HomeMy WebLinkAboutEX10_RS_Trip_Generation_Assessment_220920_v1WSADA ADDITION RENTION
TRIP GENERATION ASSESSMENT
City of Renton, WA
Prepared for: Vicki Giles Fabre
Washington State Auto Dealers Association
621 SW Grady Way
Renton, WA 98057
September 2022
09/20/2022
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
HEATH HEATH & & ASSOCIATES, ASSOCIATES, INCINC TTrransportation ansportation PlanniPlanning ng and and EngineeringEngineering
September 20, 2022
Vicki Giles Fabre
Washington State Auto Dealers Association
621 SW Grady Way
Renton, WA 98057
The intent of this assessment is to provide the city of Renton with a site characteristic description,
trip generation summary and on-site parking supply substantiation for the proposed development
herein referred to as WSADA Addition Renton. A project description is given below.
PROJECT DESCRIPTION
The WSADA (Washington State Auto Dealers Association) Addition Renton project proposes to
construct a two-story addition to their existing facility at 621 SW Grady Way in the city of Renton.
The addition, located at the northwestern corner of the building, is to comprise approximately
1,390 square feet and is to consist of an elevator, stairs, bathrooms and storage area. The subject
site, situated on the southeast corner of SW Grady Way & Raymond Avenue SW, comprises a
cumulative 1.07-acres within tax parcel #’s: 334040-4730 & -4805. Access is to continue by way of
one driveway extending south from SW Grady Way, one driveway extending north from SW 12th
Street and via the alley that bisects the subject site between Raymond Avenue SW and Seneca
Avenue SW. Figure 1 below shows the aerial vicinity. The southerly parcel functions as an
overflow parking lot for specialty events. Approximately 43 parking stalls are provided within the
northerly parcel with an additional 32 parking stalls provided in the southerly overflow parking lot
(75 total on-site stalls). A conceptual site plan is presented in Figure 2 on the following page.
Figure 1: Aerial Vicinity
SITE LOCATION
HEATH HEATH & & ASSOCIATES, ASSOCIATES, INCINC TTrransportation ansportation PlanniPlanning ng and and EngineeringEngineering
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
2/10
NFIGURE 2HEATH & ASSOCIATESTRAFFIC PLANNING AND ENGINEERINGSITE PLANWSADA ADDITION RENTONWSADA Addition Renton Trip Generation & Parking AssessmentPO Box 397 Puyallup, WA 98371 (253) 770 1401 heathtraffic.comHeath & Associates 3/10
TRIP GENERATION
Trip generation is used to determine the magnitude of project impacts on the surrounding street
system. This is usually denoted by the quantity or specific number of new trips that enter and exit
a project during a designated time period, such as a specific peak hour (AM or PM) or an entire
day. As previously stated, the addition is to entail the construction of bathrooms, an elevator,
stairs and storage space. It should be noted that the new space is anticipated solely to augment
existing operations. As such, no new trips are anticipated as a result of the addition.
However, to present a conservative analysis, data presented in this report was taken from the
Institute of Transportation Engineer's publication Trip Generation, 11th Edition. The existing
WSADA building on-site comprises 9,008 square feet. The 1,390 square foot addition will yield a
total building square footage 10,398 square feet. As the total gross floor area post-improvement
will be greater than 10,000 square feet, the land use defined for the improvement is proposed as
General Office Building (LUC 710). Square footage was utilized as the input variable with ITE
average rates to determine trip ends. Volumes for the average weekday daily trips (AWDT), AM
peak hour and PM peak hour trips are summarized in Table 1 below.
Table 1: Project Trip Generation
Land Use Size AWDT AM Peak-Hour Trips PM Peak-Hour Trips
In Out Total In Out Total
General Office
Building (LUC 710) 1,390 SF 15 2 0 2 0 2 2
Based on ITE data, the project can be expected to generate 15 average daily trips with 2 new trips
occurring in the AM peak hour (2 inbound / 0 outbound) and 2 new trips in the PM peak hour (0
inbound / 2 outbound). However, it should again be noted that the addition is not anticipated to
generate any new trips as the space is intended solely to augment existing operations.
DISTRIBUTION & ASSIGNMENT
Trip distribution describes the process by which project generated trips are dispersed on the
roadway network surrounding the site. Estimated PM peak hour trip distribution to and from the
subject site is illustrated in Figure 3 on the following page. All project-generated traffic was
assigned to the existing SW Grady Way project driveway to present a conservative analysis.
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
4/10
WSADA Addition Renton Trip Generation & Parking AssessmentPO Box 397 Puyallup, WA 98371 (253) 770 1401 heathtraffic.comHeath & Associates 5/10
PARKING DEMAND
The existing WSADA building within tax parcel #: 334040-4730 contains 43 parking stalls, meeting
the day-to-day parking demands of WSADA. As stated in the previous Traffic Analysis for WSADA
Auxiliary Parking Lot (May 21, 2018), WSADA occasionally requires additional parking associated
with the training of dealership personnel. Said training occurs several times a week from 10 AM to
3 PM, intentionally provided outside AM and PM peak hours to accommodate the trainees. The
overflow parking lot comprising an additional 32 stalls accommodates overflow parking needs
during training events.
As previously noted, the proposed building addition is intended to improve the utility of the
WSADA facility by offering bathrooms, an elevator, stairs and extra storage area. No increase to
employees or services is anticipated, nor is a change in day-to-day activity is expected. The
addition would provide a better environment for personnel on-site. As such, no increased parking
demand is anticipated as a result of the addition, and existing parking provisions on-site are
deemed adequate.
SUMMARY
WSADA Addition Renton proposes for the construction of a ~1,390 square foot, two-story addition
to an existing facility located in the city of Renton. The existing 9,008 square foot building is
situated within 0.75-acre tax parcel #: 334040-4730, which comprises 43 parking spaces. The 43
stalls associated with the existing building provide adequate parking for the day-to-day parking
needs of WSADA. An additional 32 parking stalls serve the facility within a southerly parcel, #:
3340404805 (0.32-acres). This parking lot is intended to accommodate site parking demand
overflow, anticipated to occur during staff training events. Access to the site is provided by way of
one driveway extending south from SW Grady Way, the alley bisecting the site between Raymond
Avenue SW and Seneca Avenue SW, and via one driveway extending north from SW 12th Street
into the auxiliary southerly parking lot.
Based on ITE data, the project can be expected to generate 15 new average daily trips with 2 new
trips occurring in the AM peak hour (2 inbound / 0 outbound) and 2 new trips in the PM peak hour
(0 inbound / 2 outbound). However, the nature of the addition, which entails an elevator, stairs,
bathrooms and a storage room, is not anticipated to produce a change in day-to-day operations.
No tangible increase to parking demands on-site is anticipated, and as such the existing parking
provisions on-site are deemed adequate. The proposed ~1,390 square foot addition does not
substantiate the need for additional parking.
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
6/10
It should be noted that the City of Renton Fee Schedule (2021-2022) exacts Transportation Impact
Fees (TIF) for general office uses at $14.58 per square foot. As such, the following TIF calculation
is made for the proposed addition:
1,390 sq. ft. x $14.58/sq. ft. = $20,266.20
Based on the development proposal, a TIF of $20,226.20 of may be required on behalf of the
WSADA Addition Renton. However, final fees and calculations will be determined by the City.
Please feel free to contact me should you require further information.
Aaron Van Aken, P.E. PTOE
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
7/10
10/4/21, 2:09 PM https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=AWDVTE&x=&edition=639&locationCode=General …
https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=AWDVTE&x=&edition=639&locationCode=General Urban/Suburban&co…1/1
General Office Building
(710)
Vehicle Trip Ends vs:1000 Sq. Ft. GFA
On a:Weekday
Setting/Location:General Urban/Suburban
Number of Studies:59
Avg. 1000 Sq. Ft. GFA:163
Directional Distribution:50% entering, 50% exiting
Vehicle Trip Generation per 1000 Sq. Ft. GFA
Average Rate Range of Rates Standard Deviation
10.84 3.27 - 27.56 4.76
Data Plot and Equation
T = Trip EndsX = 1000 Sq. Ft. GFA
Study Site Average RateFitted Curve
Fitted Curve Equation: Ln(T) = 0.87 Ln(X) + 3.05 R²= 0.78
Trip Gen Manual,11th Edition Institute of Transportation Engineers
0 200 400 6000
1,000
2,000
3,000
4,000
5,000
6,000
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
8/10
10/4/21, 2:10 PM https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=TASIDE&x=&edition=639&locationCode=General Ur…
https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=TASIDE&x=&edition=639&locationCode=General Urban/Suburban&cou…1/1
General Office Building
(710)
Vehicle Trip Ends vs:1000 Sq. Ft. GFA
On a:Weekday,
Peak Hour of Adjacent Street Traffic,
One Hour Between 7 and 9 a.m.
Setting/Location:General Urban/Suburban
Number of Studies:221
Avg. 1000 Sq. Ft. GFA:201
Directional Distribution:88% entering, 12% exiting
Vehicle Trip Generation per 1000 Sq. Ft. GFA
Average Rate Range of Rates Standard Deviation
1.52 0.32 - 4.93 0.58
Data Plot and Equation
T = Trip EndsX = 1000 Sq. Ft. GFA
Study Site Average RateFitted Curve
Fitted Curve Equation: Ln(T) = 0.86 Ln(X) + 1.16 R²= 0.78
Trip Gen Manual,11th Edition Institute of Transportation Engineers
0 200 400 600 800 1,0000
500
1,000
1,500
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
9/10
10/4/21, 2:10 PM https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=TPSIDE&x=&edition=639&locationCode=General U…
https://itetripgen.org/PrintGraph.htm?code=710&ivlabel=QFQAF&timeperiod=TPSIDE&x=&edition=639&locationCode=General Urban/Suburban&cou…1/1
General Office Building
(710)
Vehicle Trip Ends vs:1000 Sq. Ft. GFA
On a:Weekday,
Peak Hour of Adjacent Street Traffic,
One Hour Between 4 and 6 p.m.
Setting/Location:General Urban/Suburban
Number of Studies:232
Avg. 1000 Sq. Ft. GFA:199
Directional Distribution:17% entering, 83% exiting
Vehicle Trip Generation per 1000 Sq. Ft. GFA
Average Rate Range of Rates Standard Deviation
1.44 0.26 - 6.20 0.60
Data Plot and Equation
T = Trip EndsX = 1000 Sq. Ft. GFA
Study Site Average RateFitted Curve
Fitted Curve Equation: Ln(T) = 0.83 Ln(X) + 1.29 R²= 0.77
Trip Gen Manual,11th Edition Institute of Transportation Engineers
0 200 400 600 800 1,0000
200
400
600
800
1,000
1,200
1,400
WSADA Addition Renton
Trip Generation & Parking Assessment
PO Box 397 Puyallup, WA 98371
(253) 770 1401 heathtraffic.com
Heath & Associates
10/10