NVTA PROJECT UPDATE AMERICAN CANYON SR-29 CORRIDOR IMPROVEMENTS February 3, 2026
Grant Bailey, P.E.
Program Manager - Engineer
2 American Canyon SR 29 Corridor
Purpose of Today’s Update
Status of Environmental Phase of Work
Traffic modeling and existing conditions Critical Milestone: Intersection Safety & Operational Assessment Process (ISOAP) completed December 2025 Informs environmental and engineering studies
Target phase completion - December 2026
Alternatives Evaluation
Initial Findings from Intersection Safety & Operational Assessment Process (ISOAP) Analysis Led to more robust alternative evaluation
Additional Engagement
Presented this information to NVTA Board of Directors on January 21, 2026
3 American Canyon SR 29 Corridor
Project Purpose & Need
Purpose
Improve mobility for all modes
Improve safety
Improve transit travel time & reliability
Support residential and commercial development
Need
Corridor currently lacks:
Multimodal connectivity
Public transit facilities
Low level-of-traffic stress routing options
Intersection constrains lead to extensive queuing & delays Number of collisions on the corridor exceeds state average for similar facilities
4 American Canyon SR 29 Corridor
Project Alternatives
No Build Alternative
Conditions remain as-is
Alternative 1:
Signalization improvements and coordination throughout corridor Business access and transit (BAT) lanes
Transit priority/queue jump
Alternative 2:
Multilane roundabouts at six intersections
American Canyon Rd will remain signalized
Work Common to Both Alternatives:
Construct physically separated Class I shared use path
Lower speed limit from 50 MPH to 35 MPH
Construct 4 bus stops or bus islands
Construct mobility hub
Reconfigure intersections to improve pedestrian crossings
5 American Canyon SR 29 Corridor
Alternative #1 Advantages
Traffic Operations & Intersection Level of Service
Alternative 1 offers improved LOS
Transit Reliability
Business Access and Transit (BAT) Lanes
Queue Jump Lanes
ROW
Limited property acquisitions and driveway impacts
Vehicle Miles Traveled (VMT)
No increase in VMT
Alternative #1 Supports:
Transit reliability
Emergency response times
Limited ROW impacts
Improved mobility for all modes (including bikes/pedestrians)
6 American Canyon SR 29 Corridor
Alternative #2 Advantages
Injury collision reduction potential
Alternative 2 carries higher crash reduction potential
Local/public preference
General sentiment from public workshop was a preference for roundabouts Roundabout carry a public perception of improved traffic flow Alternative #2 Supports
Potentially reduced incidence of collision
Improved mobility for all modes (including bikes/pedestrians)
7 American Canyon SR 29 Corridor
Signalization Improvements
Additional Signals
Crawford Wy
Poco Wy / S Napa Junction
Side Street Improvements
Additional Turning Lanes
New Crosswalks across SR 29
Signal Coordination
Adaptative Signal Coordination
Driven by actual vehicle volumes
Why?
Minimize side street delays and accommodate future land use growth Regulate N-S vehicle throughput
Transit Queue Jumps and Transit Signal Priority at all signalized Intersections Easier and safer pedestrian crossings
8 American Canyon SR 29 Corridor
Business Access & Transit Lanes
Benefits:
Transit
Efficiently and reliably move transit vehicles through the corridor Couple with intersection queue jumps and transit signal priority (TSP) technology Local Access
Acceleration/deceleration lane for commercial & residential facilities along the corridor Improves operations between intersections
Limits impacts to and consolidation of existing driveways Standard Shoulder
Accommodates vehicle breakdowns
Enforcement
Technology driven
Signal-mounted enforcement cameras
Potential for bus-mounted enforcement cameras
9 American Canyon SR 29 Corridor
Intersection Operation Evaluation Results
Intersection Level of Service (LOS)
Alternative 1 - Signals
Alternative 2 - Roundabouts
Level of Service
Existing Conditions 2025 AM (PM)
Opening Year 2030 AM (PM)
Design Year 2050 AM (PM)
Opening Year 2030 AM (PM)
Design Year 2050 AM (PM)
During Peak Period
Crawford Way
B(F)
C (B)
B (B)
B (C)
C (E)
Donaldson Way
C(C)
C (C)
C (D)
F (E)
F (F)
Poco Way/S Napa Junction Rd
E(D)
A (D)
A (F)
F (C)
F (E)
Rio Del Mar
C(B)
C (D)
E (D)
F (D)
F (F)
Eucalyptus Dr
B(B)
A (C)
E (E)
F (E)
F (F)
Napa Junction Rd
D(E)
D (C)
D (D)
F (E)
F (F)
LOS Key
Average Delay(seconds/vehicle)
Signalized
Unsignalized
Acceptable LOS
A-B-C
Acceptable
0-25
0-25
D
At Capacity
35-55
25-35
Unacceptable LOS
E
Poor
55-80
35-50
F
Failure
>80
>50
10 American Canyon SR 29 Corridor
Alternative Evaluation
11 American Canyon SR 29 Corridor
Cost, Right of Way & Delivery
Costs
Alt 1: ~$58M (ROW & Construction)
Alt 2: ~$75M (ROW & Construction)
ROW
Alt 1: minimal impacts to public right of way and private property corners Alt 2: major acquisitions, potential structure demolitions Alternative 2 Delivery Risk
Limited use of three-lane roundabouts in California
No examples in the proposed configuration of multiple consecutive roundabouts Potential VMT mitigation could increase costs
12 American Canyon SR 29 Corridor
Alternative Evaluation Results
Evaluation Criteria
Contributing Factors
Alternative 1
Alternative 2
Purpose and Need
Alternative accomplishes points outlined in the purpose and need of the project. 1 1
Traffic
Better Intersection Level of Service
During Peak Period
1 0
Transit
Better improves transit operations
1 0
Bike and Ped
Better improves Pedestrian and Bike Connectivity
0 0
VMT
No VMT Increase
1 0
Safety
CMF Qualitative Analysis
0 1
Cost
Lower Total Project Cost
1 0
Environmental
Less environmental impacts
0 0
Department of Transportation Concerns
Caltrans has less concerns related to nonstandard design 1 0
Local Preference
Alternative preferred by users and local residents
0 1
City Preference
Alternative preferred by City Council & Staff
TBD
TBD
Local Impacts
Less Temporary construction impacts
0 0
Less Right of Way impacts
1 0
Less Significant Driveway Impacts
1 0
TOTAL
8 3
13 American Canyon SR 29 Corridor
Next Steps
Staff recommendation
Carry forward Alternative #1 for environmental clearance Do not carry Alternative #2 forward
Benefits
Accelerates phase completion to the end of 2026
Limits use of additional resources to further evaluate Alternative #2
Q&A – Thank you!
15 American Canyon SR 29 Corridor
LOS Table with No Build Conditions
Expanded Intersection Level of Service (LOS)
No Build Alternative
Alternative 1 - Signals
Alternative 2 - Roundabouts
Level of Service
Existing Conditions 2025 AM (PM)
Opening Year 2030 AM (PM)
Design Year 2050 AM (PM)
Opening Year 2030 AM (PM)
Design Year 2050 AM (PM)
Opening Year 2030 AM (PM)
Design Year 2050 AM (PM)
During Peak Period
Crawford Way
B(F)
F(F)
F(E)
C (B)
B (B)
B (C)
C (E)
Donaldson Way
C(C)
D(C)
F(D)
C (C)
C (D)
F (E)
F (F)
Poco Way/S Napa Junction Rd
E(D)
F(E)
F(F)
A (D)
A (F)
F (C)
F (E)
Rio Del Mar
C(B)
D(C)
F(F)
C (D)
E (D)
F (D)
F (F)
Eucalyptus Dr
B(B)
B(B)
F(F)
A (C)
E (E)
F (E)
F (F)
Napa Junction Rd
D(E)
D(F)
F(F)
D (C)
D (D)
F (E)
F (F)
LOS Key
Average Delay(seconds/vehicle)
Signalized
Unsignalized
Acceptable LOS
A-B-C
Acceptable
0-25
0-25
D
At Capacity
35-55
25-35
Unacceptable LOS
E
Poor
55-80
35-50
F
Failure
>80
>50
16 American Canyon SR 29 Corridor
Solano Napa Area Base Model (SNABM) Sub-Area Mode
(Focus on Project Study Area)
Traffic Modeling Methodology
Regional Model Covers All Counties.
Focused on Solano and Napa Counties
Project specific Sub-Area to capture major changes in land use and traffic circulation.
Model also includes the City of American Canyon General Plan changes and growth projections. i.e. Watson Ranch Development
Developed regional and local volumes.