Appendix D Traffic Impact Analysis - westplainseis.com

7. CUMMULATIVE ANALYSIS
7.1.1 2032 Pipeline Conditions
The Year 2032 Base Volumes were calculated based on the 2019 volumes with pipeline projects and
growth projected by the SRTC regional travel demand models. A comparison was made between the
2008 model and the 2032 “without Spokane Tribe Land Use” model. The projected background annual
growth between 2008 and 2032 was determined to be 1.52%. Using this rate, the 2019 volumes (which
accounted for all projects currently approved and in the “pipeline” for construction) were projected 13
years ahead as the 2032 base volumes, as shown in Figure 20. The operations in the 2032 forecast year
across the existing network are provided in Table 21. This table illustrates that the current network will
be deficient at several intersections based on projected growth rates and approved projects.
Table 21. Level of Service for 2032 Pipeline PM Peak Hour Conditions
INTERSECTION
Peak hour Level of Service (LOS)
(S) Signalized Critical
(U) Unsignalized Movement By
(R) Roundabout Approach Delay LOS
Hwy. 2 / Craig Rd. U SB LTR * F
Hwy. 2 / Lundstrom St. U NB LTR 109.6 F
Hwy. 2 / Lawson St. S -- 29.9 C
Hwy. 2 / Garfield St. S -- 58.7 E
Hwy. 2 / Hayford Rd. S -- 150.3 F
Craig Rd. / Deno Rd. U EB LTR 9.5 A
Craig Rd. / McFarlane St. U WB LTR 11.8 B
Craig Rd. / Thorpe Rd. East U SB LR 9.3 A
Craig Rd. / Thorpe Rd. West U NB LR 9.3 A
Craig Rd. / SR 902 U SB LTR 155.4 F
Hwy. 2 / Fairchild AFB S -- 40.4 D
Craig Rd. / 6 th Ave. U WB Lt 18.1 C
Hwy 2 / Driveway West U SB Rt 26.1 D
* Excessive Delay
7.1.2 2032 With Project (Alternatives 1, 2 & 3)
From this platform of the calculated 2032 base volumes, each of the alternative buildout volumes were
added and the network evaluated to determine the project’s impact on the LOS of the intersections. 2032
With Project volumes are shown in Figures 21 - 23. The intersections with levels of service dropping
below ‘D’ were mitigated to bring them into compliance with the appropriate agency requirements. For
WSDOT facilities (Hwy.2, SR 902), sufficient mitigation was required to bring the intersection back to
the LOS projected under 2032 base conditions (see table 21).
As shown in Table 22, the addition of the proposed development under Alternative 1 brings all Hwy 2
study intersections to failing levels of service, based on the network and intersection layout. Further
failures are projected on Craig Road north and south of Hwy.2. Based on the mitigation table as shown
in Table 23, by adding or enhancing signals and/or roundabouts at affected intersections and modifying
the lane usage at unsignalized intersections, the operations are improved within compliant ranges. Note
that the LOS at Hwy.2/Craig and Hwy.2/Hayford, though still at LOS F, are improved over the 2032
base conditions shown in Table 21. Detailed descriptions of the suggested mitigations for all alternatives
are included at the end of this section.
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Traffic Impact Analysis April 28, 2011