The City of Sulphur Regional Wastewater Treatment Facility is located at 3400 Bayou D'Inde Road, Westlake La 70669.  The system serves regional areas including Sulphur, Westlake, Carlyss, Mossville. There are eleven employees at the plant who monitor, operate and maintain an in-house analytical laboratory, process and operations of plant and grounds, and pump lift stations.  Staff is Level 4 certified in Wastewater treatment and Wastewater collections and highly capable.

In 1985 a Return Activated Sludge Process Plant was put into operation.  It was operated for over 20 years. The process was used efficiently for many years, but as the population and incorporation increased it was found that it greatly needed to be upgraded. 

In March 2008, a new wastewater system was put into operation. The new process utilizes a SBR (Sequencing Batch Reactor) 4 Basin System with a design flow of 9.0 MGD with the capability and capacity to handle a maximum of 27 MGD. Since its inception, the quality and operational values of our final product has greatly improved.

The new system consists of a Pista Grit Removal chamber, an automated screenings removal system, and the four multi-sequence reactors.

The final treatment system utilizes an equalization basin for flow control, four tertiary filters for residual solids removal, ultraviolet light disinfection system, and 2 sludge dewatering presses for final sludge disposal.

The City Wastewater Treatment Department maintains and operates 32 pumping liftstations located throughout the City to collect and deliver the wastewater into the wastewater plant.  

The Wastewater Plant and Liftstations are monitored by a computer alarm monitoring system for off duty hours and weekends.