City of ElkhartELKHART, Ind. -- The Oakland Avenue underpass will close beginning on Tuesday so crew can complete the next phase of a federally mandated sewer separation project. The City of Elkhart says these improvements will help reduce sewage overflows during heavy rain. Officials say it will also protect local rivers and improve the community's water quality. The detour route includes Nappanee Street underpass, Benham Avenue underpass, and Prairie Street overpass.