Flooding Mitigation in Moline, for 1/3 the Expected Cost!

A $150,000 storm sewer replacement project was completed to mitigate local flooding issues due to collapsed and undersized storm sewer running through the Cloverleaf Village Manufactured Home Community.  The existing pipe had failed and ponding from the upstream wetlands area was flooding the park.  The project included 650’ of 30” RCP storm sewer, installed between two wetland areas.  The pipe is located in the middle of a residential neighborhood and a safety apron and grate was installed on the upstream end to mitigate the potential for children to become trapped in the sewer.  The new pipe was installed along the existing sewer’s alignment due to the tight work area.  Due to the wetlands at each end of this storm sewer project, permitting through the City of Moline, the Illinois Department of Natural Resources and the Army Corp of Engineers was required.

The project was bid and awarded to a local contractor and completed in September 2020.  In addition to the design and permitting work associated with the project, Clearwell prepared bid documents, let the project, provided a review and comparison of received bids.  Clearwell provided construction observation and reviewed/recommended approval of pay applications from the contractor.

Initial contractor proposals estimated the cost of the proposed improvements at $450,000.  After Clearwell evaluated the existing condition, it was determined that many of the initially proposed improvements would not provide the benefit desired.  A revised approach was recommended and approved by the community owner, which addressed the concerns and saved approximately $300,000 in the process.