Planning and Preliminary Engineering Guide For Using the Highway Capacity Manual NCHRP 7-22 Workshop.

Planning and Preliminary Engineering Guide For Using the Highway Capacity Manual
NCHRP 7-22 Workshop

Agenda The Project (9:00 AM) Overview of the Guide (9:30 AM)
Case Studies Long Range Regional Plan Update (10:30 AM) Freeway Master Plan (11:30 AM) Urban Street BRT Project Planning (2:00 PM) System Performance Monitoring (2:45 PM) Wrap Up (3:15 PM)

1. NCHRP 7-22 Project

NCHRP 7-22 To develop a guide to help planners take advantage of the HCM to improve their results. Status Stakeholder workshops held to identify planning needs and how the HCM might help. Initial rough draft guide for stakeholder review (October) Revised draft guide for panel review in December. Final guide submitted for publication June 2015

The People The Research Team
Kittelson & Associates - Rick Dowling, Paul Ryus North Carolina State University - Bastian Schroeder University of Idaho - Michael Kyte Stantec – Tom Creasey The Panel The Panel Dirk Gross (Ohio) (Chair) Tyrone Scorsone (CSI) Robert Bryson (Milwaukee) Brian Dunn (Oregon ) Jessie Jones (Arkansas) Subrat Mahapatra (Maryland) Erik Ruehr (VRPA) Andrew Wolfe (SUNY) Doug McLeod (Florida) Jeremy Raw (FHWA)

2. Overview of Guide 09:30

Contents Part I - How To Use the Guide
Long and Short Range Areawide Planning Project Traffic and Environmental Studies Highway Performance Monitoring Part 2 – Procedures Part 3 – Case Studies Long Range Regional Transportation Plan Analysis Freeway Future Conditions Analysis Analysis of BRT Project on Urban Street Roadway System Monitoring

Part 1- Gateway to the Guide
Areawide Planning Analysis Task Part 2 Reference Part 3 Case Studies Input to Travel Demand Models Estimation of highway segment capacities, and free-flow speeds Section O4 Ex. I.1 Traffic Assignment Module within the Travel Demand Model Volume-Delay functions for the estimation of congested speeds Section O5 Ex. 1.2 Post Processing Travel Demand Model Outputs Obtain more accurate speed estimates for air quality analyses Ex. I.3 Spotting auto v/c and LOS hot spots (quick screening) Ex. I.4 Estimation of delay based on agency policy Ex. I.5 Estimation of queuing Interpretation of results Ex. I.6 Travel time reliability analysis Ex. 1.7 Estimation of multimodal quality of service for autos, trucks, transit, bicycles, and pedestrians Ex. I.8 Ex. 1.9 Corridor Analyses Section O6 -

Project Impact & Alternatives Analysis Task Part 2 Reference Part 3 Case Studies Input to Travel Demand Models (if used) Estimation of highway capacities, and free-flow speeds Sections O4 Ex. I.1 Traffic Assignment Module within the Demand Model (if used) Volume-Delay functions for congested speeds Section O5 Ex. 1.2 Input to Microsimulation Model (if used) Estimation of free-flow speeds Section O4 Microsimulation Model Validation and Error Checking (if used) Capacity estimates for error checking simulated bottlenecks Project Impact & Alternatives Analyses Estimating segment speeds for air quality and noise analyses Sections E-H Case Studies 2-3 Estimating auto intersection utilization (v/c) Sections H-K Estimation of delay Estimation of queuing Interpretation of results Sections E-K Travel time reliability analysis Estimation of multimodal quality of service for autos, trucks, transit, bicycles, and pedestrians Corridor Analyses Section O6 -

Performance Monitoring Task Part 2 Reference Part 3 Case Studies Estimation of monitoring site capacities, and free-flow speeds Sections O4 Ex. IV.1 For Volume Only Monitoring Sites Estimation of speeds Section O5 Ex. IV.2 For Travel Time Only Monitoring Segments Estimation of volumes Ex. IV.3 Performance Analyses Quality Assurance/Quality Control Ex. IV.4 Auto and Truck VMT Ex. IV.5 Auto and Truck VMT by LOS Estimation of delay Estimation of queuing Travel time reliability analysis Estimation of multimodal quality of service for trucks, transit, bicycles, and pedestrians

Part 2 - Procedures Input Data Facilities Intersections Other
Default Values Generalized Service Volume Tables Working with Traffic Demand Data Intersection Traffic Control Guidance for Freeways Guidance for Multilane Highways Guidance for Two-Lane Highways Guidance for Urban Streets Guidance for Signalized Intersections Guidance for Stop-Controlled Intersections Guidance for Roundabouts Guidance for Interchange Ramp Terminals Guidance for Off-Street Pathways Guidance for Corridors Guidance for Areas and Systems Input Data Facilities Intersections Other

Part 2 – Section E: Freeway Procedures
E1. Overview E2. Computational Tools E3. Data Needs E4. Estimating Inputs Free flow Speed Capacity E5. Performance Measures Speed Level of Service Queues Reliability

First Page - Intro

Freeway Data Needs Required to Estimate Input Data (units) FFS Cap Spd
Required to Estimate Input Data (units) FFS Cap Spd LOS Que Rel Comments/Defaults Segment design geometry • Percent heavy vehicles (%) 10% (rural), 5% (urban) Number of directional lanes Must be provided Peak hour factor (decimal) 0.88 (rural), 0.95 (urban) Driver pop factor (decimal) 1.00 Segment length (mi) Directional demand (veh/h)

Typical Procedures

Part 2 – Section H: Urban Street Procedures
H1. Overview H2. Computational Tools H3. Data Needs H4. Segment Performance H5. Intersection Perform. H6. Facility Performance

First Page

Urban Street Data Needs
Input Data (units) FFS Cap Spd LOS MM-LOS Que Rel Comments/ Defaults Posted Speed Limit (mi/h) • required Intersection Data Analysis Period Length (h) 0.25 h Segment length (mi) Directional demand (veh/h) Cross-section, bus stops Seasonal demand data Defaults in appendix Incident data Local weather history Source in appendix Workzone probability

Typical Procedure

Part 2 Section I – Signalized Intersections
I1. Overview I2. Computational Tools I3. Data Needs & Limits I4. Performance Estimation Screening – Critical Lane Vol. v/c ratio Delay LOS Queue Reliability (sensitivity analysis) Bike/Ped LOS – see Section M

Signalized Intersection Data Needs
Required to Estimate Input Data (units) Cap Del LOS MMLOS Que Rel Comments/Defaults Number of turn lanes • n/a required Other geometry Defaults provided Signal Timing (cycle, g/c) Peak Hour Factor (decimal) 0.88 (rural), 0.95 (sub.) Percent heavy vehicles (%) 10 (rural), 5 (suburban) Turning demands (veh/h) Other demands (ped, park) Analysis Period Length (h) 0.25 h

Part 2 Section O – Areawide Analyses
O1. Overview O2. Computational Tools O3. Data Needs O4. Estimate Demand Model Inputs Free-Flow Speed Capacity O5. Performance Measures Auto – V/C, Speed, VHT, Delay, LOS, Density, Queue, Reliability.

Data Needs – Areawide Analysis
Required to Estimate Input Data (units) FFS Cap Spd Que Rel Comments/Defaults Facility Type • Defaults by area and facility type Segment design geometry Terrain type Must be provided Percent heavy vehicles (%) 10% (rural), 5% (urban) Peak hour factor (decimal) 0.88 (rural), 0.95 (urban) Driver pop factor (decimal) 1.00 Number of directional lanes Segment length (mi) Directional demand (veh/h) Output of Travel Model

“No-Fault” Capacity Look Up Table
Facility Type Area Type Free-Flow Speed (mph) G/C HCM PC Capacity (veh/ln) 90% PC Capacity (veh/ln) 80% PC Capacity (veh/ln) Freeway Downtown 55 n/a 2250 2000 1800 Urban 60 2300 2100 Suburban 65 2350 1900 Rural 70 2400 2200 Arterial 25 0.45 860 800 700 35 45 0.41 780 600 Rural Multi-Lane 1700 Rural 2-Lane 1600 1400 1300 Collector 30 0.37 1500

Multimodal LOS Dashboard – For Systems
Area Type Facility Type Mode LOS A-C LOS D LOS E LOS F Total Urban Freeways Auto 7% 24% 38% 31% 100% Truck 4% 20% Non-Freeway 16% 34% 5% 22% Transit 10% 29% Bicycle 12% 37% 21% Pedestrian

Comments So Far? Outline and Contents of Guide (Part 1, 2, 3)
What do you like so far? What do you dislike? What is missing?

3. Case studies 10:30

Case Study #1 – Regional Planning

Case 1 - LRTP Fresno COG 2040 Regional Transportation Plan - 6,000 square miles - 1 million population

Objectives Conduct transportation performance and investment alternatives analysis required to update 2040 LRTP Auto, truck, bus, bicycle, and pedestrian analyses to be performed. Travel Demand Forecasting Model to be Used

Example Problems Example Problems that Develop Demand Model Inputs
Example I.1 – Estimation of Free-Flow Speeds and Capacities Example I.2 – HCM Based Volume-Delay Functions Example Problems Post Processing Demand Model Outputs Example I.3 – Estimating Speeds for Air Quality & Noise Analysis Example I.4 – Screening for Auto V/C and LOS Hot Spots Example I.5 – Predicting Queues & Delay Example I.6 – Interpretation of Results Example I.7 – Prediction of Reliability Example I.8 – Transit, bicycle, and pedestrian LOS screening Example I.9 – Truck LOS screening

Example I.1 – estimating Free-flow Speeds & Capacities
Objective To develop lookup table of free-flow speeds and capacities for coding the highway network Approach Step 1: Identify facility categorization scheme Step 2: Determine free-flow speeds Step 3: Determine capacities

Picking facility TYpes
Area Type Free-Flow Speed (mi/h) Capacity (veh/ln) Freeway Downtown Urban Suburban Rural Principal Highway Rural Multi-Lane Rural Two-Lane Minor Highway Arterial Collector

For Free-Flow Speeds Consult Appropriate HCM Chapter for Procedure, or
Use Posted Speed Limit + 5 mph

Use “No-Fault” Capacity Table from part 2 - Section o
Facility Type Area Type Free-Flow Speed (mph) G/C HCM PC Capacity (veh/ln) 90% PC Capacity (veh/ln) 80% PC Capacity (veh/ln) Freeway Downtown 55 n/a 2250 2000 1800 Urban 60 2300 2100 Suburban 65 2350 1900 Rural 70 2400 2200 Arterial 25 0.45 860 800 700 35 45 0.41 780 600 Rural Multi-Lane 1700 Rural 2-Lane 1600 1400 1300 Collector 30 0.37 1500 Arterial/Collector assume 1900 ideal sat flow rate

HCM PC Capacity (veh/ln)
Pick 80% HCM PC Capacity Facility Type Area Type Free-Flow Speed (mph) G/C HCM PC Capacity (veh/ln) 90% PC Capacity (veh/ln) 80% PC Capacity (veh/ln) Freeway Downtown 55 n/a 2250 2000 1800 Urban 60 2300 2100 Suburban 65 2350 1900 Rural 70 2400 2200 Arterial 25 0.45 860 800 700 35 45 0.41 780 600 Rural Multi-Lane 1700 Rural 2-Lane 1600 1400 1300 Collector 30 0.37 1500 Arterial/Collector assume 1900 ideal sat flow rate

Free-Flow Speed (mi/h)
Example Result Facility Type Area Type Free-Flow Speed (mi/h) Capacity (veh/ln) Freeway Downtown 55 1800 Urban 60 Suburban 65 1900 Rural 70 Principal Highway Rural Multi-Lane 1700 Rural Two-Lane 1300 Minor Highway 45 1500 Arterial 25 700 35 600 Collector 30

Comments? Example I.1 – Creation of free-flow speed and capacity lookup tables

Example #I.2 – HCM Based Volume-delay Functions
Objective To select an HCM based volume-delay function for demand model Approach Step 1: Select volume-delay function type BPR and Akcelik Step 2: Set parameters Match Speed at Capacity Compute Akcelik parameter Compute BPR parameter Step 3: Select preferred volume-delay function

Akcelik Where: T0 = Free-flow travel time X = volume/capacity ratio
J = calibration parameter L = length of the link

BPR Where: T0 = Free-flow travel time X = volume/capacity ratio
A = speed at capacity calibration parameter B = rate of travel time increase calibration parameter

Smooth vs Rough Pipe BPR Akcelik Everybody waits their turn here.
goes slow entire length T Free-Flowing here

Splitting Smooth & Rough PipeS
BPR Akcelik 0.5 T or T T or 2T T Problem for DTA, No Problem for SUE Models No Problem for DTA, Problem for SUE Models

Comparing Speeds

Comparing Speeds Speed at Capacity

Calibrating to Speed at Capacity
Akcelik BPR

Free-Flow Speed (mi/h) HCM Speed at Capacity (mi/h)
Calibrated Curves Facility Type Area Type Free-Flow Speed (mi/h) Capacity (veh/ln) HCM Speed at Capacity (mi/h) BPR “a” Parameter Akcelik “J” Parameter Freeway Downtown 55 1800 50.0 0.10 3.31E-06 Urban 60 51.1 0.17 8.43E-06 Suburban 65 1900 52.2 0.25 1.42E-05 Rural 70 53.3 0.31 2.00E-05 Principal Highway Rural Multi-Lane 1700 47.1 9.30E-06 Rural Two-Lane 1300 47.0 9.58E-06 Minor Highway 45 1500 39.6 0.14 9.18E-06 37.0 0.22 2.31E-05 Arterial 25 700 23.2 0.08 9.63E-06 35 31.6 0.11 9.45E-06 600 Collector 30 27.4 0.09 1.00E-05

All Get Same Speed at Capacity

Comparing Travel Times

Comparing to HCM Akcelik vs. HCM

Comments? Example I.2 – Selection of Volume-Delay Functions

Example I.3 – Speeds for Air Quality Analysis
Objective: to develop a speed-flow equation that accurately reflects queueing delays for post-processing travel demand model outputs for air quality analysis purposes. Procedure: Step 1: Identify free-flow speeds and capacities Step 2: Select appropriate Akcelik parameters for links Step 3: Compute speed for link Step 4: Interpretation of Results

Post Processing Model Speeds
Link ID Type v/c Original Model Speed (mi/h) A001 Freeway-Urban 1.14 48 A002 Arterial-Urban 0.83 33 A003 Collector-Urban 0.98 26 A004 Freeway-Rural 0.73 67 A005 Highway-Rural 0.44 55 A006 Collector-Rural 0.19 45

80% PC Capacity (veh/h/ln) Segment Capacity (veh/h)
Post Processing (2) Link ID Length (mi) Type Demand (veh/h) Free Speed (mi/h) 80% PC Capacity (veh/h/ln) Akcelik “J” Segment Capacity (veh/h) v/c Speed (mi/h) A001 0.85 Freeway-Urban 8,220 60 1800 8.40E-06 7,200 1.14 10.0 A002 0.21 Arterial-Urban 1,740 35 700 9.34E-06 2,100 0.83 18.7 A003 1.34 Collector-Urban 1,170 30 600 1,200 0.98 26.2 A004 2.50 Freeway-Rural 2,790 70 1900 1.99E-05 3,800 0.73 68.7 A005 4.50 Highway-Rural 1,490 55 1700 3,400 0.44 51.5 A006 7.30 Collector-Rural 250 45 1300 2.31E-05 1,300 0.19 44.8

Original Model Speed (mi/h)
Results – New Speeds Link ID Type v/c Original Model Speed (mi/h) Revised Speed (mi/h) A001 Freeway-Urban 1.14 48 10 A002 Arterial-Urban 0.83 33 19 A003 Collector-Urban 0.98 26 A004 Freeway-Rural 0.73 67 69 A005 Highway-Rural 0.44 55 52 A006 Collector-Rural 0.19 45 Short vs long segments

Original Model Speed (mi/h)
Interpretation Short vs long segments Link ID Type v/c Original Model Speed (mi/h) Revised Speed (mi/h) A001 Freeway-Urban 1.14 48 10 A002 Arterial-Urban 0.83 33 19 A003 Collector-Urban 0.98 26 A004 Freeway-Rural 0.73 67 69 A005 Highway-Rural 0.44 55 52 A006 Collector-Rural 0.19 45 Long (> 1mile)

Comments? Example I.3 – Refining speed estimates for air quality analysis.

Example I.4 – Screening for Auto Hot Spots
Objective: To identify auto volume/capacity ratio and level of service problem spots within the highway system. Procedure: Step 1: Compute v/c for links Step 2: Estimate LOS for links

Auto V/C LOS Table Facility Type Area Type Free-Flow Speed (mi/h) LOS A-C LOS D LOS E Freeway Rural 65 0.70 0.85 1.00 Urban 0.65 Multilane Highway 60 Two Lane Highway N.D. Arterial 45 0.50 0.90 25-35 0.30 0.80

V/C LOS Lookup Table Facility Type Area Type Free-Flow Speed (mi/h) LOS A-C LOS D LOS E Freeway Rural 65 0.70 0.85 1.00 Urban 0.65 Multilane Highway 60 Two Lane Highway Arterial 45 0.50 0.90 25-35 0.30 0.80

Segment Capacity (veh/h)
Example V/c & LOS Comp. Link ID Length (mi) Type Demand (veh/h) Free Speed (mi/h) Segment Capacity (veh/h) v/c LOS A001 0.85 Freeway-Urban 8,220 60 7,200 1.14 F A002 0.21 Arterial-Urban 1,740 35 2,100 0.83 E A003 1.34 Collector-Urban 1,170 30 1,200 0.98 A004 2.50 Freeway-Rural 2,790 70 3,800 0.73 D A005 4.50 Highway-Rural 1,490 55 3,400 0.44 A-C A006 7.30 Collector-Rural 250 45 1,300 0.19

Comments? Example I.4 – V/C and LOS Screening

Example I.5 – Density, Queues, delay
Objective: To compute and report the density of traffic, hours spent in queues, and hours delay within the highway system. Procedure: Step 1: Compute Density Step 2: Compute Vehicle-Hours in Queue Step 3: Compute Vehicle-Hours of Delay Step 4: Interpretation of Results

Density VEH-HRS DELAY Where: D = density (pc/mi/ln) v = demand (veh/h)
N = number of lanes S = speed (mi/h) PCE = passenger car equivalent 𝐷=1.2∗ 𝑣 𝑁∗𝑆 VEH-HRS DELAY Where: VHD = Vehicle-hours delay V = demand (veh/h) L = length of link (mi) S = speed (mi/h) SP = agency’s policy minimum acceptable speed for facility (mi/h) 𝑉𝐻𝐷= 𝑣∗𝐿 𝑆 − 𝑣∗𝐿 𝑆 𝑃

Veh-Hrs In Queue Sum of vehicle-hours spent on links with
v/c > 1.00 or speed below the speed at capacity. Sum of vehicle-hours delay at intersections Average delay at intersection (converted into hours) multiplied by total vehicles entering intersection. Exclude free right turn volumes

Comments? Example I.5 – Density, Delay, Queue Calculations

Example I.6 – Reporting System Results
Inputs Outputs Link ID Type L v c FFS CSpd S v/c VMT VHT VHD VHQ A001 Freeway-Urban 0.85 8,220 7,200 60 51.1 10.0 1.14 6,987 700 563 A002 Arterial-Urban 0.21 1,740 2,100 35 31.6 18.7 0.83 365 20 8 A003 Collector-Urban 1.34 1,170 1,200 30 27.5 26.2 0.98 1,568 3 A004 Freeway-Rural 2.50 2,790 3,800 70 53.3 68.7 0.73 6,975 102 A005 Highway-Rural 4.50 1,490 3,400 55 47.1 51.5 0.44 6,705 130 A006 Collector-Rural 7.30 250 1,300 45 37.0 44.8 0.19 1,825 41 Total 24,425 1,051 574

Reporting System LOS Area Type Facility Type Mode LOS A-C LOS D LOS E
LOS F Total Urban Freeways Auto 7% 24% 38% 31% 100% Truck 4% 20% Non-Freeway 16% 34% 5% 22% Transit 10% 29% Bicycle 12% 37% 21% Pedestrian

Comments? Example I.6 – Reporting System Results

Example I.7 – Prediction of Reliability
Objective: To identify auto reliability problem spots and causes within the highway system. Procedure: Step 1: Compute average annual TTI for links Step 2: Compute average annual TTI for system Step 3: Compute 95th percentile annual TTI for system Step 4: Interpretation of results

Travel Time Reliability
Number of Trips Travel Time (min)

Characterizing Reliability
Mean Free Flow 95th Percentile Number of Trips Trips < 45 mph Travel Time (min)

The TTI Statistic 𝑇𝑇𝐼 95 = 𝑇𝑇 95 𝑇𝑇 𝐹𝑟𝑒𝑒−𝐹𝑙𝑜𝑤 Free Flow Mean
𝑇𝑇𝐼 95 = 𝑇𝑇 95 𝑇𝑇 𝐹𝑟𝑒𝑒−𝐹𝑙𝑜𝑤 Mean Free Flow 95th Percentile Number of Trips Travel Time (min)

The Percent < 45 Mph 𝑃𝑇 45 = 𝑇𝑟𝑖𝑝𝑠 <45 𝑇𝑜𝑡𝑎𝑙 𝑇𝑟𝑖𝑝𝑠 Free Flow
𝑃𝑇 45 = 𝑇𝑟𝑖𝑝𝑠 <45 𝑇𝑜𝑡𝑎𝑙 𝑇𝑟𝑖𝑝𝑠 Free Flow Number of Trips Trips < 45 mph Length/45 Travel Time (min)

Reliability Prediction
Average Annual TTI 𝑻𝑻𝑰 𝒎 =𝟏+𝑭𝑭𝑺∗(𝑹𝑫𝑹+𝑰𝑫𝑹) Recurring Delay Rate 𝑹𝑫𝑹= 𝟏 𝑺 − 𝟏 𝑭𝑭𝑺 Incident Delay Rate 𝑰𝑫𝑹= 𝟎.𝟎𝟐𝟎− 𝑵−𝟐 ∗𝟎.𝟎𝟎𝟑 ∗ 𝑿 𝟏𝟐 Where: TTIm = average annual mean travel time index (unitless) FFS = free-flow speed (mi/h) RDR = Recurring delay rate (h/mi) IDR = Incident Delay Rate (h/mi S = peak hour speed (mi/h) N = number of lanes one direction X = peak hour v/c

Reliability Stats 𝑻𝑻𝑰 𝟗𝟓 =𝟏+𝟑.𝟔𝟕∗𝐥𝐧( 𝑻𝑻𝑰 𝒎 )
𝑷𝑻 𝟒𝟓 =𝟏−𝐞𝐱𝐩(−𝟏.𝟓𝟏𝟏𝟓∗ 𝑻𝑻𝑰 𝒎 −𝟏 ) where TTI95 = the 95th percentile TTI; PT45 = the percent of trips that at speeds less than 45 mph TTI95 is the ratio of the 95th percentile highest travel time to the free-flow travel time

Reliability Stats (2) Link ID Type VHT(FFS) RDR IDR TTIm VHTm TTI95
Fwy-Urban 116 8.34E-02 6.86E-02 10.13 1,179 A002 Art-Urban 10 2.49E-02 1.78E-03 1.93 20 A003 Coll-Urban 52 4.79E-03 1.48E-02 1.59 83 A004 Fwy-Rural 100 2.73E-04 4.91E-04 1.05 105 A005 Hiwy-Rural 122 1.23E-03 1.00E-06 1.07 130 A006 Coll-Rural 41 8.02E-05 5.12E-11 1.00 Total or Ave. 441 3.53 1,558 5.63 1,323 57% 43% 85%

Reliability Good? Areawide Results 95%TTI = 5.63
% Trips < 45 mph = 85% Good, Bad, or Ugly? Recent TRB Paper Level of Service 5% Speed 95% TTI A >60 mi/h <1.08 B 55-60 C 45-55 D 35-45 E 25-35 F <=25 >= 2.60

Comments? Example I.7 – Estimating Reliability

Example I.8 –transit, Bike, Ped LOS
Objective: To screen for multimodal LOS problems in highway system Procedure: Step 1: Select transit, bike, ped service volume tables Step 2: Screen for transit LOS problems Step 3: Screen for bicycle LOS problems Step 4: Screen for pedestrian LOS problems Interpretation of Results Agency policies vs. LOS

Transit LOS The most important factor = Frequency of Service Next most important factor = Speed of Transit Other factors = pedestrian environment, bus stop amenities Bus Frequency LOS A-C LOS D LOS E LOS F 1 bus/hr N/A >35 mph <30 mph 2 buses/hr >25 mph 10-25 mph 3-10 mph <3 mph 3 buses/hr >11 mph 4-11 mph <4 mph 4 buses/hr >7 mph 2-7 mph <2 mph

Maximum Directional Auto Volume for Target Transit LOS (veh/h/ln)
Transit Serv. Vol. Table Area Type Buses/h Speed Limit (mi/h) Maximum Directional Auto Volume for Target Transit LOS (veh/h/ln) LOS A-C LOS D LOS E CBD 6 25 790 890 900 Urban 4 35 880 2 10 Suburban 45 860 1 N/A 720

Bicycle & Pedestrian LOS
Depends on: Geometric Characteristics Bike lane, sidewalks, buffer strip, etc. Auto Volume Auto Speed Percent Trucks

Bike LOS Max Auto Volumes (veh/h/ln) Features 6' Bike lane 50% Parking
45 mph PSL 35 mph PSL 25 mph PSL Bike LOS A-C Bike LOS D Bike LOS E Bike LOS E Bike LOS D Features 30 160 700 50 250 v/c>1 150 660 ✔ 210 330 890 80 350 120 560 680

Ped LOS Max Auto Volumes (veh/h/ln) 6' Bike lane 50% Parkg 6' Buffer
5' Sidewalk 55 mph PSL 25 mph PSL Ped LOS A-C Ped LOS D Ped LOS E N/A 10 340 60 390 720 ✔ 310 640 360 690 v/c>1 670 710 850 410 740 780

Multimodal LOS Issues What should be transit, bike, ped LOS when agency policy is not to provide for those services Low density areas How to estimate multimodal LOS when auto volumes make little or no difference? Code basic cross-sectional characteristics into demand model links Presence of bike lanes, parking, buffer strip, sidewalk Use GIS, color code links by LOS

Bike System LOS Map These are routes where agency would like to provide good Bike LOS. This is how they rated.

Comments? Example I.8 – Transit, Bike, Ped LOS

Example I.9 – Truck LOS Objective: To identify truck level of service problem facilities within the highway system. Procedure: Step 1: Select truck LOS table Step 2: Assign links to truck LOS table entries Step 3: Tally truck LOS results Step 4: Interpretation of results

Truck LOS Depends on : Peak hour truck speed (recurring congestion)
Probability of on-time arrival (reliability) Tolls Truck friendliness index Percent of legal loads and vehicles that can use facility Number of at-grade railroad crossings Goods movement functional class of facility Inter-regional facility Primary regional facility Supporting facility (feeds intermodal terminals)

Freeways and Rural Highways
Truck TTI LOS Lookup Truck TTI 95% TTI POTA %Ideal Class I Class II Class III Freeways and Rural Highways FFS = mi/h 1.05 1.18 99% 90% A 1.10 1.35 93% 86% B 1.15 1.51 81% 76% C 1.20 1.67 69% 63% D 1.25 1.82 60% 51% E 1.30 1.96 53% 41% F 2.10 48% 34% 1.40 2.23 43% 28% Truck LOS = function of (on-time arrival, travel time, toll, truck friendliness) Tables also for signalized urban streets (35-55 mph speeds)

Truck Speed to LOS Table
Truck Speed Class I Inter-Regional Class II Primary Route Class III Supporting Route Freeways and Rural Highways 50 mph D C 45 mph F E Signalized Urban Streets FFS = 55 mi/h 28 mph FFS = 45 mi/h 23 mph FFS = 35 mi/h 17 mph

Truck LOS Example Comps
Link ID Type Truck Demand (veh/h) Mixed TTI Truck Speed Adj Freight Class LOS A001 Freeway-Urban 411 6.01 1.1 6.61 I F A002 Arterial-Urban 122 1.87 2.06 II E A003 Collector-Urban 47 1.14 1.26 III A A004 Freeway-Rural 279 1.02 1.12 B A005 Highway-Rural 119 1.07 1.17 A006 Collector-Rural 15 1.00 1.10

Comments? Example I.9 – Truck LOS

Comments Case Study 1? Case Study #1 – Long Range Regional Plan

Case Study #2 – Freeway Project
11:30

Case 2 – Freeway Master Plan
4-6 Lane Interurban Freeway 70 miles long, Passes through 5 urban areas 7% grade over Cuesta Pass

objective To develop a Corridor Mobility Master Plan to identify current and future mobility problems in the corridor, and establish capital project priorities along the corridor.

Case 2 Example Problems Example II.1 – Screening for Service Volume Problems Example II.2 – Forecasting V/C Hot Spots Example II.3 – Estimation of Speed and Travel Time Example II.4 – Prediction of Unacceptable Auto LOS Spots Example II.5 – Estimation of Queues Example II.6 – Prediction of Reliability Problems

Example II.1 –Screening for Service Volume Problems
Objective: To focus the study on critical auto LOS supersections of freeway Approach: Step 1: Data requirements Step 2: Categorize facilities Step 3: Develop service volume look up table Step 4: Select focus supersections

Service Volume Tables Maximum traffic volumes that can be accommodated at a target LOS. Auto LOS tables Freeway, Multilane Hwy, Two-Lane Hwy, Urban Street Bus, Bicycle, Pedestrian LOS tables Truck LOS tables They hinge on many underlying assumptions Use as a Screening & Scoping Tool

Freeway service Volume Table
K- Factor D- Four-Lane Freeways Six-Lane Freeways LOS C LOS D LOS E 0.08 0.50 75,500 94,100 108,900 113,300 141,100 163,400 0.55 68,700 85,500 99,000 103,000 128,300 148,500 0.60 62,900 78,400 90,800 94,400 117,600 136,100 0.65 58,100 72,400 83,800 87,200 108,500 125,700 0.09 67,100 83,600 96,800 100,700 125,400 145,200 61,000 76,000 88,000 91,600 114,000 132,000 56,000 69,700 80,700 83,900 104,500 121,000 51,600 64,300 74,500 77,500 96,500 111,700 0.10 60,400 75,300 87,100 90,600 112,900 130,700 54,900 68,400 79,200 82,400 102,600 118,800 50,400 62,700 72,600 46,500 57,900 67,000 86,800 100,500 0.11 49,900 62,200 72,000 74,900 93,300 108,000 45,800 57,000 66,000 42,300 52,600 60,900 63,400 78,900 91,400

Minimum Peak Direction Volume Maximum Peak Direction Volume
Freeway Service Vols Level of Service Minimum Peak Direction Volume Maximum Peak Direction Volume LOS A-C 1510 veh/h/lan LOS D 1510 veh/h/ln 1880 veh/h/ln LOS E 2180 veh/h/ln LOS F infinity

Data Requirements Data Facility Type (freeway, highway)
Area type (urban, rural) Terrain type (level, rolling, mountain) AADT K-factor (pk.hr/AADT) D-Factor (directional factor) Split Facility into Supersections Combinations of sections With similar AADT, area type, terrain

Determine facility Type
Freeway (access controlled) Multilane highway

Select Service Vol Table
First verify HCM service volume tables apply. Adjust DSV (daily service volume) if necessary. Required Data Default Values Urban Freeways Rural Freeways Urban Highways Rural Highways K-Factor 0.08 – 0.11 0.09 – 0.12 0.08 – 0.12 D-Factor 0.50 – 0.65 %Trucks 5% 12% 8% %Buses 0% N/A %RVs PHF 0.95 0.88 0.93 Ramp Density (/mi.) 3 0.2 fp 1.00 0.85 1.0 Lane Width (ft.) 12 Lateral Clear (ft.) 6 FFS (mph) 65 60 Terrain Level or Rolling

Adjust for Local Conditions
HCM Table DSV= 𝑀𝑆𝐹 0 × 𝑁× 𝑓 𝐻𝑉 × 𝑓 𝑝 ×𝑃𝐻𝐹 𝐾×𝐷 × 𝐾 0 × 𝐷 0 𝑁 0 × 𝑓 𝐻𝑉,0 × 𝑓 𝑝,0 × 𝑃𝐻𝐹 0 Where: DSVi = daily service volume (veh/day) MSFi = maximum service flow (vphpl), HCM Exhibit for frwys , Exhibit for hwys N = number of lane in each direction fHV = adjustment factor for presence of heavy vehicles in traffic stream fp = adjustment factor for unfamiliar driver populations PHF = peak-hour factor K = proportion of daily traffic occurring in the peak hour of the day D = proportion of traffic in the peak direction during the peak hour of the day

Identify Focus SuperSections
Facility Type Area Type Terrain Future AADT Modified Max AADT (x 1,000) Future LOS LOS C LOS D LOS E A 4-ln Highway Urban Level 57,600 59,200 75,700 84,100 A-C B 4-ln Freeway 63,500 62,900 78,400 90,800 D C 4-Ln Freeway Rural 70,100 50,400 62,800 72,700 E 55,800 61,000 76,000 88,000 6-Ln Highway Mountain 44,500 52,500 67,100 74,500 F 58,700 65,800 82,000 94,900 G 58,800 57,900 72,100 83,500 H 32,400 I 4-Ln Highway 19,500 56,400 80,100

Result: Focus SuperSections
Section ID’s Focus SuperSections B – North of Arroyo Grande C – South of San Luis Obispo G – South of Paso Robles For Rest of this Case Study SB, PM Peak

Comments? Example II.1 – Use of Service Volumes to screen and scope planning analysis

Example II.2 – Forecasting V/C Bottlenecks
Objective: To forecast future auto v/c hot spots on facility. Approach: Step 1: Data requirements Step 2: Selection of defaults Step 3: Select study boundaries and time periods Step 4: Identify segment types Step 5: Estimate free-flow speeds Step 6: Estimate capacities Step 7: Assign section demands Step 8: Compute v/c ratios Step 9: Interpretation of Results

Selected SuperSection C Sections 1-3

Selected SuperSection C Sections 4-7

1. Data Requirements Peak hour factor (peak 15 minutes to peak hour)
Percent heavy vehicles Peak (K) factor (peak hour to daily) Segment Type (basis, weave, merge, diverge) Segment Length Lanes Demand (Mainline in, all ramps)

Defaults Required Data Default Values Urban Freeways Rural Freeways
K-Factor 0.08 – 0.11 0.09 – 0.12 D-Factor 0.50 – 0.65 %Trucks 5% 12% %Buses 0% %RVs PHF 0.95 0.88 Fp (Driver Population) 1.00 0.85 Lane Width (ft.) 12 Lateral Clearance (ft.) 6

Select Study Boundaries & Time Periods
Review historical information on congestion Select Peak Period and Direction Pick Southbound Direction, Weekday PM Peak period.

Identify Section Types
Freeway weave section Starts with on-ramp Ends with off-ramp AND Has auxiliary lane between the two ramps Freeway ramp section Starts with on-ramp, or ends with off-ramp, or both But no auxiliary lanes between on and off-ramps Freeway basic section Everything else Flow Basic Ramp Basic Ramp Basic Ramp Basic 1 2 3 4 5 6 7 No Weave Sections

Estimate Free-Flow Speeds
Use HCM Method 𝑭𝑭𝑺=𝟕𝟓.𝟒− 𝒇 𝑳𝑾 − 𝒇 𝑳𝑪 −𝟑.𝟐𝟐 𝑻𝑹𝑫 𝟎.𝟖𝟒 Or Use Posted Speed Limit 𝑭𝑭𝑺=𝑷𝑺𝑳+𝟓 𝒎𝒑𝒉 Where: FFS = free-flow speed (mi/h) fLW = adjustment for lane width (mi/h) fLC = adjustment for right side lateral clearance (mi/h) TRD = total ramp density (ramps/mi) PSL = Posted Speed Limit (mi/h)

Estimate Capacities 𝒄 𝒊 = 𝟐,𝟐𝟎𝟎+𝟏𝟎∗ 𝐦𝐢𝐧 𝟕𝟎, 𝑺 𝑭𝑭𝑺 −𝟓𝟎 𝟏+%𝑯𝑽/𝟏𝟎𝟎 ∗𝑪𝑨𝑭
𝒄 𝒊 = 𝟐,𝟐𝟎𝟎+𝟏𝟎∗ 𝐦𝐢𝐧 𝟕𝟎, 𝑺 𝑭𝑭𝑺 −𝟓𝟎 𝟏+%𝑯𝑽/𝟏𝟎𝟎 ∗𝑪𝑨𝑭 Where: Ci = capacity of section “I” (vph/ln) SFFS = Free-flow speed (mph) %HV = percent of heavy vehicles. CAF = a capacity adjustment factor that is used to calibrate the basic section capacity given in the HCM to account for influences of ramps, weaves, or other impacts. Section # C1 C2 C3 C4 C5 C6 C7 Type Basic Ramps Length (mi) 0.05 1.65 0.24 1.51 0.37 0.81 0.18 Capacity Adjust Factor 1.00 0.95 Adj Lane Capacity (vphpl) 2,221 2,110 Number of Lanes 2 Section Capacity (vph) 4,442 4,220

Assign Demands Compute Section Demands If Demand < Capacity
Sum the mainline in and on-ramp Subtract off-ramp If Demand > Capacity Do same as before Reduce demand to capacity Save up excess demand, add to next time period demand Flow 3,000 3,900 3,100 4,100 3,600 3,900 3,100 1 2 3 4 5 6 7 900 800 1,000 500 300 800

Constrain Demands Example for freeway with capacity = 4,000 vph Flow
Unconstrained 3,000 3,900 3,100 4,100 3,600 3,900 3,100 1 2 3 4 5 6 7 900 800 1,000 500 300 800

Constrain Demands Example for freeway with capacity = 4,000 vph Flow
Unconstrained 3,000 3,900 3,100 4,100 3,600 3,900 3,100 1 2 3 4 5 6 7 900 800 1,000 500 300 800 Constrained 3,000 3,900 3,100 4,000 3,511 3,811 3,029 1 2 3 4 100 5 6 7 900 800 1,000 489 300 782

Compute D/c and V/C Demand/Capacity ratio Volume/Capacity Ratio
Ratio of demand to capacity Volume/Capacity Ratio Ratio of capacity constrained demand to capacity Section # C1 C2 C3 C4 C5 C6 C7 Sect. Capacity (Ci) 4,442 4,220 Time Period 1 (16:00-16:15 ) Demand (di,1) 3,336 4,024 3,984 4,472 3,852 3,964 D/C Ratio 0.75 0.95 0.90 1.06 0.87 0.94 Time Period 2 (16:15-16:30) DEMAND (di,2) 3,791 4,573 4,175 4,981 3,802 3,929 0.85 1.08 1.18 0.86 0.93 Time Period 3 (16:30-16:45) DEMAND (di,3) 4,377 4,180 5,429 1.04 1.29 Time Period 4 (16:45-17:00) DEMAND (di,4) 2,881 3,632 3,597 5,228 3,902 3,999 0.65 0.81 1.24 0.88

Interpret Results D/C Contour Diagram
Flow D/C

Comments? Example Problem II.2 – Auto V/C Bottleneck Identification

Example II.3 – Estimation of Speed and Travel Time
Objective: To forecast speeds and travel times on freeway. Approach: Step 1: Estimate delay rates Step 2: Compute travel times and speeds Step 3: Interpretation of results 𝐷𝑅=𝐴 𝑥 3 +𝐵 𝑥 2 + 𝐶𝑥+𝐷 Where: DR = delay rate (secs/mi) X = volume/capacity ratio A, B, C, D = parameters

Speed Results Section # C1 C2 C3 C4 C5 C6 C7 FFTravel Rte (s/m) 55.4
Length (mi) 0.05 1.65 0.24 1.51 0.37 0.81 0.18 Time Period 1 (0-15 minutes) Delay Rate (s/mi) 1.7 10.1 6.8 31.3 5.4 9.2 Travel Rate (s/m) 57.0 65.5 62.2 86.6 60.8 64.6 Travel Time (sec) 2.9 108.1 14.9 130.8 22.5 52.3 10.9 Speed (mph) 62.1 54.9 58.0 41.6 59.2 55.8 59.4 Time Period 2 (15-30 minutes) Delay Rate (s/m) 4.8 36.3 67.2 4.9 8.7 60.2 91.6 122.6 60.3 64.1 3.0 151.2 15.5 185.1 22.3 51.9 60.0 39.3 55.7 29.4 59.7 56.2 Time Period 3 (30-45 minutes) 23.6 9.3 98.8 79.0 64.7 154.2 130.3 232.9 45.6 23.3

Speed Contour Diagram

Comments Example Problem II.3 – Freeway Speed and Travel Time Estimation.

Example II.4 –Unacceptable Auto LOS Hot Spots
Objective: To predict auto LOS problems Approach: Step 1: Estimate density and auto LOS Step 2: Interpretation of results Freeway Segments Level of Service Density (pc/mi/ln) A <= 11 B >11-18 C >18-26 D >26-35 E >35-45 F >45 or v/c>1.00 Density = 1.2* 𝑉𝑜𝑙𝑢𝑚𝑒/𝐿𝑎𝑛𝑒 𝑆𝑝𝑒𝑒𝑑

Comments? Example Problem II.4 – Freeway Auto LOS Analysis

Example II.5 – Estimation of Queues
Objective: To forecast queuing problems on freeway. Approach: 𝑄𝑢𝑒𝑢𝑒(𝑓𝑡)=𝑀𝑎𝑥(0, 𝐷𝑒𝑚𝑎𝑛𝑑 −𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 𝐷𝑒𝑛𝑠𝑖𝑡𝑦 ) Section Number 1 2 3 4 5 6 7 Length (mi.) 0.05 1.65 0.24 1.51 0.37 0.81 0.18 Number of Lanes Section Capacity (vph) 4,442 4,220 Time Period 1 (0-15 minutes) Demand (vph) 3,336 4,024 3,984 4,472 3,852 3,964 V/C Ratio 0.75 0.95 0.90 1.06 0.87 0.94 Density (vpmpl) 26.9 36.6 34.4 50.8 32.5 35.5 32.4 Estimated Queue (mi.) 2.48 Actual Queue (mi.) 0.73 0.24

Comments? Example Problem II.5 – Freeway Queuing Analysis

Example II.6 – Prediction of Reliability Problems
Objective: To forecast reliability for freeway. Approach: Step 1: Data requirements Step 2: Identify segment types Step 3: Identify demand variability Step 4: Identify weather events Step 5: Identify incidents Step 6: Identify work zones Step 7: define reliability analysis scenarios Step 8: Compute hourly travel times Step 9: Compute reliability statistics Step 10: Interpret results

Data for Reliability Analysis
Data Type Input or Default Values Data Source Volume (AADT) Input Caltrans/Travel Model Number of lanes Aerial Map Length (miles) Caltrans/Aerial Map K-Factor Caltrans D-Factor Seasonal Adjustment Factor Work Zone Capacity (vphpl) 1,600 HCM Exhibit 10-14 Incident Capacity Reduction HCM Exhibit 10-17 Work Zone Avg. Lane Closes 1 Default Rainfall Intensity (inches) Weather Underground Avg. Blocking Incident Duration (minutes) Avg. Non-blocking Incident Duration (minutes) Total Number of Blocking Incidents Total Number of Non-blocking Incidents Free-flow Speed Reduction for Light-Rain 6.00% Free-flow Speed Reduction for Heavy-Rain 12.00% Area Type Local Knowledge Analysis Period Facility Type HCM

Reliability Results Good, Bad, or Ugly? Section Computed 95%TTI Daily
AM (7-9) PM (4-6) C1 1.10 1.12 1.14 C2 1.89 1.75 C3 1.07 1.08 Good, Bad, or Ugly?

Reliability Results(2)
Section Computed 95%TTI Daily AM (7-9) PM (4-6) C1 1.10 B 1.12 1.14 C2 1.89 E 1.75 D C3 1.07 A 1.08 Draft FDOT LOS Scale Level of Service 5% Speed 95% TTI A >60 mi/h <1.08 B 55-60 C 45-55 D 35-45 E 25-35 F <=25 >= 2.60 Good, Bad, or Ugly?

Comments? Example Problem II.6 – Freeway Reliability Analysis

Comments Case Study 2? Case Study #2 – Freeway Master Plan

Case Study #3 – Urban Street BRT
14:00

Case 3 – Urban Street BRT Plan
14 mile urban street BRT to take 2 thru lanes

objective to identify the traffic, transit, pedestrian, and bicycle impacts of the proposed BRT project.

Case 3 Example Problems Example III.1 – Screening for Service Volume Problems Example III.2 – Screening for Auto Choke Points Example III.3 – Forecasting V/C Ratios Example III.4 – Auto and BRT Speeds/Travel Times Example III.5 – Predicting Queues Example III.6 – Predicting Reliability Problems Example III.7 – Transit, Bicycle, Pedestrian LOS

Example III.1 –Screening for Service Volume Problems
Objective: To focus the study on critical auto LOS supersections of BRT project Approach: Step 1: Divide BRT route into supersections Step 2: Obtain AADTs Step 3: Identify service volumes Step 4: Identify supersections for further analysis

Divide BRT Route into SuperSections
Divide route into supersections Divide at points where there are significant changes in: Posted speed limit Number of through lanes Median Demand

Supersections Street Limits Length (mi) AADT Speed Limit (mi/h)
Lanes + Median Telegraph Ave. Dwight to Woolsey 0.84 16,570 25 4 Telegraph Ave Woolsey to SR 24 0.80 18,340 30 SR 24 to 45th St. 0.60 16,540 5 45th St. to Broadway 2.01 16,230 International Bl. Lake Merritt to 23rd Ave 1.58 10,220 23rd Ave to 35th Ave. 0.87 13,370 35th Ave to High St. 0.51 15,910 High St. to Hegenberger 1.78 13,560 Hegenberger to 98th Ave. 1.37 14,830 98th Ave to Dutton 1.06 11,180

Signalized Street Service Volume Table
Two-Lane Streets Four-Lane Streets K Factor D Factor LOS C LOS D LOS E Posted Speed = 30 mi/h 0.09 0.55 5,900 15,400 19,900 11,300 31,400 37,900 0.60 5,400 14,100 18,300 10,300 28,800 34,800 0.10 5,300 13,800 17,900 10,100 28,200 34,100 4,800 12,700 16,400 9,300 25,900 31,300 0.11 12,600 16,300 9,200 25,700 31,000 4,400 11,500 14,900 8,400 23,500 28,400 Posted Speed = 45 mi/h 18,600 21,400 37,200 9,400 17,100 19,600 16,800 19,300 33,500 8,500 17,700 30,700 15,300 17,500 30,500 7,700 14,000 16,100 27,900

Service Volume Tables Backing
Service Volume Tables are backed by a long list of assumptions: General assumptions for urban street table: Coordinated, semi-actuated traffic signals; arrival type 4; 120-s cycle time; protected left-turn phases; 0.45 weighted average g/C ratio; Exclusive left-turn lanes with adequate queue storage provided at traffic signals; no exclusive right-turn lanes provided; no restrictive median; 2-mi facility length; 10% of traffic turns left and 10% turns right at each traffic signal; Peak hour factor = 0.92; and base saturation flow rate = 1,900 pc/h/ln. For 30-mi/h facilities: signal spacing = 1,050 ft and 20 access points/mi. For 45-mi/h facilities: signal spacing = 1,500 ft and 10 access points/mi. (Adapted from Exhibit 10-8, 2010 HCM)

Signal Street Serv. Vols
Level of Service 30 mi/h Street 45 mi/h Street LOS A-C < 270 veh/h/ln < 510 veh/h/ln LOS D veh/h/ln veh/h/ln LOS E veh/h/ln veh/h/ln LOS F > 900 veh/h/ln Entries are Peak Direction, Peak Hour volumes averaged across through lanes in peak direction A two lane street (one lane each direction) may be able to carry About 10% more volume before going from LOS E to F.

Service Volume Screening
Street Limits AADT Before BRT After BRT Further Analysis ? Lanes Max LOS D Telegraph Ave. Dwight to Woolsey 16,570 4 28,200 2 13,800 Yes Telegraph Ave Woolsey to SR 24 18,340 SR 24 to 45th St. 16,540 5 3 45th St. to Broadway 16,230 International Bl. Lake Merritt to 23rd Ave 10,220 No 23rd Ave to 35th Ave. 13,370 35th Ave to High St. 15,910 High St. to Hegenberger 13,560 Hegenberger to 98th Ave. 14,830 98th Ave to Dutton 11,180

Posted Speed Limit (mi/h)
For Further Analysis 6 out of 10 supersections selected for further analysis. For rest of case study will focus on one supersection. Street Limits Length (mi) AADT Posted Speed Limit (mi/h) Before BRT After BRT Lanes Max LOS D Telegraph Ave SR 24 to 45th St. 0.60 16,540 30 5 28,200 3 13,800

Comments? Example Problem III.1 – Urban Street Screening Analysis

Example III.2 – Screening for V/C Hot Spots
Objective: To identify future auto v/c hot spots for further analysis. Approach: Step 1: Obtain data Step 2: Compute critical lane volumes Step 3: Interpretation of results V/C hot spots usually at signalized intersections Can be other major intersections.

Sum Up Critical lane Vols
Convert all turn moves to equivalent per lane volumes Find Maximum North-South street critical lane volume NB Left + SB Thru SB Left + NB Thru Find Maximum East-West street critical lane volume EB Left + WB Thru WB Left + EB Thru Sum up maximum critical lane volumes Compare to 1500 If sum of critical lane volumes > 1500, further analysis…

Critical Lane Analysis
N/S Street E/W Street NBL+ SBT SBL + NBT Max N/S EBL+ WBT WBL+ EBT Max E/W Critical Sum Is it <1500? Telegraph 45th St 509 715 252 290 1005 OK 48th St 505 668 55 723 49th St 611 932 123 1055 51st St 636 1018 710 466 709.5 1728 Not OK Claremont 794 582 160 136 954 55th St 914 920 425 1345

Interpretation Critical lane analysis overlooks a lot of subtleties.
Left turn protection is treated same as permitted Heavy truck volumes, narrow lanes, parking interference Pedestrian crossing constraints ignored. It tells you where there may be problems, but not if there are problems. It may miss non-standard problems. For rest of Case Study will focus on the one intersection that failed the critical lane check: Telegraph and 51st St.

Comments? Example Problem III.2 – Intersection Screening Analysis

Example III.3 – Intersection V/C
Objective: To forecast intersection volume/capacity ratios. Taking into account more factors than critical lane. Approach: Step 1: Required data Step 2: Determine left turn phasing Step 3: Convert turns to pce’s Step 4: Assign volumes to lane groups Step 5: Calculate critical lane group volumes Step 6: Compute intersection v/c

Intersection V/C Input
Signalized Intersection Planning Method, Input Worksheet (Part 1) Telegraph Avenue and 51st Street NB SB EB WB LT TH RT Volume 83 794 59 283 505 22 294 763 80 91 582 111 Lanes 1 2 PHF 0.92 % HV 0.05 Parking activity Yes Ped activity Med LT phasing Protected

Intersection V/C Output
Signalized Intersection Planning Method, Calculations (Part 1) Telegraph Avenue and 51st Street NB SB EB WB LT TH RT Step 1. Determine LT phasing Check #1 LT<200 LT>200 Check #2 Not exceed a given Threshold Exceed a given Threshold Not Exceed a given Threshold Check #3 1 LT lane 2 LT lanes LT phasing Protected Step 2. Convert turning movements to passenger car equivalents EHVadj 1.05 EPHF 1.09 ELT ERT 1.3 EP 1.2 ELU 1.03 vadj 95 909 105 324 607 39 347 917 143 104 699 198 Step 3. Assign volumes to lane groups vi (pc/h/ln) 1014 646 174 530 449 Step 4. Calculate critical lane groups vcEW vcNS vcNS=1338 vcEW=634 vc 1972 Step 5. Intersection volume-to-capacity ratio vc/ci 1.20 (Use Default ci=1650 pc/h/ln) Intersection sufficiency Over Capacity

Comments? Example Problem III.3 – Intersection V/C Analysis

Example III.4 – estimate Speeds for Auto and BRT
Objective: To predict auto and BRT speeds Approach: Step 1: Estimate midblock free-flow speeds Step 2: Estimate intersection delays Step 3: Check for mid-block delays Step 4: Compute segment speed Step 5: Estimate BRT speed Step 6: Aggregate to facility level

Estimate Auto Speed 𝑇 𝑖 = 3600 𝐿 𝑖 𝐹𝐹𝑆 + 𝑑 𝑖𝑛𝑡 + 𝑑 𝑚𝑏
𝑇 𝑖 = 𝐿 𝑖 𝐹𝐹𝑆 + 𝑑 𝑖𝑛𝑡 + 𝑑 𝑚𝑏 𝑆 𝑖 = 𝐿 𝑖 𝑇 𝑖 Where: Ti = travel time segment “I” Li = length of segment Dint = delay at intersection Dmb = mid-block delay Si = average speed segment “I” Auto speed = 7.4 mph LOS = F

Estimate Bus Speed 𝑇 𝑖,𝑏𝑢𝑠 = 5,280 𝐹𝐹𝑆 3,600 𝐿 𝑖 + 𝑑 𝑖𝑛𝑡,𝑏𝑢𝑠 + 𝑑 𝑚𝑏 + 𝑑 𝑏𝑠 where Ti,bus = base bus travel time for segment i (s), FFS = midblock free-flow speed from Equation H-1 (mi/h), 5,280 = number of feet per mile, 3,600 = number of seconds per hour, Li = Length of segment i (ft), dint,bus = average bus traffic signal delay not part of dwell time (s), dmb = midblock bottleneck delay (if any) (s), and dbs = total bus stop delay in the segment (s). Bus Speed = 20.3 mph At frequency = 4/hr, LOS = A-C

Comments? Example Problem III.4 – Auto and Bus Speed Analysis

Example III.5 – Estimation of Queues
Objective: To forecast queuing problems on street. Approach: 𝑄𝑢𝑒𝑢𝑒= 𝐴𝑣𝑒𝐷𝑒𝑙𝑎𝑦∗𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 3600 Signalized Intersection Planning Method - Queue Calculations NB SB EB WB LT TH RT Capacity (veh/h) 269 839 95 443 Ave Delay (s) 47 33 52 28 57 46 Ave Queue (veh) 4 8 7 2 6

Comments? Example Problem III.5 – Urban Street Queue Analysis

Example III.6 – Predict Reliability
Objective: To forecast reliability for urban street. Approach: Step 1: Data requirements Step 2: Identify segment types Step 3: Identify demand variability Step 4: Identify weather events Step 5: Identify incidents Step 6: Identify work zones Step 7: Define reliability analysis scenarios Step 8: Compute hourly travel times Step 9: Compute reliability statistics Step 10: Interpret results

Different Scenarios During PM Peak Hour
Reliability Results Different Scenarios During PM Peak Hour Probability Speed (mph) Congested with rain and work zone 0.18% 5.9 Congested with rain, incident, work zone 0.00% Congested with work zone 0.27% 6.0 Congested with incident and work zone Congested with rain and incident 0.40% Congested with incident 0.60% 6.2 Non-congested with rain and work zone 0.01% 14.0 Non-congested with rain, incident, work zone Non-congested with rain and incident 0.02% 14.2 Non-congested with work zone 0.03% 14.7 Non-congested with incident and work zone Non-congested with incident 0.07% 14.9 Non-congested with rain 38.27% 15.0 No Congestion, No Rain, No Incident, No Work Zone 60.14% 15.8 Weekday PM Peak Hours of the Year 95% TTI = 2.34

Comments? Example Problem III.6 – Urban Street Reliability Analysis

Example III.7 – transit, Bike, Ped LOS
Objective: To forecast transit, bike, ped LOS. Procedure: Step 1: Data requirements Step 2: Compute transit LOS Step 3: Compute bicycle LOS Step 4: Compute pedestrian LOS In Progress

Comments So Far? Case Study #3 – BRT Planning What do you like so far?
What do you dislike? What is missing?

Case Study #4 – System Monitoring
14:45

Case 4 – System Monitoring
State produces annual report on state highway system performance. Over 12,000 center-line miles, 28,000 directional segments Three different monitoring station types Some collect AADT only (e.g. HPMS) Some collect Hourly speed data only (e.g. INRIX) Some collect simultaneous hourly spot speeds and volumes (loop detectors)

Case 4 – Example Problems
For All System Performance Monitoring Sites Example IV.1 – Estimate Site Capacities & Free-Flow Speeds For Volume Only Monitoring Sites Example IV.2– Estimate Site Speeds from Volumes For Travel Time Only Monitoring Sites Example IV.3 – Estimate Site Volumes from Speeds For All Performance Monitoring Systems Example IV.4 – HCM Assisted QA/Quality Control Example IV.5– Computation of Modal Performance Measures

Example Problem IV.1 – Site Capacities and FFS
Objective: Need monitoring site capacities and free-flow speeds to compute various performance measures. Approach: Use same method as used in areawide studies to develop capacity and free-flow speed look up tables by facility type and area type.

Capacity and FFS table Facility Type Area Type Free-Flow Speed (mph)
Capacity (veh/ln) Freeway Downtown 55 1800 Urban 60 Suburban 65 1900 Rural 70 Arterial 25 700 35 45 600 Rural Multi-Lane 1700 Rural 2-Lane 1300 Collector 30 1500

Example IV.2 – Estimate Speeds from Volumes
Objective: To estimate speeds for sites that collect only volume data. Approach: Use Akcelik equation to compute speed from v/c ratio and free-flow speed.

input Site ID Length (mi) Lanes AADT K D Facility Type Area Type
Pk Hr (veh/h) PkDir (veh/h) A001 0.85 8 175,800 0.085 0.55 Freeway Urban 14,940 8,220 A002 0.21 6 34,500 0.092 Arterial 3,170 1,740 A003 1.34 4 22,700 0.094 Collector 2,130 1,170 A004 2.50 53,400 0.095 Rural 5,070 2,790 A005 4.50 28,200 0.096 Highway 2,710 1,490 A006 7.30 2 4,600 0.098 450 250

Estimated Speeds Site ID Length (mi) Type Free Spd (mi/h) Cap/Ln J Cap
v/c Spd (mi/h) A001 0.85 Frwy-Urb 60 1800 8.40E-06 7,200 1.14 10.0 A002 0.21 Art-Urb 35 700 9.34E-06 2,100 0.83 18.7 A003 1.34 Coll-Urb 30 600 1,200 0.98 26.2 A004 2.50 Frwy-Rural 70 1900 1.99E-05 3,800 0.73 68.7 A005 4.50 Hwy-Rural 55 1700 3,400 0.44 51.5 A006 7.30 Coll-Rural 45 1300 2.31E-05 1,300 0.19 44.8

Comments? Example Problem IV.2 – Estimating Speeds from Count Data

Example IV.3 – estimate Volumes from Speeds
Objective: To estimate volumes to associate with measured speeds. Approach: Back solve Akcelik equation to determine volumes from measured speeds. Where: x = the link demand/capacity ratio; A= composite variable defined at left. B = composite variable defined at left. T = link travel time (h), To = link travel time at free-flow link speed (h), H = the expected duration of the demand (typically one hour) (h); L= the link length (mi). J = the calibration parameter

Input Speed Monitor Data
Site ID Length Lanes Spd (mi/h) Facility Type Area Type K D A001 0.85 8 10.0 Freeway Urban 0.085 0.55 A002 0.21 6 18.7 Arterial 0.092 A003 1.34 4 26.2 Collector 0.094 A004 2.50 68.7 Rural 0.095 A005 4.50 51.5 Highway 0.096 A006 7.30 2 44.8 0.098

Estimated Volumes Site ID Length Type Free Spd Cap/Ln J Cap A B v/c
0.85 Frwy-Urb 60 1800 8.40E-06 7,200 9.71E-05 1.14 A002 0.21 Arterial-Urb 35 700 9.34E-06 2,100 1.59E-05 6.59E-06 0.83 A003 1.34 Collector-Urb 30 600 1,200 2.68E-04 0.98 A004 2.50 Frwy-Rural 70 1900 1.99E-05 3,800 1.99E-03 0.73 A005 4.50 Hiwy-Rural 55 1700 3,400 3.03E-03 0.44 A006 7.30 Collect-Rural 45 1300 2.31E-05 1,300 1.97E-02 0.19 Site ID Length Type v/c Pk Dir Pk Hr (2wy) AADT A001 0.85 Freeway-Urban 1.14 8,220 14,950 175,900 A002 0.21 Arterial-Urban 0.83 1,740 3,160 34,300 A003 1.34 Collector-Urban 0.98 1,170 2,130 22,700 A004 2.50 Freeway-Rural 0.73 2,790 5,070 53,400 A005 4.50 Highway-Rural 0.44 1,490 2,710 28,200 A006 7.30 Collector-Rural 0.19 250 450 4,600

Comments? Example Problem IV.3 – Estimating Volumes from Speed Data

Example IV.4 – HCM assisted QA/QC
Objective: To error check monitoring data for aberrations Approach: Step 1: compare volumes to capacity Step 2: compare measured free-flow speeds to HCM Step 3: check consistency of measured speeds and flows against standard speed-flow curves.

Before calibration

After Capacity and Speed Calibration

Comments? Example Problem IV.4 – QA/QC of Speed and Volume Monitoring Data

Example IV.5 – Modal System Performance
Objective: To compute modal system performance measures. Approach : Step 1: Compute Auto, truck VMT and PMT Step 2: Compute % VMT by LOS Step 3: Compute reliability Step 4: Compute vehicle-hours of delay Step 5: Compute vehicle-hours in queue Step 6: Compute v/c Step 7: Compute % system miles by bike LOS Step 8: Compute % system miles by pedestrian LOS

Comments Case Study 4? Case Study #4 – System Monitoring

4. Wrap Up 15:15

Wrap Up What do you like the most about the guide & case studies?
What do you dislike the most about the guide & case studies? What is missing? Will you find it useful? Would you recommend it to others?

Next Steps Next steps: Guide goes to highway capacity committee January 2015 Draft Final goes to panel March 2015. Publication in one year.

Our Thanks to our Hosts Comments Tom Creasey tom.creasey@stantec.com
Rick Dowling

Planning and Preliminary Engineering Guide For Using the Highway Capacity Manual NCHRP 7-22 Workshop.

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Planning and Preliminary Engineering Guide For Using the Highway Capacity Manual NCHRP 7-22 Workshop.

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