Item 7 - Southlake-Carroll-Progress-Mtg-2015-03-06-w-SH114-ramp-reversalN. Carroll Avenue
Access Evaluation
March 6, 2015
Study Purpose
•Identify any operational deficiencies
related to access along N. Carroll
Avenue between SH 114 and FM 1709
•Develop alternatives to improve access
to N. Carroll Avenue
•Lake Wood Acres
•South View
•Foxborough
Data Collection
•Recent traffic studies
•Reviewed 2030 Mobility Master Plan
•In-field observations during AM and PM
peak periods
•Turning movement counts
•SH 114 interchange
•Lakewood Drive
•NB left-turn into 7-Eleven property
Existing
Traffic
Counts
•SH 114
Interchange
•N. Carroll Ave. at
Lakewood Drive
AM [PM]
Existing Traffic Counts
•N. Carroll Ave. at
FM 1709
AM [PM]
]
Field Observations
Lakewood Drive
•PM rush hour is critical peak
•Existing median configuration
for SB left-turn creates
numerous conflict points and
potential safety problems
•Existing raised island design
on retail drive is not effective
•No significant delays along EB
and WB approaches during
peak periods (queue 1-2 vehs)
•Vehicle gaps are created from
upstream traffic signals at SH
114 and Federal Way
N.
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Lakewood Drive
Traffic Analysis
Lakewood Drive
•Acceptable LOS
during the AM
peak
•EB approach is
LOS F during
the PM peak
•However, avg.
queue is only 1
vehicle long
Movement
AM Peak PM Peak
Delay
(sec/veh )LOS Delay
(sec/veh )LOS
NB Left 9.6 A 11.3 B
SB Left 9.6 A 9.9 A
EB Approach 31.8 D 60.8 F
WB Approach 11.3 B 11.4 B
Access Alternatives
Wild Wood Lane
•Option A (C2U-60’)
•Aligns with existing
drainage channel
between 800 and 850
Wild Wood Lane
•Includes TxDOT
deceleration lane
•ROW acquisition
($252,000)
•Construction Cost
($853,000)
•Engineering/Survey
($85,000)
•Total Project Cost
($1,190,000)
Access Alternatives
Wild Wood Lane
•Option B (C2U-60’)
•Includes TxDOT
deceleration lane
•ROW acquisition
($210,000)
•Construction Cost
($696,000)
•Engineering/Survey
($69,600)
•Total Project Cost
($975,600)
Access Alternatives
Wild Wood Lane
•Option C (C2U-60’)
•Aligns with existing driveway along SH 114
•Does not meet TxDOT spacing requirements from existing off-ramp
•Includes TxDOT deceleration lane
•ROW acquisition ($168,000)
•Construction Cost ($609,500)
•Engineering/Survey ($61,000)
•Total Project Cost ($838,500)
Access Alternatives
•Option D (C2U-60’)
•Includes TxDOT
deceleration lane
•ROW acquisition
($132,000)
•Construction Cost
($534,500)
•Engineering/Survey
($53,500)
•Total Project Cost
($720,000)
Wild Wood Lane
Access Alternatives
Lakewood Drive
(Option 1)
•Extend median for SB left-
turn lane
•Add access drive along
Lakewood Drive
•Stripe EB approach as a
two-lane approach (11’
lanes)
•No significant change in
LOS for EB approach
•Reduces conflict points
•Eliminates confusion
•Improves safety
•Total Project Cost ($30,000)
Access Alternatives
•Option 1 plus…
•Relocate existing
driveway along N.
Carroll
•Modify existing raised
island and driveway
radius along east
approach
•Total Project Cost
($85,000)
Lakewood Drive
(Option 2)
Access Alternatives
•Option 1 plus…
•Relocate existing
driveway along N.
Carroll
•Install median island to
restrict left-turn from
side streets
•Total Project Cost
($85,000)
Lakewood Drive
(Option 3)
Traffic Analysis –Lakewood Drive
Option 2
•Revised traffic for
proposed
modifications and
the future retail
development traffic
•Delay increases
for EB and WB
approaches
•EB Queue = 2 veh
•WB Queue = 1 veh
Movement
AM Peak PM Peak
Delay
(sec/veh )LOS Delay
(sec/veh )LOS
NB Left 10.3 B 12.7 B
SB Left 9.7 A 10.3 B
EB Left/Thru 52.7 F 179.1 F
EB Right 11.4 B 13.1 B
WB Approach 11.6 B 11.6 B
Traffic Analysis –Lakewood Drive
Option 3
•No left-turns from
side streets
•Minimal delay
along side streets
•Previous left-turns
from Lakewood
Drive are required
to make U-turn
south of
intersection
Movement
AM Peak PM Peak
Delay
(sec/veh )LOS Delay
(sec/veh )LOS
NB Left 10.5 B 12.9 B
SB Left 10.4 B 10.3 B
EB Left/Thru --------
EB Right 11.7 B 13.4 B
WB Approach 11.6 B 11.6 B
Lakewood Acres
•Conclusions/Recommendations
•No significant congestion problem at N.
Carroll Avenue & Lakewood Drive
•Vehicle gaps are created from upstream
traffic signals at SH 114 and Federal Way
•Do not implement access connections from
Wild Wood Lane
•Option 2 results in fewer restrictions for
Lakewood Drive approach
•Consider implementing Option 3 if side street
delay increases along Lakewood Drive
Field Observations
Foxborough Neighborhood
•No significant delays observed along Foxborough Lane or
Owenby Lane
•Foxborough Lane traffic can easily turn right out of
neighborhood and make a U-turn at Byron Nelson Parkway
Access Alternatives
Foxborough
Neighborhood
•Extension of Cross
Lane
•ROW acquisition
($504,000)
•Construction Cost
($1,051,000)
•Engineering/Survey
($105,000)
•Total Project Cost
($1,660,000)
•Connection not needed to support
current conditions
•Consider implementing when
vacant tract develops
Field Observations
South View Neighborhood
•No significant delays along
Southcrest Court and
Owenby Lane
•Vehicle gaps are created
from upstream traffic signals
at FM 1709 and Federal
Way
•No recommended access
improvements
FM 1709 at N. Carroll Avenue
SB Right-Turn Lane
•Existing storage is approx.
120 feet (too short)
•Poor utilization because
peak hour queues extend
beyond turn bay
•Extend turn bay
approximately 200 feet to
2nd driveway to increase
utilization and reduce
queues
•Total Project Cost ($75,000)
SH 114 Ramp Reversal
SH 114 Ramp Reversal
Project Cost: $3,000,000
(Approx. $1.5M per ramp, includes potential for auxiliary lanes)
SH 114 Ramp Reversal
Looking East under the N. Carroll Avenue Bridge
SH 114 Ramp Reversal
Looking East under the N. Carroll Avenue U-Turn Bridge
-Avoid U-Turn bridge abutment
SH 114 Ramp Reversal
Looking East just past N. Carroll Avenue U-Turn Bridge
-Note change in grade
SH 114 Ramp Reversal
Looking East toward location of proposed on-ramp
-Change in grade
-Sign relocations