A Sketch Planning Assessment of Managed-Lane Options for the I-5 Freeway Corridor Master Plan

William R. Loudon,

DKS Associates

Overview of Analysis

Purpose To assess the potential of managed-lane strategies To determine what impact each could have on

vehicular demand and LOS on I-5 in 2035

Approach Sketch-planning adjustment of model results Optimistic but reasonable assumptions used about

each Draw on reported experiences when available

Managed Lane Options

High Occupancy Vehicle (HOV) Lanes High Occupancy Toll (HOT) Lanes Truck-Only Lanes

TABLE 1 Summary of the Potential Effects Managed-Lanes on I-5 General Purpose (GP) Lanes

Northbound PM Peak Hour

Percent Reduction in HBW Vehicle Trips

from Major Employment Sites

Initial Reduction in PCEs from GP

lanes on I-5

Net Reduction in PCEs from GP Lanes after

Reassignment of Demand

Percent Reduction in GP Lane PCEs

Resulting GP Volume (PCEs)

per Lane

Baseline None None None None 1200 to 2600

HOV Lane 5% to 10% 450 to 1300 250 to 750 6% to 18% 1000 to 2300

HOT Lane 5% to 10% 550 to 1600 300 to 870 7% to 21% 950 to 2200

Truck-Only Lane

None 160 to 460 80 to 300 2% to 6.5% 1100 to 2450

Southbound PM Peak Hour

Percent Reduction in HBW Vehicle Trips

from Major Employment Sites

Initial Reduction in PCEs from GP

lanes on I-5

Net Reduction in PCEs from GP Lanes after

Reassignment of Demand

Percent Reduction in GP Lane PCEs

Resulting GP Volume (PCEs)

per Lane

Baseline None None None None 1200 to 2150 HOV Lane 5% to 10% 500 to 1000 450 to 820 7% to 20% 950 to 2000

HOT Lane 5% to 10% 750 to 1600 480 to 950 12% to 32% 800 to 1900 Truck-Only Lane

None 200 to 500 120 to 400 3% to 12% 1100 to 2050

PCE – Passenger-car equivalents

Potential Effects of Managed Lanes

HOV Lanes in US

National Experience:

I-394

I-25SR-91 &

I-15

I-10 &US-290

I-15

Yellow – HOV Lanes

Red – HOT Lanes

124 HOV Facilities in the US

I-95I-95

HOV HOV Peak Hr HOV HOV Peak HrI-5 to SR 167 NB 2.13 2 L 2+ Stripe 0 6am-7am 0 5pm-6pmI-5 to SR 167 SB 2.13 2 L 2+ Stripe 564 6am-7am 690 5pm-6pmSR 167 to I-90 NB 8.32 2 L 2+ Stripe 1448 6am-7am 984 4pm-5pmSR 167 to I-90 SB 8.32 2 L 2+ Stripe 563 6am-7am 1629 4pm-5pmSR 522 to SR 524 NB 3.16 2 L 2+ Stripe 166 6am-7am 1255 4pm-5pmSR 522 to SR 524 SB 3.16 2 L 2+ Stripe 177 6am-7am 86 4pm-5pmI-405 to 15th St Northeast NB 10.4 2 L 2+ Stripe 812 7am-8am 450 3pm-4pmI-405 to 15th St Northeast SB 10.4 2 L 2+ Stripe 174 7am-8am 837 3pm-4pmNortheast 51st St to Northup Way EB 3.44 2 R 2+ Stripe and Dash 1116 7am-8am 965 3pm-4pmNortheast 51st St to Northup Way WB 3.44 2 R 2+ Stripe and Dash 765 7am-8am 1019 3pm-4pm78th Ave Northeast to 112th Ave Northeast WB 2.04 2 R 3+ Stripe and Dash 610 7am-8am 662 3pm-4pmNorth 115th Street to SR 523 NB 1.66 2 R Bus Only Stripe and Dash NA NA NA NAKent Des Moines Road to S 260th St NB 2.82 2 L 2+ Stripe NA NA NA NAS 160th St to S 260th St SB 6.41 2 L 2+ Stripe NA NA NA NAS 312th St to S 320th St NB 0.5 2 L 2+ Stripe NA NA NA NAS 308th St to S 320th St SB 0.75 2 L 2+ Stripe NA NA NA NASouth Cloverdale St to East Marginal Way NB 1.42 2 L 2+ Stripe 571 7am-8am 113 4pm-5pmSouth Cloverdale St to East Marginal Way SB 1.42 2 L 2+ Stripe 99 7am-8am 455 4pm-5pmNortheast 135th St to Northeast 145th Street NB 0.56 2 R 2+ Stripe and Dash NA NA NA NANortheast 145th Street to 73rd Ave Northeast SB 3.27 2 R Bus Only Stripe and Dash NA NA NA NANortheast 165th Street to 73rd Ave Northeast NB 2.19 2 R Bus Only Stripe and Dash NA NA NA NA

No CDR data for SR 16Select CDR data for SR 99 (no data for locations where HOV is found)Select CDR data for SR 522 (no data for locations where HOV is found)

SR 520

SR 167

SR 522

HOV Lane Location

I- 405

AM Peak Hour Volume PM Peak Hour VolumeFacility

SR 509

SR 99

Direction SegmentLength

(mi)Restrictions Separation Type

# GP Lanes

Washington HOV Lanes on Six-Lane Roadways

HOV Lanes – Analysis Methodology Develop and apply reasonable percentages

of HOV-eligible vehicles from peer review Estimate mode shift to and from

employment sites based on reported experiences

Estimate shift in HBW vehicle trips Estimate HOV and mixed-flow lanes LOS

based on estimates of mode shift and HOV lane use

HOT Lanes in US

Washington HOT Lanes on SR 167

US I-10 (13 miles) and US 290 (13.5 miles) in Houston SR 91 (10 miles) and I-15 (8 miles) in Southern California I-394 in Minneapolis (11 miles) I-25 in Denver (6.5 miles) I-15 in Salt Lake City (38 miles) I-95 in Miami (21 miles)

HOT Lanes – Analysis Methodology Develop diversion rates from mixed-flow to

HOT lanes based on available lane capacity Apply diversion rates to future forecasts of

I-5 volume with HOV to get estimates of HOT lane usage and mixed-flow lane usage

Estimate HOT and mixed-flow lanes LOS based on estimates of HOT lane use

Truck-Only Lanes in US

New Jersey Turnpike* (I-95) – 32 miles with toll California (I-5) – 2.4 miles including tunnel Louisiana (Clarence Henry Truckway) – 3.5 mile

intermodal connector Massachusetts (South Boston Haul Road) – 1.5 mile

tunnel Six truck-only ramps, bridges (3 tolled) or bypasses

of less than one mile

* Actually has passenger-car-only lanes. Passenger cars can use the truck lanes.

Truck-Only Lanes – Analysis Methodology

Use regional model to get estimate of truck volumes by time period

Develop reasonable diversion rates for trucks from mixed-flow to truck-only lanes

Estimate truck-only and mixed-flow lanes LOS based on estimates of truck-only lane use

TABLE 1 Summary of the Potential Effects Managed-Lanes on I-5 General Purpose (GP) Lanes

Northbound PM Peak Hour

Percent Reduction in HBW Vehicle Trips

from Major Employment Sites

Initial Reduction in PCEs from GP

lanes on I-5

Net Reduction in PCEs from GP Lanes after

Reassignment of Demand

Percent Reduction in GP Lane PCEs

Resulting GP Volume (PCEs)

per Lane

Baseline None None None None 1200 to 2600

HOV Lane 5% to 10% 450 to 1300 250 to 750 6% to 18% 1000 to 2300

HOT Lane 5% to 10% 550 to 1600 300 to 870 7% to 21% 950 to 2200

Truck-Only Lane

None 160 to 460 80 to 300 2% to 6.5% 1100 to 2450

Southbound PM Peak Hour

Percent Reduction in HBW Vehicle Trips

from Major Employment Sites

Initial Reduction in PCEs from GP

lanes on I-5

Net Reduction in PCEs from GP Lanes after

Reassignment of Demand

Percent Reduction in GP Lane PCEs

Resulting GP Volume (PCEs)

per Lane

Baseline None None None None 1200 to 2150 HOV Lane 5% to 10% 500 to 1000 450 to 820 7% to 20% 950 to 2000

HOT Lane 5% to 10% 750 to 1600 480 to 950 12% to 32% 800 to 1900 Truck-Only Lane

None 200 to 500 120 to 400 3% to 12% 1100 to 2050

PCE – Passenger-car equivalents

Conclusions

•HOV and HOT lanes are worth additional consideration•Truck lanes would do have sufficient benefit to warrant restriction

Conclusions (Continued)

Sketch-planning methods can help evaluate managed-lane options in a cost-effective manner to support a phased decision-making process.

Reported experiences from other managed-lane systems can be used to produce reasonable estimates of potential for managed-lanes options.

The approach allowed for quick screening of options in the I-5 corridor in the initial phase of the master plan.