Southwest Arterial Southwest Arterial DMATS Presentation Project - PDF document

Southwest Arterial Southwest Arterial DMATS Presentation Project Status Update Robert Schiesl Assistant City Engineer PURPOSE OF MEETING � Review current project status � Inform you of the results and recommendations of the preliminary design VE evaluations � Inform you of the proposed design modifications � Project schedule � Project schedule � Receive your input and comments 1

Southwest Arterial Project PROJECT PARTNERSHIP The #1 Surface Transportation Priority in the Dubuque Area For: � Dubuque City Council � Dubuque County Board of Supervisors � Dubuque Metropolitan Area Transportation Study (DMATS) � Greater Dubuque Development Corporation � Dubuque Area Chamber of Commerce Continuing to move forward with the development of the Southwest Arterial Southwest Arterial Project Project Development • Connects U.S. Hwy 20 with U.S. Hwy 61/151 • 4-lane Divided Freeway (6.1 Miles) • Priority 1 Access Control • Three Interchanges � Hwy 20, Hwy 61/151, N. Cascade Road H 20 H 61/151 N C d R d • Full Build Cost Estimate $125 Million 2

Southwest Arterial Project Corridor Alignment Map Southwest Arterial Project Where Are We Today? � NEPA Clearance - Completed 2004 � Preliminary Engineering Design - Completed 2008 � Preliminary Engineering Design Completed 2008 • Final Engineering Design � Underway • Right-of-Way Property Acquisition � Underway • Archaeological & Cultural Resource Mitigation � Underway • Construction � Under Contract - N. Cascade Reconstruction 3

Southwest Arterial Project Value Engineering (VE) Study Preliminary Design Evaluation & Recommendations • Value Engineering Study - Completed December, 2009 g g y p , � Identify potential modifications that might decrease construction cost � Increase the value of the project • Preliminary VE design evaluation - Completed November, 2010 • 10 - Initial VE Alternatives were evaluated � 7 - VE Concepts Recommended For Further Consideration � Potential total estimated VE savings: $7,500,000 � 3 - VE Concepts Not Recommended • Most significant VE recommendations are the proposed modifications to the SW Arterial / U.S. 20 / Seippel Road interchange area. Potential savings $6,200,000 Original US 20 Interchange Cross Over Cross Over Bridge 4

US 20 Interchange - Concept A Evaluated Not Recommended • Folded diamond with loop ramps • Eliminate Cross Over Bridge over US20 Bridge over US20 • Wetland Impacts • Exit Loop Ramp Speed Deceleration Bottom of Hill Safety Concern • Entry Loop Ramp Slow Entry Speed Slow Entry Speed Merging Traffic Safety Concern US 20 Interchange - Concept A Evaluated Not Recommended • Folded diamond with loop ramps • Eliminate Cross Over Bridge over US20 Bridge over US20 • Wetland Impacts • Exit Loop Ramp Speed Deceleration Bottom of Hill Safety Concern • Entry Loop Ramp Slow Entry Speed Slow Entry Speed Merging Traffic Safety Concern 5

US 20 Interchange - Concept A Evaluated Not Recommended • Folded diamond with loop ramps • Eliminate Cross Over Bridge over US20 Bridge over US20 • Wetland Impacts • Exit Loop Ramp Speed Deceleration Bottom of Hill Safety Concern • Entry Loop Ramp Slow Entry Speed Slow Entry Speed Merging Traffic Safety Concern US 20 Interchange - Concept A Evaluated Not Recommended • Folded diamond with loop ramps • Eliminate Cross Over Bridge over US20 Bridge over US20 • Wetland Impacts • Exit Loop Ramp Speed Deceleration Bottom of Hill Safety Concern • Entry Loop Ramp Slow Entry Speed Slow Entry Speed Merging Traffic Safety Concern 6

US 20 Interchange - Concept C Evaluated Not Recommended • Mixed configuration: Standard diamond with a folder diamond / loop ramp • Eliminate Cross Over • Eliminate Cross Over Bridge over US20 • Avoids Environmental Impacts • Entry Loop Ramp Lower Entry Speed Merging Traffic Safety Concern US 20 Interchange - Concept C Evaluated Not Recommended • Mixed configuration: Standard diamond with a folder diamond / loop ramp • Eliminate Cross Over • Eliminate Cross Over Bridge over US20 • Avoids Environmental Impacts • Entry Loop Ramp Lower Entry Speed Merging Traffic Safety Concern 7

US 20 Interchange - Concept B Recommended Original US 20 Interchange Cross Over Cross Over Bridge 8

Design US 20 Interchange - Concept B Revisions Recommended • Change to standard “diamond interchange” configuration • Simple, safe interchange • Eliminate loop ramps • Eliminate crossover bridge over US 20 • US20 Entry Ramps Higher entry speeds Improve Merge Traffic • US20 Exit Ramps Less Deceleration • Use roundabout intersections • Reduce environmental and property impacts • Reduce project cost by approx. $6.2 million Design US 20 Interchange - Concept B Revisions Recommended • Change to standard “diamond interchange” configuration • Simple, safe interchange • Eliminate loop ramps • Eliminate crossover bridge over US 20 • US20 Entry Ramps Higher entry speeds Improve Merge Traffic • US20 Exit Ramps Less Deceleration • Use roundabout intersections • Reduce environmental and property impacts • Reduce project cost by approx. $6.2 million 9

Design US 20 Interchange - Concept B Revisions Recommended • Change to standard “diamond interchange” configuration • Simple, safe interchange • Eliminate loop ramps • Eliminate crossover bridge over US 20 • US20 Entry Ramps Higher entry speeds Improve merge traffic • US20 Exit Ramps Less deceleration Improved safety • Use roundabout intersections • Reduce environmental and property impacts • Reduce project cost by approx. $6.2 million Design US 20 Interchange - Concept B Revisions Recommended • Change to standard “diamond interchange” configuration • Simple, safe interchange • Eliminate loop ramps • Eliminate crossover bridge over US 20 • US20 Entry Ramps Higher entry speeds Improve merge traffic • US20 Exit Ramps Less deceleration Improved safety • Use roundabout intersections • Reduce environmental and property impacts • Reduce project cost by approx. $6.2 million 10

N. Cascade Road / English Mill Design Interchange Layout Revisions • Diamond interchange • Use roundabout intersections • Eliminate loop ramp Eliminate loop ramp • Reduce property impacts by approx. 9 acres • Reduce project cost by approx. $240,000 • VE Alternative Eliminate interchange Eliminate interchange No at-grade intersections Priority 1 access control N. Cascade Road / English Mill Design Interchange Layout Revisions • Diamond interchange • Use roundabout intersections • Eliminate loop ramp Eliminate loop ramp • Reduce property impacts by approx. 9 acres • Reduce project cost by approx. $240,000 • VE Alternative Eliminate interchange Eliminate interchange No at-grade intersections Priority 1 access control 11

N. Cascade Road / English Mill Design Interchange Layout Revisions • Diamond interchange • Use roundabout intersections • Eliminate loop ramp Eliminate loop ramp • Reduce property impacts by approx. 9 acres • Reduce project cost by approx. $240,000 • VE Alternative Eliminate interchange Eliminate interchange No at-grade intersections Priority 1 access control N. Cascade Road / English Mill Design Interchange Layout Revisions • Diamond interchange • Use roundabout intersections • Eliminate loop ramp Eliminate loop ramp • Reduce property impacts by approx. 9 acres • Reduce project cost by approx. $240,000 • VE Alternative Eliminate interchange Eliminate interchange No at-grade intersections Priority 1 access control 12

N. Cascade Road / English Mill Design Interchange Layout Revisions • Diamond interchange • Use roundabout intersections • Eliminate loop ramp Eliminate loop ramp • Reduce property impacts by approx. 9 acres • Reduce project cost by approx. $240,000 • VE Alternative Eliminate interchange Eliminate interchange No at-grade intersections Priority 1 access control Military Road Area Revisions • Eliminate retaining walls • Provide landscaped cut slopes on both sides of Southwest Arterial • Requires additional property acquisition Original Tiered Wall Concept • Reduce project cost by approx. $2 Million • Added bike / pedestrian trail between Military Road and US 151 / 61 • VE Alternative Construct tunnel Cost prohibitive Landscaped Slopes Recommended 13

Design Revisions • Folded diamond with loop ramps • Use roundabout intersections • Eliminate 2 bridges on ramps, switch to box culvert • Added bike / pedestrian trail through interchange to Old Davenport Road • Reduce project cost by approx. $400,000 US 151 / 61 Interchange Layout Design Revisions • Folded diamond with loop ramps • Use roundabout intersections • Eliminate 2 bridges on ramps, switch to box culvert • Added bike / pedestrian trail through interchange to Old Davenport Road • Reduce project cost by approx. $400,000 US 151 / 61 Interchange Layout 14