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C-1 APPENDIX C Procedures for Internal Capture Surveys This chapter describes a recommended procedural frame- The list of data to be collected for a typical analysis has been work for conducting internal capture data collection at MXD streamlined so that no extraneous data are collected. There are sites. The framework collects the independent variable and numerous types of information that could be interesting internal trip making information required by the estimation descriptors but that do not provide direct relevance to esti- methodology presented in Chapter 3. The audience of this mating internal capture. These extraneous data have been chapter is the potential collector of internal capture data excluded from the data collection plan because requiring them (whether typical traffic consultants, researchers, or public would expand the volume of data to collect (and the cost), agency staff). could intimidate or discourage a potential data collector, and The recommended framework consists of six steps, start- could thereby hinder the collection of the important and rel- ing with the definition of the specific purpose of the data col- evant data. However, the entity conducting the survey may lection effort and concluding with the proper processing of have other reasons to collect additional data. the on-site interview survey data. These steps are described in detail later in this chapter. For the internal capture estimation method presented Need for Quality Assurance earlier in Chapter 3 to be effective, it must be based on con- and Control sistent and correctly applicable data. Therefore, it is essential An important component of the data collection effort is that there be consistency in the definitions used and the means adherence to a quality assurance/quality control (QA/QC) by which internal capture data are collected. The data collec- program. The exact nature of the program should be at the tion framework is structured to be straightforward, easily discretion of the agency that is funding or conducting the data replicated, and adaptable to any potential mixed-use land use collection. However, at a minimum, a QA/QC plan should be and development type. developed at the outset and checks should be undertaken dur- The field data collection can be conducted with an experi- ing each of the six framework steps. enced survey supervisor and low-cost or temporary personnel An important consideration in the QA/QC process should who are given specific training prior to initiation of the sur- be definition of the level of precision desired. This should be vey. The data collection procedure described in Steps 4 and 5 one of the first things determined for each survey. It is critical may at first appear to be onerous. However, all data listed will that the internal capture data be compatible among mixed-use be needed for a typical internal capture trip generation analy- developments. One quality assurance action is to carefully sis. Special or limited studies may require more, less, or differ- digest the definitions and descriptions of both the develop- ent data. Prior to collection of any data the desired outputs ments and the data to be collected and applied. should be examined and the necessary field data determined. Even for such special studies, the recommended framework presented in this chapter will provide a good foundation from Methodology Framework which to work. However, if the resulting data are to be consis- Step 1: Define Purpose of Data Collection tent with other data collected in accordance with NCHRP Project 8-51, the procedures described in this chapter should Step 1 provides the structure and scope for the survey. It is be followed. Any deviations to add more data should not used to identify what is to be collected, how the data are to be change the basic data described herein. used, and where to collect it.

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C-2 Use of Data external conditions, including competing opportunities, modes of access, economic strength of the area; and The first step is to clearly specify the purpose of the inter- willingness of the development(s) owners and/or managers nal capture data collection effort. There are two basic choices: to permit the surveys in a manner needed for the surveys. (1) to study specific land use pairs in MXDs or (2) to determine internal capture rates for a development that is similar to a pro- posed MXD under consideration. In either case, the purpose Timeframe may be to enhance the existing internal trip capture database or to establish internal capture rates for a similar MXD. An important element to establish when defining the data Under both choices, the data to be collected, the survey collection purpose is the timeframe for which internal capture instrument, and the interview procedures remain the same. data are desired or required. Internal capture rates at a mixed- The only difference occurs in Step 2, when a data collection use site may vary by the time-of-day, day of the week, season site is selected. Also important is how those data will be used. of the year. Therefore, select the following: Is it to assess traffic impacts of a proposed development on time-of-day such as the morning peak hour for the site, roads in an area that already experiences congestion during certain periods, or will the data be used in a special generator morning peak hour for the adjacent street, evening peak estimate of trip generation for a regional forecast of daily hour for the site, and evening peak hour for the adjacent travel? The specific use will influence selection of the study street, and other peak hour of generator if it may be subject site as well as the season, day of week, and time-of-day when to traffic impact analysis; surveys should be conducted. day of the week (weekday, Saturday, or Sunday); and season or month of the year (e.g., typical month, holiday shopping season, summer, school-in-session). Site Selection At first glance, it may seem that any MXD could be selected In terms of data that would be useful for the enhancement for data collection. However, mixed-use sites are rarely iden- of the overall internal capture database, refer to Step 2 for tical and often are very different from each other. Their differ- suggested timeframes for particular land use pairs. ences may, in some cases, cause only small changes in internal capture. However, some seemingly minor differences (for Step 2: Select an Appropriate Site example, in the proximity of uses or in an area with a differ- ent nearby land use mix) can cause substantial changes in If the purpose of the data collection effort is to enhance the internal capture. Therefore, it is important to select a develop- existing internal capture database, selection of an appropri- ment that is similar to the one to be analyzed or represented ate mixed-use site should be based on the following criteria. in the resulting database. It is also important to collect the complete set of data to help The site should be of a density and magnitude for which identify differences that could explain the need to interpret the the potential for intra-site walk trips is significant. comparable sites for slightly different characteristics. In other Individual land uses should be totally accessible internally words, although two sites may appear the same, when individ- either by pedestrian pathways or by streets completely ual parameters are examined (e.g., actual walking distance within the development being surveyed (i.e., no vehicular between buildings), slight, yet important, differences may be travel required to make trips between internal points on revealed. streets on or beyond the periphery of the development). Site selection should consider: The mix of land uses should be representative of current or anticipated trends in mixed-use development. types or styles of development that the data will be used to The land uses at the site should interact with each other. analyze; If one component of the mixed-use site does not have development land uses and mix; definitive synergy with any other on-site use (i.e., the num- size range of development; ber of on-site trips to or from that land use are miniscule development maturity (is it fully occupied and sufficiently or unlikely), the overall mixed-use site should be rejected vibrant?) because it really does not act like a true mixed-use site. external conditions; Table C-1 shows the land use pairs the researchers con- representativeness of the development in relation to sites cluded are best suited to both produce significant inter- the data will support analysis of; nal trip capture based on data reviewed to date and exist

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C-3 Table C-1. Priority land use pairs for data collection. Land Use Land Use Retail - Retail - Other Restaurant Office Residential Hotel Entertainment Convenience Retail (Convenience) Retail (other) Restaurant Office Residential Hotel Entertainment in significant quantity in current and anticipated MXDs. descriptive data for the proposed MXD as if it was the data Trip capture data collection should be prioritized for collection site. these uses. Armed with that information, selection of a similar site may The mix of land uses should be transferable. If a particular be possible. Identify a mixed-use site (1) with the same land mixed-use site has a truly unique land use or tenant or set- uses, (2) a similar balance of land uses, (3) with similar site lay- ting, the internal capture data may not be applicable to out characteristics, (4) that is at least three years old, and (5), if other sites. possible, that is located near enough so that competing oppor- The site should be fully occupied (or nearly so), mature (at tunities are similar. In addition, follow the previous criteria. least three years old), and considered successful locally. When data are to be collected for a similar development, it is The area in which the development is located should also always valuable to verify acceptance of transferability with the be mature and mostly built-out with a pattern of develop- agency that will review and decide whether to accept the results. ment normal for that type of area. Advance concurrence with site selection and procedures usu- Buildings are conveniently accessible to each other, both by ally alleviates the possibility of having to collect data elsewhere. distance and by accessibility. Parking is shared between land uses; the percentage of Step 3: Obtain Permission to Collect Data reserved spaces should be minor. at Study Site The data collection program should be able to isolate the trips to, from, and within the development. After an appropriate MXD site is selected for the data collec- There should be locations where representative samples tion, it will be necessary to obtain the permission from the site of trip making to and from each individual land use can owner or property manager. It is not possible or appropriate to be surveyed. collect the necessary data (especially the on-site interviews of To that end, it is essential that through traffic not com- site visitors, patrons, and workers) without their permission plicate data collection at the site. Ideally, there should be and cooperation. In most cases, the owner or manager will no through traffic. communicate with internal businesses, landlords, etc. In some Where tube traffic counters are to be used, the design of cases, the survey supervisor may need to make direct contact to external access points should be such that mechanical gain full permission. counting techniques will produce accurate vehicle counts A primary objective of property management is to keep (e.g., short driveway throats make it difficult to place property ownership and property tenants content by, if pos- tube counters to work properly), or if not, manual or sible, maintaining the status quo. One means of achieving this video counts should be employed. objective is to prevent the occurrence of any problems for the customers, visitors, workers, etc. of their property tenants. To If the purpose of the data collection effort is to determine that end, the analyst should contact property management by internal capture at a site similar to a proposed MXD, the ana- phone and mail/email, and then meet as necessary to discuss lyst should take a slightly different approach. First, the ana- the purpose and procedures of the data collection effort. lyst must define the proposed MXD in terms of the indepen- During each contact, the analyst should convey an under- dent variables collected in Step 3. In other words, compile the standing of the need (1) to not impede patrons and (2) to not

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C-4 divulge proprietary or sensitive information. An incentive for effort. It should be repeated here and with specific reference property management to cooperate is to offer to include a to the following questions and issues. site-specific question during the interview process (and to offer the opportunity to receive the survey results or a copy of Within the specific MXD, is internal capture to be mea- the study report). If a good working relationship can be sured between selected pairs of buildings or throughout developed, property management can often help tailor the the entire site? intercept sampling procedure for the site and to interpret Specify the timeframe of interest for determining internal the survey results. capture. Plan to collect internal capture data for one or more of the following periods: street peak hour collect for at least one-half hour Step 4: Compile Descriptive Data on before to one-half hour after the known peak hour (i.e., Characteristics of Site for at least two hours total) to make sure the peak hour during the survey is actually covered. Check current ITE After a subject site is selected, all information listed in definition for the complete street peak hour definition Table C-2 needs to be collected and compiled. Most of these to ensure the correct peak hour is selected (the weekday data will quantify the independent variables that have been street peak hour is currently the highest 60 minutes of demonstrated to affect internal capture at the mixed-use site. site plus adjacent street traffic within 7 A.M.9 A.M. and 4 P.M.6 P.M.) (3); peak hour of generator determine the highest morn- Step 5: Collect Internal Trip Capture Data ing or afternoon hour of trip generation from trip gen- The on-site internal trip capture data collection effort must eration counts at the survey site. Survey from 1/2 hour be comprised of at least two components. before the beginning of the peak until 1/2 hour after the end of that peak hour; 1. Counts of people entering and exiting each establishment midday collect from 1 hour after the A.M. street peak where interviews are being conducted. These counts are hour to 1 hour before the P.M. street peak hour unless a used as controls for expanding interview samples (since shorter period has been established with the review complete interviews will not be obtained from every person agency for the resulting analysis; and entering and exiting) to represent all people entering and daily Collect survey data during the active part of the exiting the establishment. 24-hour period (e.g., when businesses are open; between 2. In-person intercept interviews of people as they enter/exit a about 6 A.M. and 10 P.M. for typical residential). Specify the preferred day of the week (weekday, Saturday, building (or significant use within a building) to determine or Sunday), based on the period analyses are to cover. If a the origin/destination, mode and purpose of trips internal weekday, select a typical day of the week for the land uses to the mixed-use site. Other data collection options such to be surveyed. as mail-back questionnaires, employee surveys, and visi- Specify the preferred season of the year (holiday shopping, tor surveys do not obtain all the information required to summer, school-in-session), based on the period analyses understand and accurately quantify internal capture at the are to cover. study site. It is highly recommended that cordon counts of all persons Step 5B: Identify Buildings or Uses at Which by mode entering and exiting the survey site be made during to Collect Internal Capture Data the survey. This will provide information on mode of ingress/ Identify the specific buildings at which to collect internal egress as well as the number of external trips being gener- capture data. This will include all buildings and occupants ated. This also provides the basis for an approximate check or a representative sample of each. Specifics will depend on of expanded interview data. resources available, the site size, the number of land uses to Step 5 is subdivided into eight specific steps/decisions that be surveyed, and agreements with the agency that will need to need to be completed to conduct a successful field survey. accept the survey results. Generally, for a single time period, it is desirable to have at least 50 usable interviews per land use Step 5A: Specify Purpose of Internal Capture (30 minimum). Generally sample sizes of less than 30 are Data Collection avoided to ensure the sample results benefit from the central limit theorem that says the sampling distribution of the means Step 1 in the overall data collection framework requires the will approach that of a normal distribution even if the popu- analyst to define the specific purpose of the data collection lation being sampled is not normally distributed (4).

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C-5 Table C-2. Descriptive data for MXD sites. Data Specific Information Desired Comments Overall Name Record the common name for the overall mixed-use development site Characteristics Development Type Specify whether the site is contained within a single-block, multiple of Site blocks or a district Site Maturity Record the year the site opened. If opened in stages, also specify the date of the latest significant building opening. Primary Tenant(s) Determine the primary tenant (i.e., the tenant that serves as the primary driving force behind the overall site being developed as a mixed-use site); some sites may have more than one major (anchor) tenant. Other Land Uses within Site List the other land uses within the site. Use standard nomenclature. ITE trip generation land use classifications are preferred. Building/Area Names and If the overall site is subdivided into sectors with different names or Addresses building addresses, identify them. Physical Site Plan Obtain a site diagram, sketch, plan, or aerial photo of the site, Characteristics preferably to scale. The diagram should show: of Site overall site layout with building footprints, building entrances and pedestrian pathways, access points from street system, and parking supply. Site Area, Size, and Density Record total site acreage. Record number of development units for each building or area (gross square footage, number of dwelling units); at a minimum, collect dwelling units listed for each ITE trip generation land use category. Identify the developed portions by phase for developments to be expanded (if applicable). Locations and Types of Access Document the overall site access plan for motorists (including delivery and service vehicles), pedestrians (including transit patrons), and bicyclists, including: location of each access point, type of traffic control at or serving each access point (i.e., signalized or unsignalized), and transit stops and station entrances along with existing or planned transit service. Internal Circulation Facilities Locate the internal roadways and driveways used by motorists. Locate the pathways for pedestrians (and describe whether pathways are enclosed, covered, or open-air). Locate the pathways or lanes designated for bicyclists, if any. Location and Quantity of Document the location of single-use or shared parking facilities. Parking Record the quantity of spaces in each facility. Document the type of parking facility (e.g., surface, garage). Assess how much of the development truly shares parking. Record the daily/hourly cost for parking. Characteristics Building Size Quantify the building size in development units such as office building of Individual square footage (GSF), amount of leased retail space (GLA), number of Buildings restaurant or theater seats, or number of residential units. Also obtain within Mixed- the number of stories. Use Site Primary Land Use Identify the primary land use within the building as being either retail, (This restaurant, office, residential, hotel, entertainment, or other. If more information is than 5 percent of the building square footage is occupied by a needed for each secondary use, treat it as a separate land use so internal capture can be individual quantified. For both the primary and secondary land uses in a building building or site, classify them in accordance with ITE Trip Generation Land Use area.) codes (1). List the ground floor uses separately since counts may be needed for each. Space Allocated to Individual Quantify the space allocated to primary and secondary land uses (any Land Uses exceeding 5 percent of the building). Since it may be desired to estimate trip generation for specific land uses, it is suggested that the land uses be disaggregated by the following land use categories (which are more detailed than the seven general land use categories listed above): For retail, subdivide into: Convenience (e.g., grocery, drug store, bank, dry cleaner) Full service Discount Other/specialty Other (continued on next page)

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C-6 Table C-2. (Continued). Data Specific Information Desired Comments Characteristics Space Allocated to Individual For restaurant, subdivide into: of Individual Land Uses Fast-food Buildings Sit-down with no bar within Mixed- Family Use Site Quality (This Sit-down with bar information is Family needed for each Quality individual For office, subdivide into: building or Boutique area.) General Medical (nearly all space is doctor offices and medical related uses that serve patients) For residential, subdivide into: Single-family detached Townhouse Condominium Rental apartments For hotel, subdivide into: High price Mid-price with meeting facilities Mid-price with no meeting facilities Low-price For entertainment, subdivide into: Cinema Other For other, specify the use Building Occupancy Quantify the building occupancy (e.g., occupied office, retail, and apartments, not just leased). In a multi-tenant building, contact the property manager, leasing agent, or owner to obtain occupied space data. Building "Primary Access Determine the main access point. If multiple access points exist, Point" or "Center of Gravity" if designate the "center of gravity" (or "access point") for the building. multiple access points are One characteristic of a mixed-use site that has a significant effect on available internal capture is the proximity of its complimentary uses. To measure this proximity, the trip end points must be defined at a certain level of precision. For some buildings (for example, a multi-story office building), the center of gravity seems obvious (in this example, the building lobby). However, for multi-tenant retail buildings, the definition of center of gravity is much less clear. For the purposes of internal capture data collection and data analysis, the following convention for determining a building center of gravity is used: for an enclosed retail mall with more than one anchor store, use inside entrances for anchor stores. It is important to use the location of the mall-side, not outside, entrance; for an open-air community or neighborhood shopping center or for an enclosed mall with a single anchor store, use the location of the main entrance for primary tenant. The primary tenant could be a grocery store, any other big box or a discount store; for an office building, use the office lobby; for a hotel, use its lobby or registration desk; for a restaurant, use its main customer entrance; for a residential site, use its approximate center of gravity of the ground floor dwelling unit entrances; and for an entertainment facility, use its main lobby. Another possibility is to disaggregate all data to individual building entrances. In that case, no center of gravity needs to be determined. In any case judgment will often need to be used. Three examples of centers of gravity include: midway between two entrances on the same building face if both have similar levels of inbound and outbound volumes; center of block face with numerous entrances; and center of block for a land use covering an entire block with entrances on each side, each with similar volumes.

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C-7 Table C-2. (Continued). Data Specific Information Desired Comments Building Proximity Measure proximity of the building to each other building in the mixed- use site. Measure as walking distance along pedestrian facilities between building "centers of gravity" (as defined previously). The desired level of precision for each of the above measurements is 10 percent of the approximate total distance or 100 ft, whichever is less. Connectivity between Buildings Rate the connectivity between the building and each other building in (Not currently part of the mixed-use site, using the following scale: recommended procedure, but a fully-integrated uses the pedestrian connection between uses is consideration in evaluating direct and internal to the development, and does not require internal connectivity) crossing a parking facility at-grade; outside sidewalks with at-grade, priority street crossings pedestrians use street sidewalks. Any street crossings (whether midblock or at intersections) assign priority to pedestrians; and informal the pedestrian connection requires walking through parking aisles or along streets without sidewalks. Parking Supply Rate the parking supply within 600 ft of the building entrance for building tenants and visitors, in particular its convenience. Rate as either ample or limited (based on availability of parking at the ITE Parking Generation report rates) (2). Report total parking spaces and rates if any. Indicate number of spaces reserved for each land use and any time restrictions. Setting/Context Location within Urban Area Classify location of the overall site as either rural, suburban, urban, of Site within midtown/activity center, urban core, or special district Surrounding External Competition for Consider the degree to which off-site land uses will compete with those Region1 Individual Components of Site on-site and assess if that will affect how representative the candidate (Not currently part of site will be to the survey. A development with extreme off-site recommended procedure, but competition may have fewer internal trips than one with almost no may influence internal capture) competition. Selected data collection sites should be representative of typical conditions or of a similar proposed development to be analyzed. 1 Quantification of the site setting and context measures is facilitated if a GIS linkage is provided for the mixed-use site. Step 5C: Identify Intercept Locations at Study Sites be made, but these must be counted (person trips by mode) instead. This is because all trips directly between on-site build- Identify all means/routes of entering or exiting the building ings and the external transportation system are (1) external, (or significant use within the building) whether to make an (2) can be added to trip interview data from that building, and internal or external trip. Identify the entrances/exits that can (3) can be counted as person trips by mode. Usually this con- be used to make a trip internal to the mixed-use site, whether dition only occurs when a garage has access directly to an exter- by foot, bike, or vehicle. At each of these latter entrances/exits, nal street. Pedestrian access does not assure that the person is select an interview location. actually going external unless it is a direct connection to a tran- It is not necessary to interview at external site access points sit station or an off-site garage. Table C-3 provides guidance on where only external trips from specific single-use buildings can where to conduct surveys. Table C-3. Survey and count requirements for several sample locations. Survey Site Location Survey and Count Requirements Survey at either end of each walkway Office building connected to a retail building connecting the office and retail uses. by walkways at several levels in a fully- Count (1) each walkway connecting office and integrated mixed-use site; office building has retail and (2) people entering/leaving the office elevator/stairs to parking garage building via the garage or any other entrance. Stand-alone office building situated near or Survey everyone who passes through lobby or adjacent to a retail shopping center; parking who uses garage (because a person could drive provided on surface and below-grade (accessed to the adjacent retail site and thus would be via elevator or stairs in office building); considered an internal trip). pathway to retail leads to/from building lobby Count at lobby and garage entrances. Survey at the mall entrances Regional mall with nearby office and Count each mall entrance separately (including residential uses any outside entrances for anchor stores).

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C-8 Step 5D: Identify Count Locations at Study Sites The survey supervisor should determine how many survey- ors are needed, based on the survey location requirements The data collection program must include a count of all described in Step 5D and on the minimum sample require- people (not simply vehicles) entering or exiting the building ments described previously. If there is a steady stream of pedes- at which interviews are being conducted. Therefore, appro- trians at a survey location, a rate of 20 complete interviews per priate count locations must be identified. These will usually hour is a reasonable expectation for each surveyor. For less be doors to the property being surveyed (count people enter- active locations, estimate 5 to 10 complete interviews per hour ing and existing), garage access points (count vehicles and for well-trained interviewers who are experienced at approach- occupants); there may be other access points. ing strangers. When estimating manpower requirements, it is The count should keep track of entering and exiting peo- important to assess the pedestrian traffic flow to be intercepted. ple separately. The counts will be used for two purposes: 1. person trip generation count for establishment being sur- Step 5F: Develop Survey Instrument and veyed and Other Data Collection Forms 2. for computing an expansion factor to be applied to the Interviews of persons are typically conducted as they leave interview data. a single land use or building within the site. Each interview Separate data are necessary for survey factoring and for can obtain information on both the trips to and from the sur- determining an overall internal capture rates for the surveyed veyed building and to and from the overall mixed-use site. site. Table C-3 provides guidance on the extent of a count Figure C-1 provides a sample list of interview questions. The program for sample mixed-use sites. questions are written for exit interviews at building or garage The survey should include interviews at as many establish- access points (i.e., interviews of people as they leave a loca- ments as possible while obtaining the desired number of inter- tion). If the interview is to be conducted as people enter the views per land use during each survey period. Interviewers location, the form shown in Figure C-2 should be used. In should be deployed to representative establishments within general, interviews should be conducted in both directions. each land use. Under the best scenario, interviews will be con- However, if that is impossible, complete interviews con- ducted at each establishment. If that is not possible, conduct ducted in one direction can yield usable data since informa- interviews at a representative cross-section within each land tion is asked in each interview for one outbound and one use. When using the sampling approach, deploy interviewers inbound trip. to the busiest locations in each land use. If interviewers are If the survey will be conducted at the cordon driveway or assigned to low volume access points, they will not complete other type of location, the supervisor may need to revise the many interviews. This may be partially offset by having inter- questions to capture the last (for exit interviews) or first (for viewers intercept people at multiple adjacent establishments. inbound interviews) on-site stop. Other modifications may be A competent interviewer (actively approaches people to get needed for special locations or applications. The survey super- interviews, responses are complete and accurately recorded) visor should make sure that the questionnaires to be used fit located at a moderately active entrance should be able to com- the conditions as well as collect the desired data. In general, use plete interviews with at least 10 people per hour. However, of questionnaires such as those shown in Figures C-1 and C-2 activity levels will vary and typically result in a range of 5 to 20 will be adaptable to nearly any standard survey and can be completed interviews per hour. An average interviewer should automated if desired. Each item is needed for a complete analy- be able to obtain completed interviews from one out of every sis or for checking responses. However, some survey sites may three to four persons approached. Recognize that some inter- need supplemental questions to firmly and clearly establish the view candidates will decline to participate or have been inter- characteristics of the trips being reported. viewed previously and not want to participate again. The field survey form should include a space for the inter- viewer to record the date, the name of the development, the interviewer's location within the site, the time each interview Step 5E: Determine Staffing Requirements begins, as well as the interviewer's name. It is important that For mixed-use sites, it is desired to conduct 50 or more every single item be filled out completely and accurately for interviews per land use per survey time period. This may not each interview. Omissions can make an interview unusable. be possible for land uses that are small or are relatively in- Inaccurate entries, guesses, or incomplete entries will also active during the survey time period (e.g., weekday morning invalidate an interview, wasting both time and money. retail). One way an interview sample can be expanded is by Interviews will be completed for a sample of all persons conducting interviews during the same time periods over exiting establishments or the site. Factoring will be used to multiple days. expand the survey data to represent the universe of trips

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As persons DEPART intercept as they leave a specific entrance Interviewer name:__________________________ Building: ___________________ Date: ____________ Start Time: ________ A.M. P.M. 1 Hello. May I please have a moment of your time to ask you a couple of questions for a Mockingbird Station survey? Building Entrance Time Where are you headed now? How are Where did you come from How did What time How did you initially you going immediately before you came to you travel did you travel to (name the to get [name place being exited] from there? arrive here study site) today? there? on that trip? 1. Within 1. Office 1. Auto driver 1. Within (name 1. Office 1. Auto driver 0. I live here If not as driver, (name 2. Retail 2. Auto study site) 2. Retail 2. Auto 1. Auto driver did you have study 3. Restaurant passenger 2. Outside 3. Restaurant passenger 2. Auto an auto site) 4. Residential 3. Walk (name study 4. Residential 3. Walk passenger available for 2. Outside 5. Medical office 4. Rail site) 5. Medical office 4. Rail 3. Bus your trip here? (name 6. Cinema 5. Bus 6. Cinema 5. Bus 4. Rail study 7. Hotel/motel 6. Bicycle 7. Hotel/motel 6. Bicycle 5. Walk site) 8. Other (specify) 8. Other (specify) 6. Bicycle 1. Yes Specify business/building Specify business/building 2. No am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm 2 3 4 5 6 7 8 9 10 11 12 13 14 Figure C-1. Sample exit interview questionnaire.

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Intercept persons as they look like they will ENTER a specific entrance Building entrance: _______________ Interviewer name:__________________________ Date: ____________ 1 2 Time Are you headed Where are you coming from? How did you Before you were at (prior About what How did How did you initially into (name of travel to get place) where were you time did you travel travel to (name survey establishment here? before then? (Immediately you arrive to get site) today? where you are prior to last place) there? there? interviewing) 3. Yes 1. Within 9. Office 7. Auto driver 3. Within (name 9. Office 1. Auto driver 7. I live here If not as 4. No (name 10. Retail 8. Auto survey site) 10. Retail 2. Auto 8. Auto driver driver, did survey 11. Restaurant passenger 4. Outside 11. Restaurant passenger 9. Auto you have an site) 12. Residential 9. Walk (name survey 12. Residential 3. Walk passenger auto (If "no," terminate 2. Outside 13. Medical office 10. Rail site) 13. Medical office 4. Rail 10. Bus available for interview) (name 14. Cinema 11. Bus 14. Cinema 5. Bus 11. Rail your trip survey 15. hotel/motel 12. Bicycle 15. Hotel/motel 6. Bicycle 12. Walk here? site) 16. Other (specify) 16. Other (specify) 13. Bicycle 3. Yes Specify business/building Specify business/building 4. No am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm am pm 3 4 5 6 7 8 9 10 11 12 13 14 15 Figure C-2. Sample inbound interview questionnaire.

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C-11 Location: __________________ Counter: _____________________ Date: ____________ Hour Starting ____:00 am pm 1 2 Minutes Business/Place after Direction hour 3 3 3 3 3 3 3 3 :00 to :15 In Out :15 to :30 In Out :30 to :45 In Out :45 to :00 In Out 4 5 6 6 6 6 6 6 6 6 Figure C-3. Sample door count form. represented in the survey. Counts of all persons exiting the will conduct interviews. Generally the most outgoing and survey locations (or all locations) will be needed to develop the assertive staff will make the best interviewers. Retiring person- expansion factors. This expansion process will need to be alities should not be deployed as interviewers but may make developed as part of the survey design so the proper counts good counters. can be made. Figure C-3 shows a manual count form that can The interviewers should be made familiar with the survey be used to count people exiting (or entering) each door of each instrument through practice of intercept interviews. The same establishment where interviews are to be conducted or that the is true for counters. All survey personnel should be provided interviews are to represent. This form or an automated equiv- with maps showing each location where counts and/or inter- alent can be modified to meet specific survey site needs. views are to be performed. The survey supervisor should Cordon counts may also be needed for factoring and/or include on each map the overall MXD site with names of checking total external trips. These counts should be direc- buildings, tenants, and areas to which interviewees might refer tional and by travel mode. Vehicle occupancies should be as well as the specific location and movements the counter or counted since the recommended estimation methodology interviewer is to handle. (and therefore survey methodology) is for person trips. Field surveys are not trivial. They require thorough prepa- Counts should cover all access points. Figure C-4 shows a ration and training as well as good supervision. Most surveys manual cordon count form that can be used for this type of of this type will require one supervisor for each 10 to 15 inter- survey. This form can be automated or modified as needed viewers and counters. Specifics of the survey site, including for specific survey conditions. size and distribution of survey personnel, may increase or decrease the number of supervisors needed. Step 5G: Recruit and Train Field Personnel Step 5H: Conduct Field Data Collection After recruiting the survey field personnel, the survey super- visor should conduct a training exercise. Some personnel will Inbound and Outbound Door Counts. As noted previ- need to conduct door counts--the counts of people entering ously, total person counts are needed at each location where and existing establishments to be surveyed. Some personnel intercept surveys are to be conducted. If several adjacent

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C-12 Location: __________________ Counter: _____________________ Date: ____________ Hour Starting ____:00 am pm 1 2 Delivery/Service Minutes Personal Vehicles Motorcycles Trucks after Direction Walk Bike Occupants Riders Occupants hour 1 2 3 4+ 1 2 1 2+ :00 to :15 In Out :15 to :30 In Out :30 to :45 In Out :45 to :00 In Out 3 4 5 6 7 8 9 10 11 12 13 14 Figure C-4. Sample cordon count form. establishments are to be surveyed, one counter may be able to vey period actually starts. On the first survey day, the super- count multiple doors concurrently. This will depend on sight visor should walk each counter to the assigned survey location. lines and placement of the counter. A counter should only be The supervisor should make clear what doors and movements assigned those movements to count that can easily be seen are to be counted and where on the form each movement while looking in one direction. Requiring a counter to look in should be recorded (form for each counter should be set up in multiple directions will result in missed persons entering or advance). The supervisor should ask each counter if he or she exiting doors being counted. has any questions to make sure instructions are clear. As mentioned previously, every establishment door where After the survey begins, the supervisor should circulate interviews are conducted must have entering and exiting peo- among the counters to check to see that counts are being ple counted. Counts should be made by 15-minute periods made and recorded correctly. Common problems are line of beginning on the hour or half hour when the survey begins. sight obstructions (unanticipated or resulting because counter Counts should be made for the complete survey period. moved), inattention, recording counts in the wrong column, The survey supervisor should have extra personnel to pro- not keeping track of time, talking to another counter, and vide short breaks for the counters to use restrooms. It is sug- socializing with passersby. gested that breaks be permitted every two hours. With cell phones now in common use, they can be used by survey per- Interviews. The survey supervisor should carefully recruit sonnel to request restroom breaks, if needed before scheduled and select interviewers. The ideal interviewer is outgoing, breaks. Survey personnel should be cautioned to stay hydrated, assertive, willing to approach and talk to strangers, sounds pro- especially on hot days, but not to drink so much that frequent fessional, and understands the purpose and procedure for the trips to restrooms are needed. interviews. The survey supervisor will need to train all survey Counters should be trained in what they are to do. Train- personnel, but spend more time with the interviewers. It is rec- ing should be completed prior to the survey. Training often ommended that each interviewer perform a few practice inter- requires at least four hours and often more. It can be beneficial views under supervision prior to beginning actual surveys. to begin the first day's survey an hour early to make sure the On the first survey day, the supervisor should walk each survey personnel are comfortable with their job before the sur- interviewer to the assigned interview location. The supervisor

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C-13 should make clear what doors and movements for which inter- or half hour when the survey starts. Counts should be made for views are to be conducted and make clear where the inbound the complete survey period. and outbound trips are to be recorded. If appropriate, the The survey supervisor should have extra personnel to pro- supervisor should also discuss the strategy for approaching vide short breaks for the counters to use restrooms. It is sug- people to interview. The supervisor should ask each counter if gested that breaks be permitted every two hours. Cell phones he or she has any questions to make sure instructions are clear. can be used by survey personnel to request restroom breaks, Practice or test interviews are recommended. It may be bene- if needed before scheduled breaks. Survey personnel should ficial to begin interviews an hour early the first shift worked by be cautioned to stay hydrated, especially on hot days, but not each interviewer to make sure the interviewer is comfortable to drink so much that frequent trips to restrooms are needed. and approaching and interviewing people correctly. Counters should be trained in what they are to do. Training After the survey begins, the supervisor should circulate should be completed prior to the survey. On the first survey among the interviewers to check to see that candidate respon- day, the supervisor should walk each counter to the assigned dents are being approached professionally and that interviews survey location. The supervisor should make clear what move- are being conducted and recorded correctly. Common prob- ments are to be counted and where on the form each move- lems include: ment should be recorded (form for each counter should be set up in advance). The supervisor should ask each counter if he shyness in approaching people to interview, or she has any questions to make sure instructions are clear. not asking questions correctly or leading respondents by After the survey begins, the supervisor should circulate among the counters to check to see that counts are being made guessing answers for them, and recorded correctly. Common problems are line of sight incomplete recording of responses, obstructions (unanticipated or resulting because counter not asking all questions, moved), inattention, recording counts in the wrong column, not keeping track of time, not keeping track of time, and socializing with passersby. talking to another survey staff member, and socializing with passersby. Use of Electronic Recording Devices. A number of elec- tronic survey recording devices, including laptop computers, The selection of a representative and sufficient sample of are now available. They can be successfully used for these workers, shoppers, visitors, and residents at the survey site is counts and interviews, if they are set up in formats that are critical to the success of the survey. Therefore, the survey easily used. Formats that do not allow counters or interview- supervisor should closely monitor the real-time progress of ers both ease of use and logical positioning of response only the intercept surveys to make adjustments as necessary to invite confusion and errors. For example, use of an electronic achieve the representative and sufficient sample, keeping in intersection turning movement count board for a door count mind the stated objectives for data collection effort. This may where several doors are to be counted by one person will require redeployment of interviewers to different locations probably not present a logical input format and lead to errors. that have more activity or making other changes that will increase the number of usable interviews for each land use. Step 5I: Supervise in Field Cordon Counts. One counter should be assigned respon- Survey supervisors should have a survey check procedure sibility for each cordon count location. Since the counter must developed as part of the QA/QC procedure suggested at the be able to count not only vehicles, but also vehicle occupants beginning of this chapter. This procedure should be in place as well as pedestrians and bicyclists, the counter will need to be prior to training. The check procedure should include assign- close to where the cordon crossing is located. Ideally the ments of supervisors to check each counter and interviewer counter can be immediately adjacent to the driveway, street, and how to perform the check. Supervisors should observe garage entrance, or other cordon location. In some cases, two interviewers at work and suggest refinements in their approach adjacent cordon locations will be so close together that a single and conduct of interviews. Spot checks of interview records counter can count both with accuracy. In either case, each form should be made early in the first interview period to make sure should be set up specifically for the location(s) to be counted. the responses are both logical and complete. Supervisors A counter should only be assigned those movements to should understand that errors in procedure usually continue count that can easily be seen while looking in one direction. until corrected. If not corrected, interviews for an entire day Requiring a counter to look in multiple directions will result in could be lost as unusable. The same is true for counts. missed persons and vehicles crossing the cordon line. Counts It is important for the supervisors to keep circulating among should be made by 15-minute periods beginning on the hour those being supervised. Even though the counts or interviews

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C-14 are being performed correctly, other supervisory needs may views. Those that are unusable should be deleted. Erroneous arise. Common needs include complaints from business or counts should have been repeated. Small percentages of landlords wanting survey personnel to relocate or stop their unusable interviews should be deleted. Large numbers should survey, unexpected movements that are being missed by the have been repeated. survey, too much activity for one person to cover, "no" activ- ity to count or interview, business opened or closed unexpect- edly, and survey staffer unable to perform as needed. Step 6: Process Internal Capture Data For each survey site (establishment), the analyst should Step 5J: Check Data after Each Period determine the number of usable interviews. Under normal cir- cumstances, 50 or more usable interviews should be available The survey supervisors should perform a check of the for each land use (100 desirable, 30 minimum). In some cases, counts and interviews immediately after each survey period. this will not be possible because the land use will not be active The check should be included in the QA/QC plan, but should (e.g., retail closed during A.M. peak hour) or because the quan- generally include at least the following: tity of development in a land use category will be small. That number can be compared to the total door counts for the same Counts: period. The sampling percentages can be calculated by divid- count covers full period; ing the number of usable interviews by the number of people inbound and outbound balances are logical; counted in the same direction (inbound or outbound). The variations by 15-minute period are logical; same can be performed for each land use by aggregating all modal splits are within the expected ranges; establishments within specific land uses. vehicle occupancies are in expected ranges; Since the interviews represent a sample, the next step is to for cordon counts, it is desirable to total the counts to compute an expansion factor to expand the sample to repre- see if they appear reasonable, particularly the balances sent the total for that universe. This can be accomplished in between inbound and outbound; at least two ways: for door counts, for each land use, compare inbound and outbound totals to make sure the balance appears by land use (normal approach): logical; and separate each interview record into individual trip if discrepancies are found, determine if corrections can be made, and if not, schedule a recount(s) as needed. records; there will be one or two usable trips in each Interviews: interview record depending on how many occurred dur- times of interviews are recorded; ing the survey period; are responses within range of permitted choices (i.e., are aggregate by land use numbers of inbound and out- codes consistent with choices available)? bound trips (aggregate to the interview end of the trip) are write-in responses complete and understandable? reported during the survey period from those inter- destination for outbound trip is logical and mode fits views; this includes both trips reported in the interview origin-destination pair; if they were during the designated survey period (TL for origin of inbound trip is logical for reported time of trip each direction); (i.e., was it really the immediately prior trip?); is time aggregate door counts to the land use level (CL for each reported for that trip logical for immediately prior trip? direction); check response to whether a vehicle was available for determine number of development units (e.g., gross trip; is it logical for reported mode of trip? square feet) covered by interviews and the number of is mode of access to site logical given mode reported for development units for which no interviews were con- these trips? and ducted (in cases where only a portion of establishments where discrepancies or errors appear to exist, review within a given land use were interviewed); calculate a forms with interviewer (call as soon as possible while sample percentage for each land use (S); memory still clearest) to determine if corrections can be the expansion factor (FL) for reported trips for each land made or if interviews must be discarded. If necessary, use and each direction will be: FL = (CL/TL)/S; and repeat interviews where prior interviews had to be dis- apply directional land use expansion factor FL to each carded. trip record; and by establishment: After the survey has been completed in the field, the super- separate each interview record into individual trip visor should complete the checking of all counts and inter- records; there will be one or two usable trips in each

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C-15 Table C-4. Sample summary format--outbound trips. To From Internal External Total Land Use 1 Land Use 2 Land Use 3 Etc. Land use 1 Number or % Number or % Number or % Number or % Number or % 100% Land use 2 100% Land use 3 4 (4%) 8 (8%) 20 (20%) 0 (0%) 68 (68%) 100 (100%) Etc. 100% External 100% interview record depending on how many took place can be created. This should be performed for each end of a during the survey period; trip and in the inbound and outbound directions; that is: aggregate by establishment the numbers of inbound and outbound trips (aggregate to the interview end of the Land Use A outbound trips to internal destinations at trip) reported during the survey period from those inter- each other land use, plus outbound trips to external desti- views; this includes both trips reported in the interview if nations; and they were during the designated survey period (TE for Land Use A inbound trips from internal origins at each each direction); other land use, plus inbound trips from external origins. aggregate by establishment the door counts (CE for each direction); Tables C-4 and C-5 show a format for this summary. Using for each establishment surveyed, compute the expan- the trip records and expansion factors from the survey, sum the sion factor to apply to trips to and from that establish- expanded trips in origin-destination format. This should be a ment; it will be the establishment's directional door straight forward process to begin from the origin end of trips count divided by the establishments usable trips in the and sum to produce a table similar to Table C-4. This provides same direction (CE/TE); a distribution for all trips departing a given land use (the exam- determine number of development units (e.g., gross ple shown is referred to as Land Use 3). Some trips will end in square feet) covered by interviews and the number of the same land use, although at another establishment. Some development units for which no interviews were con- trips will travel to other internal land uses. Some will leave the ducted (in case where only a portion of establishments surveyed development and travel to an external destination. All within a given land use were interviewed); calculate a trips must travel to either an internal or external destination. sample percentage for each land use (SE); For Land Use 3, those outbound trips will total 100 percent. Apply directional establishment expansion factor FL to Hence, each of the entries in the Land Use 3 row can be con- each trip record for each establishment (Ei), then sum to verted to percentages. For example, if there are 100 outbound aggregate trips to the land use level, or trips from Land Use 3 and 8 trips travel to Land Use 2, then FEi = (CEi/TEi)/SE; and 8 percent travel to Land Use 2. Since this is internal, 8 percent those expansion factors are then applied to trip records were internally captured by Land Use 2 (see Table C-5). for each surveyed establishment; the sum equals the ITE has a large trip generation database built from counts total for that land use. of external traffic (vehicle trips) from single-use developments (or at least single classifications). ITE trip generation data After the expansion factors are applied at either the land excludes internal trips. For the Table C-4 data to match the use or establishment levels, a summary of internal capture ITE definition, internal trips must be deleted. Table C-5 shows Table C-5. Sample summary format--outbound trips (ITE definition). To From Internal External Total Land Use 1 Land Use 2 Land Use 3 Etc. Land use 1 Land use 2 100% Land use 3 4 (5%) 8 (10%) 0 (0%) 68 (85%) 80 (100%) Etc. 100% External 100%

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C-16 Table C-6. Sample summary format--inbound trips. To From Internal External Land Use 1 Land Use 2 Land Use 3 Etc. Land use 1 Number or % Land use 2 Number or % Land use 3 Number or % Etc. Number or % External Number or % Total 100% how that is accomplished. Movements between establish- receive a significant percentage of their 56 P.M. trips from ments within the same land use are not considered; they are internal office uses (people going for an early dinner, drinks, or deleted from the trip table. Table C-5 shows the hypothetical hors d'oeuvres). Hence, it would be logical to expect different results with the trips internal to Land Use 3 deleted. The inter- directional percentages between office and restaurant during nal trips to other land uses remain. The total trips external to the P.M. street peak hour. Land Use 3 remain the same as do the external trips, which are the trips of most interest in transportation impact studies. Trips also travel into the surveyed development and its land References uses. A similar summary of inbound trips can be created as 1. Trip Generation, 7th Edition, Vol. 3: User's Guide, Institute of Trans- Table C-6 shows. These numbers and percentages may be dif- portation Engineers, Washington, D.C., 2003, p. ivviii. ferent than the numbers in Table C-4. Logic supports such a 2. Parking Generation, 3rd edition, Institute of Transportation Engi- neers, Washington, D.C., 2004. finding. For example, in a MXD with retail, restaurants, and 3. Trip Generation, Volume 1 of 3: User's Guide, Institute of Transporta- office, the restaurants will send few P.M. street peak hour (e.g., tion Engineers, Washington, D.C., 2008, p. 7. 56 P.M.) trips to office uses because few, if any, office workers 4. Fundamental Research Statistics for the Behavioral Sciences, John T. will travel to their office at that time. However, restaurants may Roscoe; Holt, Rinehart and Winston, Inc., 1969.