Traffic Impact Assessment
for
Mixed-Use Commercial & Residential Development
Located at the Corner of Humboldt and Jefferson Streets by
ams associates, inc.
801 Ygnacio Valley Road, Suite 220
Walnut Creek, CA 94596
(925) 943-2777
ams Project No. 2514-1
Prepared:
February 2, 2025
Prepared By:
Farhad Iranitalab, R.C.E. 33142, R.T.E. 1695
26 INTRODUCTION
ams associates, Inc. has prepared this memorandum to assess the impact of the proposed mixed-use commercial and residential development at the corner of Humboldt and Jefferson Streets in the Town of Yountville.
This memorandum will evaluate the existing traffic issues and the impact of the proposed development.
Project Setting
The project is located on the northeast corner of the intersection of Washington and Humboldt streets to the east of Jefferson Street on 0.26-acres vacant parcels. The project is designated for Residential Scaled Commercial Land Use as shown in Figure 1.
Project Description
proposed project will develop the existing parcels with a two-story mixed-use development comprised of 2,307 square feet of special retail and two residential units on the first floor and three residential units on the second floor. The retail portion of the project is considered as specialty retail and residential units are two bedrooms and two baths with a private entrance and shared outdoor deck and BBQ area with outdoor fireplace. The retail would operate between ten AM and six PM Monday through Friday, and 11 AM to 6 on Saturday and Sunday. The project is consistent with the General Plan land use designation.
Site Access as
Access to the Site is provided from the twenty-four feet wide driveway on Humboldt Street approximately seventy-five feet to the east of Washington Street as shown in Figure 2.
Existing Roadway Network
Figure 3 presents the existing Town of Yountville circulation network. Washington Street is designated major street in the Town General Plan, Circulation Element, and Jefferson and Humboldt Streets are both designated local streets.
Project Trip Generation
Trip generation represents the amount of traffic generated by a development. The Institute of Transportation Engineers (ITE), Trip Generation Manual, is the industry standards to calculate the number of trips generated by a Land Use category. The trip generation manual, 11th Edition, dated September 2021 is the latest edition. Table 1 presents the summary of trip generation.
Table 1- Proposed Site Trip Generation
Based on the size of the proposed mixed-use development (five residential units, and small specialty retail store with limited store hours there would not be a high trip generated by the proposed project. As shown in Table 1 the project would generate 144 daily trips, two trips during AM and ten trips during the PM peak hours.
Conclusion
Based on our evaluation of proposed project generated trips we do not anticipate any significant impact on traffic flow and operation. However, the project would eliminate one or maximum of two parking spaces on Humboldt Street for constructing the access driveway onto the site.
CEQA Transportation Analysis (VMT)
The State of California Governor’s Office of Planning and Research (OPR) issued proposed updates to the CEQA guidelines in November 2017 and an accompanying technical advisory guidance finalized in December 2018 (OPR Technical Advisory) that amends the Appendix G question for transportation impacts to delete reference to vehicle delay and level of service and instead refer to Section 15064.3, subdivision (b)(1) of the CEQA Guidelines asking if the project will result in a substantial increase in vehicle miles traveled (VMT).
Based on the OPR screening criteria any commercial development project less than 50,000 square feet is considered local serving development and is presumed to have less than significant impact.
ITE Land Use Unit Daily
2-way
AM Peak Hour PM Peak Hour
Enter Exit Total Enter Exit Total
826 Specialty Retail
(ITE 9th Edition Manual)
1,000 sq. ft.
GFA
44.32 62% 38% 6.84 48% 52% 2.71
220- Multi-Family Low
Rise
Dwelling
units 6.74 24% 76% 0.4 63% 37% 0.51
Project Trips
826 Specialty Retail
2,500 sq. ft.
GFA
110 NA NA NA 3 4 7
220- Multi-Family Low
Rise 5 34 0 2 2 2 1 3
Total project Trips 144 0 2 2 5 5 10