1 Lec 10, Ch.4, pp.121-127: Parking studies (objectives) Understand parking planning is an integral part of transportation planningKnow the definition of parking termsLearn the methodology of parking studiesLearn how to find out space requirements for a parking garage
2 What we cover today in class… Why do we need to conduct parking studiesTypes of parking facilitiesDefinition of terms related to parking studiesSteps of parking studiesSteps of analyzing parking data
4 Types of parking facilities On-street parking facilities:Parking bays alongside the curbQuestion: What kind of parking do we have in downtown Provo?Off-street parking facilities:Private vs. PublicSurface lots vs. garagesSelf-parking vs. attendant-parking
5 Definitions of parking terms Space-hourA unit of parking defining the use of a single parking space for a period of 1 hr.Parking volumeThe total number of vehicles that park in a study area during specific length of time (usually a day)Parking accumulationThe number of parked vehicles in a study are at any specified time.Parking loadThe area under the accumulation curve between two specific times. (space-hours)Parking durationThe length of time a vehicle is parked at a parking bay.Parking turnoverThe rate of use of a parking space. Divide the parking volume for a specified period by the number of parking spaces.
6 Four steps of parking studies Inventory of existing parking facilitiesCollection of data on parking accumulation, parking turnover, and parking durationIdentification of parking generatorsCollection of information on parking demand
7 Info included in parking studies Parker characteristics (when, where, why and how many people park)Parking supply characteristics (number, location and cost of spaces, who provides and how spaces are controlled and used)Parking needs for new or existing developments
8 Demand FactorsChanges in population, motor vehicle registrations, and travelChanges in CBD employment, floor space, new economic activity generators and loss of existing generators, competition from outlying areasEconomic factors relating to a specific parking project (competitive price changes, subsidies, development of competitive parking facilities)Change in public transit availability, service and usage, or other changes in CBD accessibilityPublic policies regarding parking and transitTechnology or science affecting transportation, new laws and regulations affecting motor travel, energy or fuel shortages, and community and national economic health
9 Inventory of existing parking facilities Type and number of parking spacesTimes of operation and limit on duration of parkingType of ownershipParking feesRestrictions on useOther restrictions (near bus stop, fire hydrant)Probable degree of permanency
10 Collection of parking data Accumulation – checked about every 2-hr basisTurnover and (max permissible) durationNo. of parked carsDemand fluctuates.Time of dayT = (No. of different vehicles parked)/ (No. of parking spaces)
11 Identification of parking generators Spacial distribution, size of parking generators (trip attraction facilities), and available transportation modes affect the level of parking demand.
12 If you get 30% back, you are really fortunate. Parking demand surveyInterview drivers on a typical weekday between 8:00 am and 10:00 pm.Or, give drivers a survey formDestination after parkingTrip purposeTrip originArrival and departureVehicle type
13 Analysis of parking data No. and duration for vehicles legally parkedNo. and duration for vehicles illegally parkedSpace-hours of demand for parkingSupply of parking facilities
14 Parking demand estimation ClassN (= 2 here)Average durationtiNo. of vehiclesniCommuter9 hrs120Shopper2 hrs80D = space vehicle-hours demand for a specific period of time (usually the duration the parking facility is open)N = number of classes of parking duration ranges (commuters, shoppers, business meetings, etc.“Class” means grouping of purpose and parking durations)ti = midparking (meaning “average” here) duration of the i-th class.ni = number of vehicles parked for the i-th duration range (meaning “class”)
15 Parking supply estimation 10hrsj = 1, 2, 3,…Simply stated: S = f*tave/space*MS = practical number of space-hours of supply for a specific period of timeM = number of parking spaces availabletj = total length of time in hours when the j-th space can be legally parked on during the specific periodf = efficiency factor to take into account the time lost during turnovers