Attachment 19 - Applicant's Traffic Consultant LetterOctober 10, 2016
Mr. Doug Rich
Valley Oak Partners, LLC
734 The Alameda
San Jose, CA 95126
Subject: Response to Comments on the TIA Prepared for the Proposed Winchester
Office Project in Los Gatos, CA.
Dear Mr. Rich;
We understand that the Town has received a comment from a nearby resident Mr. Andrew Spyker
about the trip generation rate used in our traffic study for the Winchester office project. The TIA,
titled Winchester Boulevard Office Development TIA, prepared by Hexagon Transportation
Consultants, Inc., dated September 13, 2016, used counted trip generation rates of comparable
office buildings in Los Gatos to estimate the proposed project trip generation, instead of using ITE
trip generation rates. This letter provides our response to Mr. Spyker’s comments.
Reason for Using Counted Trip Generation Rates
According to the Town of Los Gatos Traffic Impact Policy, in addition to using trip generation rates
from the latest ITE Trip Generation Manual, SanDAG, Caltrans, or City of San Jose, “a Town-
sponsored or peer-reviewed traffic study may also be used to determine trip generation rates.”
Based on Hexagon’s recent experience in preparing TIAs in the Town of Los Gatos, the Planning
Commission and members of the public have voiced concerns that the ITE trip generation rates
do not reflect local conditions in Los Gatos. Therefore, to address this concern, Hexagon used
counted trip generation rates conducted at three comparable office buildings. The counted rates
were checked against the ITE trip generation rates for a general office building, and were found to
be slightly lower in the AM peak hour and slightly higher in the PM peak hour, but consistent with
the ITE trip generation rates (see Table 1). Using the ITE trip generation rates would be
conservative in estimating trip generation in the AM peak hour, whereas using counted trip
generation rates would be conservative in estimating trip generation in the PM peak hour. Based
on expressed public concerns of using rates that reflect local conditions, Hexagon used the
counted trip generation rates instead of the ITE trip generation rates. Hexagon’s TIA report, which
documented the trip generation data collection and comparison of counted and ITE trip generation
rates, was peer-reviewed by the Town’s traffic consultant.
Counted Trip Generation Data Collection Process
As discussed above, Hexagon was able to find three office buildings in Los Gatos that were
comparable to the proposed office building and could be counted. Selection criteria included the
size of the building, tenant types, and location (dedicated parking supply not shared with other
uses) . Trip generation counts were conducted by recording vehicle volume in and out of the
driveways of office buildings on a typical weekday in March 2016. The resulting data were
averaged to derive the counted trip generation rates (see Table 1).
ATTACHMENT 19
Mr. Doug Rich
October 10, 2017
Page 2 of 3
Table 1
Counted Trip Generation Rates
Analysis Using ITE Trip Generation Rates
Using the counted trip generation rates, the TIA concluded that the proposed project would not
generate any significant intersection impacts. Since there is expressed public concern that the
counted trip generation rates are not conservative, Hexagon evaluated the project impacts using
the ITE trip generation rates. As shown on Table 2, using the ITE average trip generation rates for
an office building, the proposed project would generate a net 45 trips (41 in and 4 out) during the
AM peak hour and 42 trips (6 in and 36 out) during the PM peak hour. Compared to the trip
generation estimated using counted trip generation rates, the ITE trip generation rates would yield
7 more project trips during the AM peak hour and 4 fewer project trips during the PM peak hour.
As shown on Table 3, using the ITE trip generation rates to analyze the project’s potential
impacts, the resulting levels of service under project conditions showed that the project would not
generate any significant intersection impacts.
Compared to the level of service results analyzed using the counted trip generation rates, the
levels of service did not change, and the average delays under project conditions increased or
decreased by only 0.1 seconds when analyzed using the ITE trip generation rates. Therefore, the
traffic impact findings are consistent using either the counted trip generation rates or the ITE trip
generation rates.
If you have any questions please do not hesitate to call.
Sincerely,
HEXAGON TRANSPORTATION CONSULTANTS, INC.
Gary K. Black
President
Surveyed Sites 1 Size Unit Trips In
Trips
Out
Total
Trips
Peak
Rate Trips In
Trips
Out
Total
Trips
Peak
Rate
475 Alberto Way 3 30.22 ksf 37 3 40 4 37 41
16795 Lark Avenue 22.40 ksf 19 12 31 4 33 37
975 University Avenue 15.00 ksf 16 2 18 0 32 32
Total 67.62 ksf 72 17 89 8 102 110
1.32 1.63
1.56 1.49
Notes:
1. Trip generation surveys were conducted in March 2016.
3. The size reported for 475 Alberto Way reflects the occupied square footage at the time of the counts.
AM Peak Hour PM Peak Hour
Average Surveyed Rates
Average ITE Rates 2
2. Average ITE trip rates for general office building based on ITE's Trip Generation, 9th Edition for land use code 710.
Mr. Doug Rich
October 10, 2017
Page 3 of 3
Table 2
Project Trip Generation Estimates Using ITE Rates
Table 3
Intersection Levels of Service Summary – Analyzed Using ITE Rates
Land Use Size Unit Rate Trips Rate In Out Total Rate In Out Total
Proposed Project
Office1 30.07 ksf 11.03 332 1.56 41 6 47 1.49 8 37 45
Existing Land Use
Single Family Homes 2 3 d.u.9.52 29 0.75 0 2 2 1 2 1 3
Net Project Trips 303 41 4 45 6 36 42
2. Single-Family Detached Housing (Land Use 210) peak hour average rates based on ITE's Trip Generation, 9th Edition.
Daily AM Peak Hour PM Peak Hour
Notes:
2. General Office Building (Land Use 710) peak hour average rates based on ITE's Trip Generation, 9th Edition.
Incr.Incr.
Avg.Avg.In Crit.Incr.Avg.Avg.In Crit.Incr.Avg.
Peak Count Delay Delay Delay In Crit.Delay Delay Delay In Crit.Delay
#Intersection Hour Date (sec)LOS (sec)LOS (sec)V/C (sec)LOS (sec)LOS (sec)V/C (sec)LOS
1 Winchester Blvd. and Lark Ave.AM 03/08/16 21.2 C 21.2 C 0.1 0.001 21.9 C 21.9 C 0.1 0.002 22.3 C
PM 03/08/16 18.7 B 18.8 B 0.1 0.002 20.7 C 20.8 C 0.2 0.001 21.5 C
2 University Ave. and Lark Ave.AM 03/08/16 21.9 C 23.2 C 12.4 0.071 22.0 C 22.2 C 0.0 0.001 23.0 C
PM 03/08/16 25.7 C 25.7 C 0.1 0.002 27.2 C 27.3 C 0.1 0.002 29.0 C
3 SR17 Southbound Ramps and Lark Ave.AM 03/08/16 27.4 C 27.4 C 0.0 0.000 28.9 C 28.9 C 0.0 0.001 31.9 C
PM 03/08/16 33.4 C 33.5 C 0.1 0.004 38.3 D 38.6 D 0.3 0.003 46.7 D
4 SR17 Norththbound Ramps and Lark Ave.AM 03/08/16 18.1 B 18.1 B 0.1 0.001 18.7 B 18.8 B 0.1 0.001 21.6 C
PM 03/08/16 12.9 B 13.0 B 0.2 0.003 13.6 B 13.7 B 0.0 0.000 15.2 B
5 Winchester Blvd. and Daves Ave.AM 03/08/16 30.8 C 30.9 C 0.2 0.009 30.7 C 30.8 C 0.2 0.009 31.1 C
PM 03/08/16 26.1 C 26.1 C 0.1 0.003 27.3 C 27.4 C 0.2 0.004 30.0 C
6 Winchester Blvd. and Shelburne Ave. 1 AM 03/08/16 0.7
(10.9)
A
(B)
0.8
(11.4)
A
(B)--0.7
(11.3)
A
(B)
0.8
(11.9)
A
(B)--0.7 (12.7)A (B)
PM 03/08/16 0.6
(12)
A
(B)
0.7
(13.7)
A
(B)--0.5 (13)A
(B)
0.7
(15.3)
A
(C)--0.7 (17.2)A (C)
7 University Ave. and Shelburne Ave. 1 AM 03/08/16 1.5
(12.1)
A
(B)
1.6
(12.3)
A
(B)--1.5
(12.1)
A
(B)
1.6
(12.3)
A
(B)--1.5 (13)A (B)
PM 03/08/16 1.3
(13)
A
(B)
1.6
(13.6)
A
(B)--1.3
(13.1)
A
(B)
1.6
(13.7)
A
(B)--1.5 (14.6)A (B)
8 N. Santa Cruz Avenue and Blossom Hill Rd.AM 03/08/16 25.0 C 25.1 C 0.1 0.004 26.0 C 26.1 C 0.2 0.004 28.4 C
PM 03/08/16 23.0 C 23.1 C 0.1 0.003 23.5 C 25.0 C -10.0 0.006 28.1 C
9 University Ave and Blossom Hill Rd.AM 03/08/16 21.4 C 21.6 C 0.3 0.006 21.4 C 21.6 C 0.3 0.006 21.7 C
PM 03/08/16 30.0 C 30.0 C 0.0 0.003 30.0 C 30.1 C 0.0 0.003 30.3 C
10 N. Santa Cruz Ave and Los Gatos-Saratoga Rd.*AM 03/02/16 41.5 D 41.5 D 0.0 0.000 42.0 D 42.1 D 0.1 0.002 44.2 D
PM 03/02/16 48.3 D 48.3 D 0.0 0.000 48.6 D 48.6 D 0.0 0.000 50.3 D
11 University Ave. and Los Gatos-Saratoga Rd.*AM 03/02/16 33.7 C 33.7 C -0.1 0.001 33.7 C 33.7 C 0.0 0.001 34.2 C
PM 03/02/16 39.7 D 39.8 D 0.2 0.003 39.7 D 39.8 D 0.1 0.003 39.8 D
Notes:
* Denotes CMP intersection
1. For unsignalized intersections, intersection-wide average delay and corresponding LOS are first reported, and worst-approach delay and corresponding LOS are reported in
parentheses.
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