The $US 2.85bn equity value will be paid 60% in cash and 40% in Jacobs common stock. Jacobs says it expects the deal to generate $US 150m in cost synergies.

The transaction is expected to close in the first quarter of the 2018 financial year, subject to the approval of regulators and CH2M shareholders.

Jacobs employs more than 54,000 people in 25 countries around the world, while CH2M has more than 20,000 staff and generated revenues of $US 4.4bn over the last year.