The two firms along with Britain's United Utilities will take equity in the Muharraq sewage treatment plant and waste water system project in Bahrain's capital of Manama, Invest AD said in a statement.
Samsung is committing 45 percent, Invest AD 35 percent, and United Utilities 20 percent in the project.
Bahrain's Ministry of Works and Ministry of Finance awarded the concession after evaluating six bids submitted in February last year.
No details on the project's cost or the value of the contract were provided.
The plant will process 100,000 cubic meters per day and is expected to achieve mechanical completion after 30 months.
The project is being debt financed by the Export-Import Bank of Korea, Japanese lender Sumitomo Mitsui Banking and French banks Natixis and Credit Agricole.
