Construction Traffic Analysis

Transcription

1 Construction Traffic Analysis

2 TRANSMITTED Ms. Julie Berger Senior Project Manager Impact Sciences, Inc. 234 East Colorado Boulevard, Suite 205 Pasadena, California RE: Figueroa & Adams Residential Project Construction Traffic Analysis Dear Julie, A traffic impact analysis has been conducted to assess potential traffic impacts of the Figueroa & Adams Residential Project during that project s construction period. This analysis is consistent with the traffic impact analysis which was prepared in July 2008 by our firm and was approved by LADOT, and which addressed the project traffic impacts following the completion of construction and long-term occupancy. The procedures, data and results of the construction traffic analysis are detailed below. Construction Phases Project construction activities are estimated to occur over a 24 months period, now estimated to begin in May 2010 and end in May 2012 (Note: Traffic Impact Study dated July 2008 assumed completion in 2011). The 24-month period construction activities will be sequenced through three phases as shown in Table 1. It should be noted that some overlaps might occur between phases. Table 1 Project Construction Phases Phase Approximate Time Period Start Month End Month 1. Grading/ Excavation 6 month May 2010 November Framing/ Superstructure 12 month November 2010 November Finishes/ Landscaping 6 month November 2011 May 2012 Please note that the above schedule is tentative and adjustments in the schedule may occur due to unforeseen circumstances.

3 Ms. Julie Berger Page 2 During the construction period, the delivery trucks would access/egress the project site during nonpeak hours. Construction workers will park at an off-site lot and be shuttled to the project site until the garage portion of the project is completed, at which time they will park in the garage. However, to reflect the maximum construction traffic generation at the site and on the surrounding streets, it is assumed that the construction workers will park on-site during the entire construction period. Likewise, it is expected that on-site construction activity will fluctuate on a weekly basis, depending largely on the number of workers and construction trucks needed for the activities during each time period. In order to remain conservative, the portion of the project construction phase which generates the highest daily construction-related traffic was analyzed. Thus, the values below represent the maximum rather than average conditions during each phase. The maximum number of construction workers on-site and delivery trucks entering/leaving the site per day will vary according to the construction phase. These maximum values are estimated in Table 2 below. Table 2 Project Construction Phases Phase Workers/Day No. of Excavation/Delivery Trucks/Day 1. Grading/ Excavation 15 workers 40 trucks 2. Framing/ Superstructure 140 workers 20 trucks 3. Finishes/ Landscaping 125 workers 5 trucks Construction Trip Generation The daily, AM and PM peak hour trip rates used for determining the project s construction trip generating potential are based on the 7th Edition of ITE Trip Generation manual for General Light Industrial workers. The rates are shown in Table 3. Table 3 Project Trip Generation Rates and Equations General Light Industrial (per employee) LU 110 Daily: T = 3.02 (E) AM Peak Hour: T = 0.44 (E); I/B = 83%, O/B = 17% PM Peak Hour: T = 0.42 (E); I/B = 21%, O/B = 79% Where: T = trip ends E = employee I/B = inbound O/B = outbound Source: Trip Generation, 7th Edition, Institute of Transportation Engineers, Washington D.C., 2003.

4 Ms. Julie Berger Page 3 Using all of the above rates, a construction-related trip generation for the proposed project was calculated and is illustrated in Table 4 below. Truck trips were added to these trips to estimate total site trips for each phase. Because excavation/delivery truck trips will occur during nonpeak hours due to restrictions placed on the haul route permit, they are not included in the trip generation rate. Table 4 Construction-Related Trip Generation AM Peak Hour * PM Peak Hour * Construction Stages Maximum Workers/Trucks Daily In Out Total In Out Total Worker Trips 1. Grading/ Excavation 15 workers/day Less Transit/Walk-in/Bicycle **: 15% (7) (1) 0 (1) 0 (1) (1) Framing/ Superstructure 140 workers/day Less Transit/Walk-in/Bicycle **: 15% (63) (8) (2) (9) (2) (7) (9) Finishes/ Landscaping 125 workers/day Less Transit/Walk-in/Bicycle **: 15% (57) (7) (1) (8) (2) (6) (8) Truck Trips 1. Grading/ Excavation 40 trucks/day 160 *** Framing/ Superstructure 20 trucks/day 80 *** Finishes/ Landscaping 5 trucks/day 20 *** Total Daily Construction Trips 1. Grading/ Excavation Framing/ Superstructure Finishes/ Landscaping * Since all truck-devlivery activities occur during non-peak hours, no truck trips were caluculated during AM and PM peak periods. ** Transit/Walk-in/Bicycle trip credits for the construction employee trips were taken to be the same percentage as the proposed project. This trip adjustment factor was approved for this site by LADOT and was discussed in the Traffic Impact Study dated July *** One inbound and one outbound trip per day and a Passenger Car Equivalent Factor of 2.0 included for each truck. As illustrated in Table 4 above, the maximum number of construction period vehicles accessing/egressing the site is expected to occur during Phase 2. For the purpose of a

5 Ms. Julie Berger Page 4 conservative study, the proceeding analysis assumes the Phase 2 trip generation (440 daily trips with 53 AM Peak Hour trips and 50 PM Peak Hour trips) will occur during the entire 24-month construction period. The proposed project s operational trip generation identified in the July 2008 Traffic Impact Report was based on a conservative analysis that assumed all units would be leased by the general public. Based on this tenancy, it was estimated that there would be 870 daily trips with 64 AM Peak Hour trips and 82 Peak Hour trips. With implementation of mitigation requiring that the project occupancy be 90% students, faculty and staff of local education institutions, trip generation would be reduced by 50% and no significant traffic impact would occur at any of the study intersections. As shown in the analysis below, no significant traffic impact is anticipated to occur during the construction phase; therefore, no mitigation is required.. Intersection Construction Traffic Impacts of the Proposed Project Because the project s construction trip generation is less than the operational trip generation (approximately 50% fewer daily trips with 17% fewer AM Peak Hour Trips and 39% fewer PM Peak Hour trips), construction activity is anticipated result in less traffic impact at any study intersections than the completed proposed project. Even so, the temporary construction-related traffic impacts at the 11 study intersections identified in the July 2008 Traffic Impact Report were analyzed using the same existing traffic count volumes, cumulative traffic growth assumptions and utilizing the same methodology used in the Traffic Impact Report (namely the procedures outlined in Circular Number 212 of the Transportation Research Board 1 ). Since construction workers are expected to live throughout the Los Angeles region, they are also expected to arrive to the project site from all directions. As such, the construction trip distribution is assumed to be the same as the operational project trip distribution. Based on the CMA methodology, the project s construction impacts on the future conditions were calculated conservatively utilizing the same methodology which was used for the completed project in the Traffic Impact Report dated July Those results are summarized in Table 5. 1 Interim Materials on Highway Capacity, Circular Number 212, Transportation Research Board, Washington, D.C., 1980

6 Ms. Julie Berger Page 5 Table 5 Critical Movement Analysis (CMA) Summary Existing (2008) and Future (2011) Without and With Project Construction Trips Future (2011) Without Future (2011) With Peak Existing Project Construction Project Construction No. Intersection Hour CMA LOS CMA LOS CMA LOS Impact 1. Figueroa Street and AM D F F Washington Boulevard PM C E E th Street and AM A A A US- 10 W/B Ramps PM A A A Hoover Street and AM B C C US- 10 E/B Ramps PM B C C rd Street and AM A B B US- 110 S/B Off-ramp PM A A A rd Street and AM A B B Figueroa Street PM B D D rd Street and AM A A A Flower Street PM B D D Adams Boulevard and AM C D D Hoover Street PM D E E Adams Boulevard and AM C E E Figueroa Street PM D F F Adams Boulevard and AM A B B Flower Street PM D E E Adams Boulevard and AM E F F US- 110 N/B Off-ramp PM B C C Figueroa Street and AM A B B Jefferson Boulevard PM B C C As shown above, based upon a CMA analysis, the project construction-related traffic will not cause a significant traffic impact at any study intersections; therefore; no mitigation is required. Parking During Construction During the construction period, the existing 125 church parking spaces on the project site will be displaced. The developer has entered into an agreement with St. Vincent School, which is located immediate north of the project site, to utilize the school s parking lot for interim church parking on Sundays, when church attendance is highest. The letter of agreement is included in Appendix A. A separate lot will also be leased off-site for construction workers needing parking prior to completion of the site parking garage. Therefore, no significant parking impacts are anticipated during the construction period and no mitigation is required.

7 Ms. Julie Berger Page 6 Mitigation The construction of the project is not anticipated to cause significant traffic impacts at any of the study intersections. In addition, interim parking for the church has been arranged to address the displacement of that parking and off-site parking will be provided for construction workers prior to completion of the site parking garage. As a result, no mitigation measures are warranted. If you have any questions, please feel free to contact me with any questions. Sincerely, George Rhyner Senior Transportation Engineer GR:kl C19372 JA89145 enclosures

8 APPENDIX A Letter of Interim Parking agreement

9

10