested or projected. Except as required by law, the Company does not assume a duty to update forward-looking statements, whether as a result of new information, future events or otherwise. Investors should, however, review additional disclosures made by the Company from time to time in its periodic filings with the Securities and Exchange Commission. Please use caution and do not place reliance on forward-looking statements. All forward looking-statements made by the Company in this news release are qualified by these cautionary statements.