Franz Environmental has annual gross revenues of CA$20m (£10.8m).
Arcadis - which is also in the process of buying Hyder- said that Franz's specialised expertise in environmental remediation, site assessments, brownfields, and hydrogeology will complement its own services in the region.
The acquisition of Franz comes shortly after that of Senes last year, and brings Arcadis staff numbers in Canada to about 360.
"Franz's environmental expertise in the Canadian federal, municipal and private sectors will further enhance the support we provide our clients in North America and beyond," said Gary Coates, CEO of Arcadis North America. "Together we strengthen our leadership position to solve our clients' most complex environmental problems, adding depth to our existing on-site teams and expanding to new territories."
Thomas Franz, CEO of Franz, added: "Franz has grown by leaps and bounds since it was founded in 2000 and joining forces with Arcadis marks the next great chapter in our history. Arcadis' technical expertise complements that of Franz, and our clients will undoubtedly benefit from Arcadis' deep resources and knowledge."