Military Bases

The Puget Sound region is home to a number of military bases that house and employee thousands of enlisted staff and civilian workers. Daysim does not account for trips to and from these locations so they are handled with a separate submodel. This processing occurs within scripts/supplemental/generation.py

Enlisted personnel are placed on military parcels according to current distributions and do not grow into future, concurrent with military plans of steady staffing into the future. These military-specific parcels are appended to the original land-use file, providing a new set of households and workers for Daysim, thereby allowing travel to and from military zones.

JBLM

Joint Base Lewis McChord is one of the largest employers in the region. Travel in and out of the installation is constrained to 17 gates spread throughout the installation where more than 153,000 daily vehicle trips occur everyday. In SeaCast, trips to and from JBLM are matched to base year observations by gate. This is accomplished by treating each gate as a separate traffic analysis zone and scaling the total trips at each gate to the observed gate volumes. There are 11 distinct gates with major traffic volumes and those gates are:

Total Daily Gate Volumes

Gate	Daily Vehicle Volume
Camp Murray	4,000
Lewis North	34,000
McChord Family Housing	3,000
McChord Main Gate	15,000
McChord South Gate	6,200
Liberty Gate	33,000
Logistics Center	5,000
Madigan Gate	23,000
DuPont Gate	13,000
East Gate	14,500
Mounts Road	2,000

Trips are broken down by work and non-work related trip purposes using existing staffing levels. Work trips are then distributed to fixed locations based on license plate and zip code surveys while non-work related trips rely on a gravity model distribution. The total trips by purpose in the base year are:

• Total Workers Commuting from Off Base: 41,700
• Total Daily Work Trips to JBLM: 83,400 (each worker gets 2 work trips)
• Total Daily Non-Work Trips: 69,700

As noted above, work trips for each gate are distributed to TAZ's around the region using the results of a JBLM zip code survey and Bluetooth observations of flow from a 2013 survey performed for the Washington State Department of Transportation. The distribution of these trips remains constant into the future. These distributions vary for each gate and are shown below.

Camp Murray (TAZ 3061)

Sub Area	Inbound	Outbound
I-5 Thurston County	57%	57%
DuPont	11%	11%
Steilacoom / University Place	10%	10%
Lakewood	5%	5%
Tacoma	6%	6%
King County	0%	0%
Puyallup	6%	6%
East Pierce County	3%	3%
Kitsap Peninsula	2%	2%
Lewis Main	0%	0%
Lewis North	0%	0%

Lewis North (TAZ 3070)

Sub Area	Inbound	Outbound
I-5 Thurston County	24%	26%
DuPont	3%	3%
Steilacoom / University Place	2%	2%
Lakewood	9%	7%
Tacoma	8%	10%
King County	1%	2%
Puyallup	11%	11%
East Pierce County	10%	6%
Kitsap Peninsula	1%	2%
Lewis Main	31%	31%
Lewis North	0%	0%

McChord Gates (TAZ's 3346, 3348, 3350)

Sub Area	I1nbound	Outbound
I-5 Thurston County	20%	17%
DuPont	2%	1%
Steilacoom / University Place	0%	0%
Lakewood	36%	34%
Tacoma	23%	23%
King County	2%	2%
Puyallup	10%	14%
East Pierce County	3%	3%
Kitsap Peninsula	2%	3%
Lewis Main	2%	3%
Lewis North	0%	0%

Liberty Gate (TAZ 3351)

Sub Area	I1nbound	Outbound
I-5 Thurston County	32%	37%
DuPont	6%	4%
Steilacoom / Universit3y Place	1%	2%
Lakewood	14%	11%
Tacoma	13%	15%
King County	2%	2%
Puyallup	8%	7%
East Pierce County	2%	3%
Kitsap Peninsula	1%	1%
Lewis Main	0%	0%
Lewis North	21%	18%

Madigan & Logistics Gate (TAZ's 3352 & 3353)

Sub Area	I1nbound	Outbound
I-5 Thurston County	35%	36%
DuPont	9%	5%
Steilacoom / University Place	1%	0%
Lakewood	20%	17%
Tacoma	19%	26%
King County	2%	2%
Puyallup	9%	9%
East Pierce County	2%	2%
Kitsap Peninsula	1%	1%
Lewis Main	0%	0%
Lewis North	2%	2%

DuPont Gate (TAZ 3354)

Sub Area	I1nbound	Outbound
I-5 Thurston County	57%	57%
DuPont	11%	11%
Steilacoom / University Place	10%	10%
Lakewood	5%	5%
Tacoma	6%	6%
King County	0%	0%
Puyallup	6%	6%
East Pierce County	3%	3%
Kitsap Peninsula	2%	2%
Lewis Main	0%	0%
Lewis North	0%	0%

East Gate (TAZ 3355)

Sub Area	I1nbound	Outbound
I-5 Thurston County	0%	0%
DuPont	0%	0%
Steilacoom / University Place	0%	0%
Lakewood	0%	0%
Tacoma	0%	0%
King County	0%	0%
Puyallup	3%	3%
East Pierce County	97%	97%
Kitsap Peninsula	0%	0%
Lewis Main	0%	0%
Lewis North	0%	0%

Mounts Road Gate (TAZ 3356)

Sub Area	I1nbound	Outbound
I-5 Thurston County	100%	100%
DuPont	0%	0%
Steilacoom / University Place	0%	0%
Lakewood	0%	0%
Tacoma	0%	0%
King County	0%	0%
Puyallup	0%	0%
East Pierce County	0%	0%
Kitsap Peninsula	0%	0%
Lewis Main	0%	0%
Lewis North	0%	0%

These improvements to JBLM have led to noticeable improvements in traffic flow in and around JBLM in Pierce County.