Cranston, Rhode Island


Joint Venture for Water & Wastewater Treatment

The challenge

When Conoco’s water and wastewater operations partner was in financial difficulty and needing to divest some of its holdings, Veolia purchased its 50% interest in HydroServe Westlake LLC and took over their contract with Phillips 66 at this location. Veolia has been carrying out the remaining 28 years of its predecessor’s 30-year agreement to provide water production and wastewater treatment services to the Conoco refinery.
The 7-MGD surface water treatment plant features lamella clarification, counter current mixed media filtration and chemical addition, while the 7-MGD wastewater treatment facility uses secondary and tertiary processes. This system includes cooling towers, equalization tanks, dual-train activated sludge treatment, clarification and thickening through dissolved air floatation. Wastewater sludge is dewatered using plate and frame presses, compressed air and chemical addition.

The project challenges are:

  • Veolia was challenged to provide water production and wastewater treatment services to Phillips 66, Inc.’s Lake Charles refinery at Westlake.

  • The agreement included the purchase of a 50% interest in HydroServe, LLC – a joint venture with Conoco that includes the ownership of a 3.6MGD surface water treatment plant and a 7-MGD wastewater treatment facility.

  • This is Phillips 66 largest refinery and processes approximately 10% of the lubricating base oil production in the U.S. This project ranks as one of the chemical industry’s largest industrial outsourcing agreements for water and wastewater treatment.

The solution

Innovative solutions:

  • Veolia successfully treats the flow through secondary processes to return the water to discharge quality.

  • Following dual-train activated sludge treatment and clarification, the final effluent is discharged to the river.

  • Sludge is chemically conditioned, thickened through dissolved air floatation, dewatered on a belt and frame press and then landfilled.

Benefits for our clients


  • The Veolia-managed water and wastewater facility at the Westlake complex had a zero recordable incidence rate (with 24,048 hours worked as of 2012) and 13 years with no LTA or RCA.

  • Veolia achieved the “contractor award for meritorious safety performance” awarded by OSHA based on the achievements of employees’ safety records.

  • Veolia successfully minimized their total recordable incident rate for the 2012 calendar year while working over 20,000 hours at each of Conoco’s sites.

  • Veolia’s work in the Conoco/Hydroserve project also received this honor in 2002, 2004, and 2006 through 2012. The remaining 15 year agreement between Veolia and Westlake Chemical is expected to save Conoco $1 million annually in operating costs.