Public Works Director Gives Update on Current "Paving the Way" Projects
At the September 14th, 2023, regular meeting of City Council, City of Osawatomie Public Works Director Michele Silsbee provided an update to the governing body regarding the continuing work along Brown Avenue and the partial closing of Main Street. Silsbee noted that both projects, which are interdependent, have experienced a number of unexpected delays as contractors progress through various steps of Brown Avenue’s full-depth reconstruction. She reiterated that the Main Street closure was necessary in order to upgrade storm sewer systems crossing Main Street at the 10th Street and 8th Street intersections. These upgrades are required to accommodate the improved storm sewer infrastructure being installed along Brown Avenue.
A critical issue first arose when contractors and staff revealed the existing storm sewer under Main Street, which was installed in 2018, and discovered that it was not equipped to handle the direct flow from Brown Avenue. In order to achieve the necessary level of service, and to be consistent with current standards for reconstruction projects, upgrades to the infrastructure under and along Main Street became critically required before the rest of the Brown Avenue project could proceed.
Initially, staff estimated the closure of Main Street to last two to three weeks, beginning on August 2nd, 2023, with the scope of work being limited to the replacement of three pipes with larger ones and making minimal adjustments to the existing inlet boxes. However, as contractor Killough Construction began work, an unforeseen engineering design error created a significant obstacle at both the 8th Street and 10th Street intersections. Though the error was quickly identified, subsequent corrections to the plan and engineering redesigns delayed physical progress. Because the work done to this point included open trenches and full-depth saw cuts through the concrete, Main Street remained closed from 7th Street to 12th Street. In considering possible detour routes, Silsbee said it’s important to remember that detours are designed to properly direct the heaviest and largest vehicles that could traverse a community. In this situation, diverting all non-local traffic to Pacific Avenue was the best solution to prevent semi-trucks and other large vehicles from attempting to navigate narrow or crowded residential streets.
Once the revised design was completed by the City’s engineering partners BG Consultants, Killough had to remove a significant portion of 10th Street’s existing inlet box to install the newly designed infrastructure. Rebuilding the existing box was both quicker and cheaper than ordering and installing a brand-new inlet box and, as a result, Main Street from 9th Street to 12th Street was able to be reopened on August 25, 2023. This partial reopening came three and a half weeks after the initial closure.
With work finished at the 10th Street intersection, additional obstacles began to appear at the 8th Street intersection when a conflict with a 10" water main was discovered. This necessitated a more intricate engineering redesign, which was received by staff on September 7th, 2023. During the redesign period, to prevent Killough from having to pull crews off of the Brown Avenue project, focus shifted to the 7th Street storm sewer installation which did not require a Main Street crossing. Gas and fiber line conflicts and limited right-of-way in the work area required Killough to temporarily close 7th Street between Brown Avenue and Main Street to safely maneuver equipment and stage materials. Thanks to careful planning and execution, Killough successfully completed this section with only one overnight closure of 7th Street. It is now fully reopened to all traffic.
As of September 14th, a significant portion of the upgraded storm sewer had been installed at the 8th and Main Street intersection. However, work could not proceed further without the new structures mandated by the final redesign to safeguard the integrity of the 10" water main. Significant changes were required including new inlet boxes, an enlarged manhole, and a series of new pipes.
To account for the redesigns and additional work necessitated at these Main Street intersections, Silsbee also presented two change orders to the City Council on September 14th in the form of a resolution. Change orders are triggered when a contracted project incurs a significant change in scope and can only be approved through action by City Council. The change order for the 10th Street section totaled $8,580.17, and included the purchase of new pipes, increased erosion mitigation, restocking fees for unused structures, and the cost of rebuilding a portion of the inlet box. For the 8th Street section, the change order totaled $38,506.57 and included the additional survey work, three new inlet boxes, three concrete pipes, and a larger manhole. While the structures initially made for this project cannot be returned, the pipe can be restocked.
The original total cost for the Brown Avenue (7th Street to 12th Street) Reconstruction project was $2,777,364.27. The change orders presented to City Council totaled $47,086.74, which represents approximately 1.7% of the project cost and is well below the industry standard (5%-10%) for change orders on projects of this nature. Silsbee explained that due to the issues that necessitated the redesign of both the 10th and 8th Street crossings, $30,000 of the total is being covered by other parties. This has resulted in a decrease of City cost to $17,086.74.
The City’s primary expense in the change order is related to the decision to protect the existing 10" water main at the 8th Street crossing. While the industry standard in similar situations is normally to relocate utilities out of the way of storm sewer and road improvements, staff determined that the better long-term decision for the City was to avoid relocation and maintain the structural integrity of this critical piece of the water distribution system. As a result, staff also determined that the storm sewer design for this intersection has a better capacity and will accomplish a better level of service for the high-traffic intersection.
Silsbee said she and the rest of City staff involved in the project recognize that what was initially scheduled as a two- to three-week closure of Main Street has extended to four weeks of full closure and six weeks and counting of partial closure, and that there have been numerous complaints and concerns from the community. As the City Council considered the resolution to approve the presented change orders, Silsbee asked that councilmembers keep in mind that the delays were driven by the City’s commitment to not only meet the needs of the Brown Avenue reconstruction project but also to ensure into the future a reliable water distribution service to our citizens and hand a better long-term maintenance situation to future staff members.
In closing, Silsbee explained to City Council that the required pipes and structures for the final redesign of the 8th Street crossing were expected to be delivered within approximately one to two weeks. Weather permitting, installation should take approximately one week followed by an additional 10 days for the nearly 10" of concrete to cure. Staff is hopeful for a mid-October reopening if all goes according to plan.
While the unexpected challenges and delays have been far from ideal, Silsbee said she “firmly believe[s] that the decisions made have been in the best interest of our community's long-term well-being.”
After reviewing the information presented by Director Silsbee, City Council voted to approve the resolution and accepted the change orders as presented.
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For additional information on the Brown Avenue project or the Main Street closure, please contact Public Works Director Michele Silsbee or City Manager Bret Glendening. Previous updates regarding the City of Osawatomie's Paving the Way Road Reconstruction Program are available on our website.
Michele Silsbee
Public Works Director
[email protected]
913-755-2146 x 231
Bret Glendening
City Manager
[email protected]
913-755-2146 x 101