DESIGN CONCEPTS
AT- G R A D E
BOW TIE
•New Washington Street re-aligned to form conventional signalized
intersections with South Street and Hyde Park Avenue, with a wide center
median along New Washington Street. Median width can be increased or
decreased.
•Three through travel lanes provided in each direction on New Washington
Street.
•Eastbound and westbound left turns prohibited on Arborway/New Washington
Street. These maneuvers are accommodated with signalized median U-turns
on each end of the roadway.
•New Washington Street signalized intersection with advanced left turn phase:
• Hyde Park Avenue: for the Northbound and Southbound approach.
• South Street: for the Northbound approach.
•Adequate space available for additional amenities to serve pedestrians,
bicyclists, and transit.
•The location of westerly median U-turn is aligned with Forest Hill Gate at
the Arboretum with minor impact on the existing curb lines. Presents an
opportunity to enhance pedestrian connections.
PROS
Reconnects east-west surface street
Emerald Necklace "missing link"
CONS
EVALUATION
Adds to additional travel distance Analyze the eastern end of the Bow
for east-west left turns
Tie interaction with outlet of Orchard
Hill Rd and Morton Street
Squared off intersections are easy to Multiple lanes for pedestrians to
Evaluate the pros and cons of a
navigate
cross at intersections
median wide enough to be a useful
pedestrian/cyclist/green space versus
the creation of an “empty space”
similar to other landscaped medians
The Bow Tie connections may improve Potential to impact curb lines at
Analyze bus circulation
pedestrian access to the Arboretum to Arboretum gate
the west and to Arborway Yards to the
east
Able to accommodate all movements Increased number of signals on
Evaluate the pedestrian circulation for
within study area. Left turn decision
New Washington Street
navigating the Bow Ties
points are located downstream of the
intersection
The removal of the bridge restores
Evaluate the circulation options
for bicyclists to move through the
sight lines and remove barriers
between neighborhoods and activity
intersections with left turns prohibited
centers
Removal of left turn allows for a wide
and pedestrian friendly median and
additional landscaping
Allows for curb side queuing lane on
New Washington for a taxi/bus lane
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
AT- G R A D E
CONTINUOUS FLOW
•New Washington Street re-aligned to form intersections with South Street
and Hyde Park Avenue, with a center median along New Washington Street.
Median width can be increased or decreased.
•Two through travel lanes provided in each direction for a majority of New
Washington Street. Three travel lanes are provided on New Washington Street
Westbound at South Street.
•The Eeastbound left turn at South Street is not allowed. This maneuver has a
low volume of traffic. Provisions for this maneuver are not provided in the
study area street network and motorists would need to seek alternative routes.
•Adequate space available for additional amenities to serve pedestrians,
bicyclists, and transit.
PROS
Reconnects east-west surface street
Emerald Necklace "missing link"
•New Washington Street signalized intersection with advanced left turn phase:
• South Street: for the Northbound approach. The Westbound left-
turn is accommodated during the same signal phase that permits the New Washington Street through movements.
• Hyde Park Avenue: for the Northbound and Southbound approach. The Eastbound and Westbound left-turns are accommodated during the same
signal phase that permits the New Washington Street through movements.
•Eastbound and westbound left turns allowed on New Washington Street,
except the eastbound left at South Street, by crossing the left-turn traffic to
the opposite side of the roadway and allowing the left turn to be completed
without conflict at the South Street and Hyde Park Avenue intersections. The
left-turn cross-over movement requires additional signalized intersections
to the east of Hyde Park Avenue and between South Street and Hyde Park
Avenue. The four signalized intersections on New Washington Street operate
as a coordinated system with phasing designed to minimize the stop time to
the through movements.
CONS
Prohibition of left turn complicates
access from Arborway eastbound
to South Street north
Reduces the turning restrictions to one Lack of pick-up/drop-off space for
movement
school buses on New Washington
Street and Hyde Park Avenue
Highly efficient intersections move
large volumes of traffic
Allows for many pedestrian to cross
two lanes or less
Bridge removal restores sight lines
and removes barriers between
neighborhoods and activity centers
EVALUATION
The Arborway to South Street left turn
is a low volume move and alternate
routes exist
Applications of this design exists
in NY, NJ, MD and several other
states http://en.wikipedia.org/wiki/
Continuous-flow_intersection
Adds more signals on New
Unfamiliar intersection type may cause
Washington Street and shortens the confusion for all modes
distance between signals
A wide green well-landscape median
Left-turn decision points occur in
has benefits even with no path on
advance of intersections which
will require additional signage,
the median. It enhances the parkway
sign clutter and add confusion to character and provides better tree
motorist
growth, bio-swales for runoff and a
pedestrian area
Complicates bicycle and pedestrian Potential for wide and accessible
access - particularly between the pedestrian median with signalization
Southwest Corridor and the MBTA
Potential for wrong-way entry at Additional right turn lanes may be
left-turn lanes. Left turn lanes result required to eliminate potential for
in vehicles approaching pedestrian wrong-way entrance into left turn
lanes
crossings from unexpected
direction
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
AT- G R A D E
TRADITIONAL INTERSECTION
•New Washington Street re-aligned to form conventional signalized
intersections at South Street and Hyde Park Avenue, with a center median.
•Three through travel lanes are provided in each direction on New Washington
Street.
•Eastbound and westbound left turns are prohibited on New Washington Street.
Provisions for these maneuvers are not provided in the study area street
network and these motorists would need to seek alternate routes.
PROS
Reconnects east-west surface street
Emerald Necklace "missing link"
Traditional intersection signalization
reduces confusion for all modes
Provides area for increased open
space
The removal of the bridge restores
sight lines and remove barriers
between neighborhoods and activity
centers
Left turn restrictions allow for a wide
and pedestrian friendly median and
additional landscaping
Allows for curb side queuing lane on
New Washington for a taxi/bus lane
•New Washington Street signalized intersection with advanced left turn phase:
• Hyde Park Avenue: for the Northbound and Southbound approach.
• South Street: for the Northbound approach.
•New Washington Street center median width can be increased or decreased.
•Adequate space is available for additional amenities to serve pedestrians,
bicyclists, and transit.
CONS
EVALUATION
Prohibition of left turns complicates The left turn prohibition from the
access for vehicles and bicyclists Arborway to South St northbound
from Arborway to Washington
could be tolerated. This is a low
Street, South Street and Hyde Park volume move and alternate routes
Avenue
exist.
Access to Arborway Yard from
Evaluate a mid-block crossing between
Arborway would likely be more
Southwest Corridor Path and Forest
difficult
Hills Station
Lack of a direct connection between Use median space to accommodate
the Southwest Corridor Park and
bicyclists turning movements
the MBTA Station
Multiple lanes for pedestrians to
A wide green well-landscaped median
cross at intersections
has benefits even with no path on the
median and it enhances the parkway
character and provides better tree
growth, bio-swales for runoff and a
pedestrian area
If combined with one bow-tie leg it
would be much more desirable
Left turn restrictions without alternative
accommodations are unacceptable
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
AT- G R A D E
SHEA CIRCLE
DRAFT
SIGNAL CONCEPTS
ROTARY CONCEPTS
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
AT- G R A D E
WASHINGTON STREET/ FOREST HILLS STATION (A)
PROS
CONS
Provides a connection between the end Requires uses of MBTA land and
of the Southwest Corridor park and the reconfiguration of bus bays
Arboretum gate to the Blackwell Path
Extends the bicycle lanes on
Poential impact on MBTA
Washington Street, south of Ukraine
development parcels
Way, northward to meet the sharrows
on South Street
Provides curb-side space for pick-up Increased distance between station
and drop-off of MBTA patrons. This and reconfigured bus bays
space can also be used for school bus
pick-up and drop-off
Expands and moves taxi stand
northward
Reduces conflicts at existing busway at
South Street signalized intersection
Provides capacity for additional buses
at upper level and removes S-curve
to allow for 60-foot articulated buses,
such as the Route 39 bus
EVALUATION
Connections between the SW Corridor
and both the MBTA station and the
Arboretum are important to establish
Left turns for bicyclists in bike lanes
need to be investegated
The area around the north entrance to
the MBTA station can be more strongly
integrated with the openspace network
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
AT- G R A D E
WASHINGTON STREET/ FOREST HILLS STATION (B)
PROS
CONS
Provides a connection between the end Requires uses of MBTA land and
of the Southwest Corridor park and the reconfiguration of bus bays
Arboretum gate to the Blackwell Path
Extends the bicycle lanes on
Potential impact on MBTA
Washington Street, south of Ukraine
development parcels
Way, northward to meet the sharrows
on South Street
Provides curb-side space for pick-up Decking over lower level increases
and drop-off of MBTA patrons. This cost
space can also be used for school bus
pick-up and drop-off
Relocates taxi stand to the north side Increased distance between station
of the station
and reconfigured bus bays
Reduces conflicts at existing busway at Potential negative impact on Route
South Street signalized intersection
39 bus operations
Provides capacity for additional buses Potential negative impact on
at upper level and removes S-curve
Asticou Road with increase in
to allow for 60-foot articulated buses, number of buses accessing station
such as the Route 39 bus
at Washington Street
EVALUATION
Connections between the SW Corridor
and both the MBTA station and the
Arboretum are important to establish
Left turns for bicyclists in bike lanes
need to be investigated
The area around the north entrance to
the MBTA station can be more strongly
integrated with the openspace network
CASEY OVERPASS PROJECT
DESIGN CONCEPTS
BRIDGE
BRIDGE CONCEPT (A)
•New Washington Street re-aligned to form conventional signalized
intersections at South Street and Hyde Park Avenue.
•Left turn lanes are provided in each direction on New Washington Street.
•New Washington Street signalized intersection with advanced left turn phase:
• Hyde Park Avenue: for the Northbound and Southbound approach.
• South Street: for the Northbound approach.
•New Washington Street center median width can be increased or decreased.
A
CROSS-SECTION A
PROS
CONS
Bridge cross-section is reduced to one- Bridge and retaining walls
lane in each direction
disconnect the local neighborhoods
and activity centers
Height of bridge is much shorter
Under bridge environment is less
pedestrian friendly due to lower
bridge
Improved pedestrian and bicycle
Sight lines remain obstructed
accommodations on new bridge
Minimal change to existing regional No improvements to Forest Hills
and local circulation patterns
MBTA Station
Accommodates all movements within
study area
Improves Arborway ramp access at
both New Washington intersections
Reduced roadway cross-section
on New Washington improves
accommodations for pedestrians and
bicycles
EVALUATION
Two narrower bridges would likely
have lower shadow aspects
A high bridge would be good as a
viewing platform, but would require a
longer bridge
Gentle slopes would be better for
bicyclists and pedestrians
The area below the bridge should
feel like part of the neighborhood:
activated, lively and well lit
CASEY OVERPASS PROJECT
M I S S I O N S T A T E M E N T,
P R I N C I P L E S & G OA L S
MISSION STATEMENT
Provide better modal connections, reconnect the historic landscape for the Emerald
Necklace, improve access and circulation for transit, pedestrian and bicycle without creating
unacceptable vehicular traffic congestion/delays.
A COMMON PLATFORM FOR MOBILITY & LIVABILITY GOALS
MOBILITY: the ability to reach a destination and to use, choose and transfer modes within reasonable time and costs.
Mobility is higher when average travel times, variations in travel times, and travel costs are low. The provision of
multi-modal opportunities is essential for good mobility.
LIVABILITY: the use of transportation investments to improve the standard of living, the environment, and quality of
life for all communities. Livable communities are places where transportation, housing and commercial development
investments have been coordinated so that people have access to adequate, affordable and environmentally
sustainable travel options.
GUIDING PRINCIPLES
• Improve safety for all users.
• Address a structurally deficient bridge.
• Protect and respect the design for Arborway Yard.
• Develop alternatives that meet Accelerated Bridge Program budget and
schedule.
• Adopt Principles of Universal Design (accessible and barrier-free design).
• Strive to have an inclusive process for the sharing of information.
• Improve quality of life for residents.
• Integrate artistic elements in designs.
GOALS & MEASURABLE OBJECTIVES (2-3 MEASURES/OBJECTIVE OR 12 - 15 TOTAL)
Goals
Original
Objectives
Measurable
Objectives
Improve roadway geometry to enhance circulation for all
modes and users.
21
5
Improve access, modal and intermodal local and regional
corridor connections to promote transportation choices
14
3
Integrate sustainability into design concepts
11
4
Remove barriers for neighborhood connections and
integrate transit into economic centers and residential
areas
21
3
Create a destination and Sense of Place and celebrate
the area’s architectural, transportation and open space
history
17
2
9
2
93
19
Improve the visibility, connectivity and access to gateway
open spaces
Total
CASEY OVERPASS PROJECT
DESIGN CONTEXT
Commuter Rail Vent Grate
Orange Line Vent Stack
Orange Line Exit Stair
Route 39 Bus Loop
DRAFT
Rotate Orange Line
vent stack
Move stair
northward
Reshape commuter
rail vent grate
Accommodate Route 39
bus loop on street
CASEY OVERPASS PROJECT