LFA assisted the City of Mishawaka in development of a Master Plan, design and construction projects in the Milburn Boulevard neighborhood. This area was primarily served by combined sewers constructed in the 1920’s – 1930’s, and has historically experienced basement sewer backups during wet weather events and contributes to two of the City’s combined sewer overflow locations.

The study included flow metering, video inspection of the combined sewers (10± miles), manhole inspections (150±), and geotechnical inspection, including the installation of piezometers and a customer survey regarding basement backups and street drainage. The evaluation of the existing system resulted in a recommendation to construct a separate storm sewer system, groundwater underdrain and rehabilitation of the existing combined sewers to act as a separate sanitary system. The improvements were designed to minimize basement backups and combined sewer overflows, meeting the requirements of the City’s Long Term Plan (LTCP).

As a result, over the last 15+ years, the City has completed thirteen sewer separation and neighborhood improvement projects, one lift station upgrade, two main line CIPP Rehabilitation Projects and three lateral lining CIPP projects. Of these projects LFA has acted as Designer (8 phases), Design Coordinator (6 phases), Construction Inspection (15 phases) and construction oversight when four phases were constructed during a single season. It is estimated that dry weather flows from the Milburn area have reduced by 1.1MGD by removing groundwater infiltration to the sewer system, in addition to removing the wet weather contribution.