Portland-Milwaukie Light Rail Project - FEIS - Volume 1 - TriMet

SE 8 th Avenue/SE Powell Boulevard – 2030 No-Build Alternative, LPA to Park Avenue, and
MOS to Lake Road
During the PM peak hour, the free-flow movement from SE 8 th Avenue is currently heavy and
continues to be heavy in 2030. Relatively free-flow conditions in the westbound direction on SE
Powell Boulevard allow for the SE Woodward Street eastbound to SE 8 th Avenue southbound
movement to be free flow to access SE Powell Boulevard. This does not allow for gaps in the
traffic flow for southbound stop-controlled traffic on SE 8 th Avenue at SE Woodward Street to
discharge at an adequate rate, and consequently queuing on SE 8 th Avenue becomes problematic
(as previously described). During the AM peak hour, the merge area on SE Powell Boulevard
(westbound) creates congestion due to heavy traffic flow that has queuing spillback to the
intersection of SE 8 th Avenue/SE Woodward Street, but the southbound queue on SE 8 th Avenue
is not problematic. The merge area cannot be relocated due to the constraints of the Ross Island
Bridge and therefore represents an existing non-project-related problem that has impacts to
surrounding study area intersections.
SE 12 th Avenue/SE Division Street (due to closing SE Clinton between SE 11 th and SE 12 th )
With the light rail alignment, SE Clinton Street will be closed between SE 11 th and SE 12 th
Avenues. Vehicles that currently travel through this portion of SE Clinton Street eastbound will
be directed to a new traffic signal at SE Milwaukie Avenue/SE Gideon Street, and westbound
vehicles on SE Clinton Street will be directed to existing traffic signals at SE 12 th Avenue/SE
Division Street and SE 11 th Avenue/SE Division Street. Without an improvement at SE 12 th
Avenue/SE Division Street, larger trucks would need to continue to travel north through the
neighborhood (out of direction) on SE 12 th to SE Madison Avenue before turning westbound.
In order to allow westbound trucks to be redirected to SE Division Street, the project has
identified mitigation at SE 12 th Avenue/SE Division Street. This intersection would be modified
to allow trucks to turn northbound to westbound, providing adequate turning radii for WB 67
trucks (with 53-foot trailers). This improvement should minimize freight access impacts for the
CEID.
SE 11 th /SE 12 th /SE Milwaukie Avenues from SE Division Street to SE Powell Boulevard
There is a need to develop and coordinate appropriate mitigation strategies with ODOT and the
City of Portland that address the vehicle operations at SE 11 th Avenue/SE Division Street with
the project and other traffic-related concerns in this segment of roadways. Mitigation strategies
should address the following concerns:
Potential southbound queuing along SE Milwaukie Avenue from SE Powell Boulevard to
eliminate potential for queue to extend to, and over, the light rail and heavy rail tracks
Identify and analyze potential diversion for vehicles to surrounding roadway network due
to delay and develop strategies (if necessary) to address diversion
Additional delay at SE 11 th Avenue/SE Division Street intersection due to light rail
crossings of SE 11 th Avenue
The work that is needed to develop these mitigation strategies will be determined through
coordination and detailed analysis within the scope of extended Preliminary Engineering.
Portland-Milwaukie Light Rail Project FEIS 4-37
Chapter 4. Transportation