Materials developed by K. Watkins, J. LaMondia and C. Brakewood Frequency Determination Unit 5: Staff & Fleet Scheduling

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Service Planning Steps Crew scheduling Vehicle scheduling Timetabling Frequency determination Route design and stop layout Network design

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Agenda Understand the importance of varying route frequencies Discuss different approaches for determining frequencies Calculate demand-based frequencies Displaying variable frequencies in maps and signage

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Frequency Determination … is how often a vehicle will come by any given transit stop on a route … also known as “headways” … is critical to ensuring cost-effective, efficient service

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Frequencies are Variable Vary by route, time of day, day of week, day type

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Many Types of Service Express Bus Priority Service Local Feeder Circular

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Varying Frequencies is Useful It allows us to… Identify important routes Create system hierarchy Improve flow between areas Facilitate rider understanding Support different trip purposes Maintain a cost-effective system

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Why can’t we make every route very frequent?

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Balancing Cost and Frequency It would be great to have fast/ frequent service on every route, but it would result in: – Many buses and drivers – Empty vehicles – High operating costs – Roadway congestion So how do we figure out the best frequency to use?

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Three Main Approaches Policy-based Frequencies – Service meeting fed/state mandates Performance-based frequencies – Service meeting fed/state objectives Demand-based Frequencies – Service meeting ridership needs

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Policy-based Frequencies Often decided by – Experience – Judgment – Simple passenger counts General standards (minutes) – 15 to 20 – peak, high frequency – 20 to 60 – off peak, low frequency

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Policy-based Frequencies Consistent and fixed intervals between vehicles on the route – all day, every day Best in areas with low passenger demand Most likely clock intervals – Repeating at set 10, 15, 20 minutes

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Performance-based Frequencies Fixed to be goal oriented Based on targeted performance standards over a given service day Typically measure non-transit characteristics OR are determined by optimization

Materials developed by K. Watkins, J. LaMondia and C. Brakewood MAP-21 Transit Performance All about optimization!!

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Demand-based Frequencies Most commonly used approach Service provided is directly related to – the number of passengers riding at a given time – the vehicle capacity required to carry them

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Demand-based Frequencies Best in areas where the demand varies throughout the day Meet demand subject to constraints including peak loading, policy headways and productivity

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Demand-based Techniques Three main calculations used to determine this frequency Practitioners do all 3, pick the best Based on – Point Check Counts – Ride Check Counts

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Collecting Point Check Data Team of trained engineers & planners – One at each stop location on the route Usually known busiest route – Decide on set time periods – Record number of riders seen at each stop location – Usually completed several times a year

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Example Stop Number Distance to Next Stop Average Observed Load by Hour Total Passengers 6-7am7-8am8-9am9-10am10-11am 12 mi mi mi mi mi

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 1 (Point Check) Frequency = Volume at the Daily Max Load Point Desired Occupancy Identifies headways that provide the best service to the one stop that is busiest over the entire day

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 1 Data Stop Number Distance to Next Stop Average Observed Load by Hour Total Passengers 6-7am7-8am8-9am9-10am10-11am 12 mi mi mi mi mi

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 1 Frequencies PeriodCalculation Frequency (veh/hr) Headway (minutes) 6-7am400 observed passengers / 50 person capacity am420 observed passengers / 50 person capacity am400 observed passengers / 50 person capacity am320 observed passengers / 50 person capacity am200 observed passengers / 50 person capacity4.015

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 2 (Point Check) Frequency = Volume at the Hourly Max Load Point Desired Vehicle Occupancy Identifies headways that provide the best service to specific stops that are busiest during each time period

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 2 Data Stop Number Distance to Next Stop Average Observed Load by Hour Total Passengers 6-7am7-8am8-9am9-10am10-11am 12 mi mi mi mi mi

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 2 Frequencies PeriodCalculation Frequency (veh/hr) Headway (minutes) 6-7am400 observed passengers / 50 person capacity am510 observed passengers / 50 person capacity am400 observed passengers / 50 person capacity am320 observed passengers / 50 person capacity am220 observed passengers / 50 person capacity4.414

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Collecting Ride Check Data Automatic Passenger Counters (APCs) – Onboard every route – Decide on set time periods – Record number of riders boarding and alighting at each stop location – Tells us load variability across a route – Usually completed several times a year

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Example

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 (Ride Check) Frequency = MAX of… Passenger Load Space (Passenger-km)___ Desired Vehicle Occupancy x Route Length (km) OR Volume at Hourly Max Load Point Vehicle Capacity

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 (Ride Check) Identifies headways that minimize the load variability across an entire route during the busiest time period

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 Data

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 Frequencies For 6-7am: Area in passenger-km: (50*2+100*1+400* *3+32*2.5)=1285 Desired vehicle occupancy: 50 passengers Route Length: 10km Volume at Hourly Max Load Point: 400 passengers (from table before) Vehicle Capacity: 90 passengers (given) Option 1: 1285 / (50*10) = 2.57 Option 2: 400 / 90 = 4.44 Pick the larger: 4.44 vehicles/hour

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 Data

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Class Exercise For 8-9am: refer to diagram Area in passenger-km: Desired vehicle occupancy: Route Length: Volume at Hourly Max Load Point: Vehicle Capacity: Option 1: Option 2: Pick the larger: vehicles/hour

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Method 3 Frequencies Period Frequency (veh/hr) Headway (minutes) 6-7am am am am am3.0720

Materials developed by K. Watkins, J. LaMondia and C. Brakewood So Which Method is Better? Which is more important? Peak day…Method 1 Peak hours…Method 2 Route variability…Method 3

Materials developed by K. Watkins, J. LaMondia and C. Brakewood A Note on Finishing Calculations Headways should always be rounded down to the next minute If clock headways, round to appropriate minute on schedule

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Displaying Frequencies Most transit maps highlight routes Do not designate differences between them Is this a concern?

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Display Concerns Yes! Not all routes are equal It shows us anticipated speeds, wait times, service times Emphasizes network aspect of the transit system

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Displaying routes

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Frequency Map

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Conclusion Routes must vary in frequency. There are 3 main approaches for coming up with these frequencies. Demand-based frequencies rely on capacity and ridership data. Frequencies need to be displayed.

Materials developed by K. Watkins, J. LaMondia and C. Brakewood Reference Materials in this lecture were taken from: Mark Hickman, Fundamentals of Transportation wikibook, “Network Design & Frequency”, _Transportation/Network_Design_and_Frequen cy _Transportation/Network_Design_and_Frequen cy Chapter 8 of the TCRP “Transit Capacity and Quality of Service Manual, 3 rd edition”, 2013.