SP Arch Inc.

Druid Lake Finished Tanks


The Druid Reservoir (also commonly referred to as Druid Lake) is part of the City of Baltimore public water supply system.  It is a finished water storage facility with a holding capacity, at overflow elevation 214.5 feet, of 364.5 million gallons (mg).  The reservoir receives flow from the Montebello Water Filtration Plant (MWFP) and generally is operated within an elevation range of 205 to 213 feet, and averaging 210 feet.

To comply with the Safe Drinking Water Act (SDWA) Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR), the reservoir must either be replaced with covered storage or the discharge to the distribution system must be treated to achieve the required inactivation of any viruses. The team's analyses comparing storage and treatment options indicated that ultraviolet disinfection was a less expensive option than covered storage, and would minimize disturbance of the lake. However, the Department of Public Works decided to proceed with covered storage system in conjunction with a sodium hypochlorite dosing system for enhanced virus inactivation and residual disinfectant because it was considered the more permanent. In anticipation of the EPA regulations becoming more stringent, the covered storage despite the increased cost was the appropriate solution.

3613 Milford Mill Road                           *                          Windsor Mill, MD 21244                               *                          (443) 565-0432