Background/Discussion
The area of East Manawa is very flat with open ditches. There are no storm sewers in this area and the streets are thin asphalt or seal-coated rock roads. During rainfall events, considerable surface ponding occurs due to the poor drainage.
Due to the narrow right-of-way (30 ft.) and the high water table in the area, conventional storm sewer construction is not practical. The use of porous pavement in conjunction with a drainable granular base and shallow subdrain/conveyance system was determined to be the most cost effective means available to improve the area drainage.
The rehab program also includes installation of new sanitary sewers utilizing a vacuum system.
Phase IX includes extending the vacuum sewer along the west side of Navajo Street from just south of Huron Circle to south of Victor Street and reconstruction of East Navajo Street from Victor to Huron Circle.
During execution of the project, it was discovered that additional quantities are required to complete the work. These quantities are in Division IV – Sanitary Sewer. The additional quantities are an increase to existing bid items already in the contract. The Engineer (EGA) did not include these quantities as part of the original bid.
The revised total for the project will be $917,180.12, including C.O. #1. This amount shall be considered the new contract amount for the project.
This project was included in the FY21 CIP and includes a budget of $1,000,000 in Sales Tax Funds.