Arcadis NV — Regulatory Filings 2011

Sep 28, 2011

ARCADIS NV Gustav Mahlerplein 97-103 Postbus 7895 1008 AB Amsterdam Tel 020 2011 011 www.arcadis.com

PRESS RELEASE

ARCADIS AWARDED \$30M ENVIRONMENTAL CLEANUP PROJECT FOR PUBLIC UTILITY IN THE WESTERN U.S.

September 28, 2011 – ARCADIS (EURONEXT: ARCAD), the international consultancy, design, engineering and management services company, announced today that it has signed a \$30 million contract with a Western U.S. public utility to clean up a 100-acre site containing tens of thousands of cubic yards of sediments. In addition to removal of legacy material from the site, this project offers several community benefits such as restoration of tidal wetlands, opportunities for local jobs and beneficial reuse of the property as parkland and open space when work is complete.

ARCADIS, in close collaboration with its client, will use sustainable practices and proven technologies to remove and dispose of material off-site, quickly driving the project to completion. The project team will regularly monitor air, noise and traffic to minimize disruption to local roadways and adjacent neighborhoods, maintaining company-wide health and safety standards throughout the project.

Steve Blake, CEO of ARCADIS U.S., expressed: "This project allows ARCADIS to implement best practices in site cleanup, and the larger implications of the project will reach beyond the immediate task at hand. In only a year and a half, tidal wetlands will be restored within a significant ecosystem, air and water quality will improve and the property will be given a second chance at productive use. We are grateful for this opportunity to partner with our client in creating balance between the built and natural environment."

For more information, please contact Joost Slooten of ARCADIS at +31-202011083 or outside office hours at +31-627061880 or e-mail joost.slooten@arcadis.com

About ARCADIS:

ARCADIS is an international company providing consultancy, design, engineering and management services in infrastructure, water, environment and buildings. We enhance mobility, sustainability and quality of life by creating balance in the built and natural environment. ARCADIS develops, designs, implements, maintains and operates projects for companies and governments. With 16,000 employees and over €2 billion in revenues, the company has an extensive international network supported by strong local market positions. ARCADIS supports UN-HABITAT with knowledge and expertise to improve the quality of life in rapidly growing cities around the world. Visit us at: www.arcadis.com.