Consider Visual Quality Design Options for Armstrong Boulevard Interchange

The purpose of this case is to review general policy direction to assist the Anoka County Highway Department, through SRF Consulting Group, complete final design of the Armstrong Interchange as it relates to the final aesthetics and finishes of the improvement project design. Please note, the attached figures are for comparison purposes only. The intent of this case is to provide general direction so more detailed final design can be completed. As staff balances aesthetics with cost implications, staff did not want to lose the opportunity to add design elements that may be of importance to the City Council. It is perfectly acceptable to choose the base design (no additional cost to the City) if that is the policy direction of the City Council.

Generally speaking, Staff is seeking direction on the level of desired aesthetic treatment of bridge wall sections, retaining walls, fencing/railings, landscaping, and street and pathway lighting. These design choices will have an impact on the City's cost contribution to this important improvement project, which will serve as a gateway to the COR and will likely set a precedent for the design of future interchanges throughout this section of the highway 10 corridor. Staff has been attempting to balance the design of this gateway improvement with realistic cost assumptions and as such asked SRF to prepare three aesthetic design options for City review purposes. Specific details of each option are contained within the attached presentation.

1. Option 1 (or Level 1) is the base design for which all costs would be covered by Anoka County.
2. Option 2 (or Level 2) is a 'mid-level' design option with partial aesthetic enhancements. The base design costs as noted above would be covered by Anoka County, but the increased cost differential would be the responsibility of the City.
3. Option 3 (or Level 3) is the 'high-level' design option with the greatest amount of aesthetic enhancements throughout the project. The funding split would be the same as Option 2 above but the City's total contribution would increase significantly with the added aesthetics.

This item was discussed very briefly during the last Council work session.  At that time, Council did provide general direction to staff to work with SRF to develop a design containing aesthetic enhancements that fell somewhere between the base design option (Level 1) and the mid-level design option (Level 2). However, since this direction was provided, SRF has indicated that they require some more specific direction on several items.  Staff is therefore requesting additional Council direction this evening through consensus on the following items.
 
Bridges

1. Does Council support brick pilasters above the decking and at bridge corners using a thin brick veneer?  This item impacts the structural design of the bridge.  Staff does not recommend this option as there is evidence that the brick veneer could cause maintenance issues in the future.
2. Does Council support ornamental steel “picket” style railing (6" picket spacing) vs. chain link fencing?  Staff recommends supporting this option due to the significant aesthetic benefits versus the relatively low cost increase over chain link fencing.

 Retaining Walls

1. Does Council support brick pilasters using a form-liner with multi-color finish?  Staff recommends that Council allow Staff to explore this option during final design.
2. Does Council support ornamental steel “picket” style railing (6" picket spacing) vs. chain link fencing on Wall G?  As with the bridge, staff recommends supporting this option due to the positive benefit-cost ratio.

 Streetscape

1. Does Council support providing underground conduit to center medians with green areas to accommodate irrigation for future landscaping?  Staff recommends supporting the installation of underground conduit to allow for future irrigation of green/landscaped median areas due to the low cost to install conduit with the project.
2. Does Council desire intersection lighting only vs. continuous lighting along Armstrong Boulevard?  Staff recommends that Council allow Staff to explore the use of continuous lighting during final design, as well as estimating costs to install underground conduit in the boulevards to allow for future lighting along the corridor if continuous lighting is not supported at this time.

 
Again, Staff is very cognizant of the cost implications of these choices and the current funding approvals and funding requests. With that in mind, Staff will respond to questions raised by SRF during final design per Council’s previous direction to work with SRF to develop a design containing aesthetic enhancements that fall somewhere between the base design option (Level 1) and the mid-level design option (Level 2).  The City will still have additional opportunities to influence detailed, final design at future key dates, provided that the design choices do not impact structural design components.

Anoka County tentatively plans to submit final plans to the Minnesota Department of Transportation (MnDOT) by March 28, 2014, meaning many of these visual design choices need to be made in the coming weeks.

15 minutes.

Potential funding sources include Tax Increment Financing District No. 2 (rail station construction contingency surplus) or Tax Increment Financing District No. 14 (an internal loan for an interim period of time would be required as there is not currently increment available in TIF District No. 14).

Development Services Manager
City Engineer

The desired outcome of this case is to obtain Council direction on those items listed herein to allow SRF to continue working towards final design completion for the Armstrong Interchange. There are still some unknowns in the design and funding that prevent detailed design review from being a productive discussion at this time.