Appendix D Traffic Impact Analysis - westplainseis.com

MITIGATION-ALT 2, CONTINUED
2012 PM Peak
BG + Alt2-
INTERSECTION
Buildout
2032 PM Peak
BG + Alt2-
Buildout
Hwy. 2 /
--
LOS = E
Fairchild AFB Delay = 75.8
Optimized Signal Timing, Add NB Lt turn
bay and WB through lane
Craig Rd. /
6th Ave.
Add NB Right turn bay --
--
--
LOS = D
Delay = 50.6
CM = WB Lt
LOS = E
Delay = 42.6
CM = WB Lt
LOS = D
Delay = 28.5
Hwy. 2 / CM = SBL CM = SBL
Dwy. Middle LOS = F LOS = F
Signalized
Roundabout
Delay = * Delay = *
LOS = C
LOS = D
Delay = 31.1 Delay = 46.8
LOS = A
LOS = E
Delay = 9.8 Delay = 65.8
Listed below are improvements recommended for consideration to reduce traffic impacts associated with
the subject project. The project’s recommended proportional share contribution to each mitigation is also
listed. The proportional share for off-site intersections is calculated by divided the project generated
traffic volume by the total intersection volume for each respective scenario.
2012 (Alt. 2 Buildout) Mitigations:
Hwy 2 / Craig: Install traffic signal and widen the NB and SB approaches to provide and
exclusive left turn lane. Alternatively, consider installation of a roundabout.
Project Proportional Share: 34.2%
Resulting LOS & Delay (sec): C/31.6 / A/7.8
Hwy 2 / Hayford: Optimize signal timing and convert the inside SB thru lane to a 2 nd SB left
turn lane.
Project Proportional Share: 15.8%
Resulting LOS & Delay (sec): D/45.9
Craig / SR 902: Install traffic signal or consider installation of a roundabout.
Project Proportional Share: 23.7%
Resulting LOS & Delay (sec): B/15.6 / A/8.6 (roundabout)
Hwy 2 / Middle Driveway: Install traffic signal and approach improvements (SB Middle
Driveway); install a WB right turn lane. Alternatively, consider installation of a roundabout.
Project Proportional Share: 100%
Resulting LOS & Delay (sec): C/31.1 / A/9.8 (roundabout)
West Plains Development – Spokane Tribe Page | 70
Traffic Impact Analysis April 28, 2011