Client – St. Charles County PWSD No. 2

Cochran provided survey and civil design services for St. Charles County PWSD #1.  We performed the study and design of a complete 0.25 MGD membrane bioreactor (MBR) wastewater treatment facility, which will be expandable to 1.0 MGD.  The project also required installation of approximately 4.75 miles of 8 to 12 inch diameter sewer main for a 380 lot subdivision.  The lift station is sized to serve 112 lots and 1 elementary school.  Cochran also completed a receiving stream impact study.  We designed for future ultraviolet disinfection at a peak flow rate of 4 mgd.  Cochran also designed mechanical, electrical and structural aspects.  The facility utilizes flat panel membrane technology to meet effluent design limits of 10 mg/L BOD and 15 mg/L TSS.  The facility design includes a laboratory to perform required self-monitoring analytical work and process control tests for all treatment processes.