Mattoon South 9th Street Drainage Improvements

Overview:
TWG provided professional engineering services for the South 9th Street Drainage Project in the City of Mattoon, Illinois. The project consisted of reconstructing diversion and roadway ditches, along with culvert improvements from South 9th Street to the Illinois Central Railroad tracks. These improvements were designed to alleviate flooding in residential areas adjacent to the corridor.

What TWG Delivered:

– Topographic survey
– Right-of-way plat preparation
– Hydrologic and hydraulic drainage analyses utilizing HEC-HMS and HEC-RAS Unsteady Flow
– Contract document preparation
– Coordination of approvals with IDNR, IHPA, and USACE
– Utility relocation coordination

Results:
The completed improvements significantly enhanced stormwater conveyance through the corridor, reducing localized flooding and improving drainage performance for nearby residential properties. The project helped mitigate long-standing drainage concerns for the City while supporting safer and more reliable roadway and neighborhood conditions during storm events.