Agenda Date: 04/01/2025
Subject:
Title
Resolution 33-2025: Approving an amendment to the Intergovernmental Agreement between the City of Littleton and the Colorado Department of Transportation for reimbursement of costs associated with the South Windermere Street over High Line Canal bridge
Body
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From: |
James L. Becklenberg, City Manager |
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Prepared by: |
Brent Soderlin, Director of Public Works & Utilities |
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Kimberly Dall, Assistant City Engineer |
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Presentations: |
N/A |
PURPOSE:
Does city council support amending the Intergovernmental Agreement (IGA) between the City of Littleton and the Colorado Department of Transportation (CDOT) for reimbursement of costs associated with the South Windermere Street over High Line Canal bridge to terminate the current IGA?
LONG-TERM OUTCOME(S) SERVED:
Safe Community; High-Quality Governance
DISCUSSION:
The Windermere bridge crossing the High Line Canal was determined to need replacement based on condition assessments performed in 2021. In 2022, Littleton was awarded a federally funded grant to replace the bridge. An IGA with CDOT was approved by Resolution 54-2021 authorizing the grant funding. City staff solicited the services of Theorem Design Group, (TDG) for design services for the Windermere Street Bridge Replacement Project.
TDG proceeded with the preliminary design of the structure and preparation of the structural selection report for CDOT review. As the project progressed from preliminary to final design, the project team encountered challenges with Historic Preservation review, as well as utility conflicts and potential private property impacts.
Historic Preservation had supported the three-cell structure proposed in the preliminary design. Several months later, Historic Preservation withdrew their support of the three-cell structure, stating the new structure caused an adverse impact to the High Line Canal. The options to proceed with the project were:
1. Work with CDOT staff on an alternatives analysis to determine the design that is the "least harm" to the historic resource.
2. Keep the three-cell design and remove the federal money by switching out with a state funded project. No state projects were identified that would be eligible for a funding swap; additionally, the requirements for each grant program would need to be met for the swapped projects.
3. Keep the three-cell design and fully fund the project without the grant; the federal requirements would no longer apply to the project.
In consideration of the required resources needed to support the grant, the uncertainty of and increases to project costs for selection, design, and construction of the preferred structure, and impacts to project schedule, staff recommended that Littleton forego the federal grant funding. That recommendation was supported by the city manager’s office.
The action before council will amend the IGA with CDOT to reduce the grant funding from $1.2M to $0. No work eligible for grant funding has been expended to date.
BACKGROUND:
The Windermere Bridge Project will replace the structurally deficient bridge crossing the High Line Canal on Windermere Street. The project was awarded grant funding in 2021; the $1.2M grant is fully federally funded and managed by CDOT, requiring all design and construction to adhere to state and federal funding requirements.
Staff hired the consultant firm Theorem Design Group (TDG) to advance the project design to the Field Inspection Review (FIR) (30%) with CDOT. The structure recommended by the design team at the FIR review in November 2022 was a three-cell box culvert modified to preserve the existing canal shape. The FIR review evaluates environmental impacts, including historic preservation. The FIR comments received from Historic Preservation highlighted several historic items to be addressed, including the view corridor of the High Line Canal, trees along the canal, and the profile of the High Line Canal Trail as it crosses Windermere Street. A discussion with the CDOT historian at the time indicated that they could support a No Adverse Effect finding should comments be properly addressed and documented in a report. Resolving the comments could impact the structure selection; TDG and staff committed to address the comments from Historic Preservation prior to advancing the design to 90%.
Several meetings and coordination between TDG, CDOT, and city staff have occurred to help identify the elements needed for Historic Preservation to support a finding of No Adverse Effect for the three-cell box culvert design. Based on the discussions, a complete packet of exhibits and matrix of all Historic Preservation comments was submitted to CDOT in December 2023 for review. Staff, TDG, CDOT, and Historic Preservation met in January 2024, at which time Historic Preservation unexpectedly changed direction and stated they would not support a recommendation of No Adverse Effect for the three-cell box culvert. Their primary justification was that the walls of the culvert cells were a detriment to the visual integrity of the canal, despite the existing bridge having columns in the canal and the opening for the proposed structure being almost identical to the existing bridge opening. Historic Preservation commented that a single span structure or other alternative design would need to be evaluated to progress with the federally funded project. TDG and Littleton staff pointed out that all designs will impact the trees, trail, and view corridor to some extent and the box culvert option was the least impactful to those elements. Historic Preservation stated there was not sufficient information to concur with that assessment, and each alternative, including No-Build, would need to be evaluated. Historic Preservation would decide on the least impactful design once the alternatives have been thoroughly vetted. The impacts of design or construction costs to the project, or timeline requirements for grant funding, are not considered in the Historic Preservation evaluation.
After additional discussion with CDOT, the options to proceed were:
1. Work with CDOT staff on an alternatives analysis. This would evaluate multiple single-span bridge designs, a 15-36-15 three-cell box culvert, and other alternatives identified by Historic Preservation to determine the design that is the "least harm" to the historic resource.
2. Keep the three-cell design and remove the federal money by switching out with a state funded project. No state projects were identified that would be eligible for a funding swap; additionally, the requirements for each grant program would need to be met for the swapped projects.
3. Keep the three-cell design and fully fund the project without the grant; the federal requirements would no longer apply to the project.
Staff consulted with TDG on the alternatives with respect to the financial impacts as well as impacts to project schedule early in 2024.
Option 1 had a high impact both to the schedule and costs of the project. Following the timelines provided by CDOT, the Advertisement for Construction would likely be delayed from November 2024 to early 2027 to achieve Historic Preservation approval, final plan review, and right of way acquisition. The grant has already received a one-year extension, a multiple-year extension would be required. From a cost perspective, the design alternatives analysis is estimated at $120,000 or more to perform and the selected structure will raise the construction costs by $500,000 or more. Cost increases are based on higher structure costs assuming a single span bridge option is ultimately identified. This option would require a new permanent utility easement for a waterline relocation and would increase the roadway profile, resulting in a larger construction footprint. Additional measures to protect historic trees or mitigate unanticipated conflicts arising from the required analysis and Historic Preservation may force additional cost increases. Until the alternatives analysis identified the limits of property impact and acceptable mitigation measures, the right of way costs and costs to mitigate identified impacts would be unknown but are expected to be significant.
Option 2 requirements are the same Option 1, apart from obtaining FHWA approval. The impacts are also similar, there is not a significant time or cost savings between the two options. Additionally, there is not an identified state funded project to switch with federal funding, or other existing state funding available.
Option 3 would allow the three-cell box culvert to be constructed; the design could be completed within existing contract terms and could be advertised for construction much sooner. There are additional cost savings in removing federal funding requirements; the width of the box culvert could be reduced from 60’ to 36’. The large culvert size was set by the view corridor requirements; a smaller cell can hydraulically convey the design flows and meet Denver Water requirements for maintenance. The reduction in size is a significant savings; not only do the structure costs and quantities drop significantly, but the easements get significantly smaller, the design may be easier to complete, and administration of the project during construction would cost less without having to adhere to federal requirements. Profile changes to the trail and roadway would lessen, utilities would be relocated more easily, and there would be greater clearance to the utilities under the box.
The grant provides $1.2M in funding to Littleton, and requires clearances, documentation, and reporting to receive the funds. CDOT understands the impacts caused by the clearance process and acknowledged the only way forward with federal money was the clearance process.
Staff has considered the impacts to the project schedule, the known and unknown increased costs of proceeding with the grant, and the cost savings that can be realized with locally funding the project.
In consideration of the required resources needed to support the grant, the uncertainty of and increases to project costs for selection, design, and construction of the preferred structure, as well as impacts to project schedule, it was recommended that Littleton forego the federal grant funding. That recommendation was supported by city leadership and staff proceeded as such.
An amendment is needed to the IGA that awarded the grant funds to officially release the grant funding.
Since the decision to relinquish the grant, the city has been able to utilize a smaller box culvert, and implement a standard design which is simpler and creates a smaller area of disturbance to the canal, the trees, vegetation, and the residents’ properties, reduce several utility conflicts, all while still accomplishing the intent of the project.
Design, permitting, and licensing are projected to be complete this fall with advertisement in early 2026.
Prior Actions or Discussions
The IGA with CDOT was approved December 7, 2021, with Resolution 54-2021, funding the design and replacement of the Windermere Bridge.
FISCAL IMPACTS:
No work eligible for grant funding has been expended to date. The project will be fully funded by city funds through the 3A Sales Tax Capital Improvement Fund. The cost to proceed with the grant and meet the federal requirements would exceed the value of the grant. The current estimated cost for the project is approximately $2,000,000.
STAFF RECOMMENDATION:
Staff recommends approval of the amendment to the Intergovernmental Agreement.
ALTERNATIVES:
The grant required funds be encumbered by November 2024. Should the IGA amendment not be approved, Littleton would not be eligible for reimbursement of funds from the grant as the funding for the construction phase has not yet been encumbered.
PROPOSED MOTION:
Proposed Motion
I move to approve Resolution 33-2025 approving an amendment to the IGA between the City of Littleton and the Colorado Department of Transportation for reimbursement of costs associated with the South Windermere Street over High Line Canal bridge.