THE TRAVEL OF PERSONS TO DOWNTOWN BOSTON by ROBERT G. DAVIDSON B.S., M.I.T. (1950) SUBMITTED OF IN THE PARTIAL REQUIREMENTS DEGREE OF CITY at MASSACHUSETTS FULFILIKENT FOR MASTER THE OF PLANNING the INSTITUTE OF TECHNOLOGY June, 1954 Signature of Author Dbpartment of City Planning May 24, 1954 Certified by Thesis Supervisor Accepted by Chairman, Depaxr Nnental Committee on graduate students ABSTRACT THE TRAVEL OF PERSONS TO DOWNTOWN BOSTON Robert G. Davidson Submitted to the Department of City Planning in partial fulfillment of the requirements for the degree of Master of City Planning. In order to advance the position of research in the field of 'the movement of people to Central Business Districts', the general intent of this thesis is to provide necessary basic information in regard to person-travel to Downtown Boston, and to make exploratory use of the information towards learning more about the importance of Downtown Boston and its component parts. The objectives of this study are twofold. The first objective is to determine the number and geographic distribution of person-trips to Downtown Boston on an average day in 1950. The second objective is to examine the relative importance of various non-residential land uses in terms of their person-trip generating power. Each of the objectives has been realized after the The collection and adjustment of much basic information. findings of the first section show that 575,OOO persontrips were made to Downtown Boston on an average day by Of these, 415,ooo were all modes of motorized travel. destined for seven zones comprising the core of Bostonts Downtown Business District. Section two, which relates these person-trips to four major classifications of non-residential uses in the seven zones, finds that the per square foot generating power for large amounts of each of the four use groupings is substantially different. Retail and consumer services accommodations attract more than twice as many persons per square foot as office accommodations. Manufacturing facilities generate about one and one-half as many trips per square foot as do office accommodations. Office facilities, on the other hand, attract more person-trips per square foot than wholesale and storage facilities. The findings also indicate that of the 415,OOO persontrips bound for the seven zone core of Boston's Business District, approximately 45% are bound for retail, consumer services accommodations, and the remainder are equally divided between office facilities on the one hand, and manufacturing and utility facilities, and wholesale and storage facilities on the other hand. The thesis concludes that a relationship between person-trips and land use facilities is a potentially valuable tool for describing, evaluating, and designing Central Business Districts and therefore deserves a great deal of additional study and analysis. TABLE OF CONTENTS Page Introduction Objectives. Lee. I **8 Section I - Amount and Distribution of Travel Objectives Procedure ... Findings Section II - Use, Trip Relationships ... .i.. Table IV - Amount of Accommodations Findings 4 9 10 11 Table II - Amount of Travel Graph I - Amount of Travel Table III- Distribution of Travel Procedure 4 5 .... Table I - Traffic Zone Identification Map I - Traffic Zone Location Objective 2 .g. Graph II - Generating Power *4agnitudes 11 12 13 15 15 15 16 19 20 Conclusions .... 22 Appendix I - Person Travel .e.. 23 Concerning Motor Vehicle Travel 23 Table V - Monthly Variation Table VI- Monthly Variation 24 26 Concerning MTA Travel Table VII - Monthly Variation Concerning Rail Travel Table VIII - Monthly Variation Appendix II - Land Use, Person-Trip Relationships Table IX - Demonstration of Reasonableness Table XI - Demonstration of Reasonableness 27 28 29 29 30 32 33 INTRODUCTION The "Central Business District" is the heart of the Metropolitan Area. It contains those facilities and oper- ations that guide and regulate the daily economic, governs mental, social, and cultural activities of the Metropolis. It also contains, in this day of increasing mobility, a malady of the arteries; a disease that impairs efficient operation of the movement of persons and goods. This mal- ady is commonly labeled "traffic congestion". The future would seem to indicate an even greater mobile civilization. This will magnify circulation problems and as a result will eventually necessitate a more intense evaluation of the future of central business districts. It is believed that research has not played enough of a role in regard to this subject. Study and research have not yet provided a way of adequately identifying the problems. Yet only after the problems are properly recognized and delineated will means be available to allow the making of intelligent decisions upon the future design of the metropolitan core. It is further believed that the failure of research is actually caused by a lack of basic information upon which advance studies must rely. It is the general intent of this thesis to provide some of this required basic information as it relates to Downtown Boston, and in addition, to explore a possible usefullness of the data. Objectives The objectives of this study are twofold. The first objective is to determine the number of trips made by persons to Downtown Boston, and to identify their destination distribution within the Downtown Area. The second objective is to examine the relative importance of various non-residential land uses in terms of their person-trip generating power. The achievement of the first objective, the fact finding or inventory phase, is of course, a prerequisite to undertaking the second objective. It is emphasized, however, that the findings of the first section are expedted to be useful to many studies beyond the reach of this thesis. for the purpose of gresenting Therefore, a more complete description, this material has not been confined to only that required for section two. A reasonably accurate description of the magnitude and distribution of person-trips to Downtown Boston does not, to the author's knowledge, exist in written form. In 1945 a comprehensive origin and destination survey of Metropolitan Boston was conducted by the Massachusetts Department of Public Works. This survey, which included a 5% sample home survey, made use of counting and survey procedures that have had nationwide acceptance. The results of the survey have been published in summary form in the 1948 "Master Highway Plan for Metropolitan Boston". Although the results of 0 & D 2 ACKIN OWLEDGEMENTS The nature of this study has demanded a great deal of contact with many individuals engaged in the field of the transportation of people in the Boston Area. The cooper- ation of these individuals has been outstanding. The mag- nitude of the number of persons in the transportation field who offered help is so great, however, that specific acknow- ledgement is hereby made instead to the agencies the individuals represent: . . . . . . . . . The The The The The The The The The New York, New haven, and Hartford Railroad Company New York Central Railroad Company Boston and Iaine Railroad Company Metropolitan Transit Authority Massachusetts Department of Public Works Boston Public Works Department Boston Traffic Commission Boston City Planning Board many bus companies In addition, the author is most grateful for the aid contributed by Thomas E. McCormick and Sydnor Hodges, Director and Principal Planner, respectively, of the Boston City Planning Board, and Louis B. Wetmore, Professor of City Planning at the Massachusetts Institute of Technology and thesis advisor. survey may have accurately reflected the magnitude of travel at the time of the survey, the fall of 1945, it can be demonstrated that they no longer correctly describe the amount of travel to Downtown Boston during more recent years. The means do exist to recompute the amount of travel, and this, as outlined in section one, has been done. The o & D survey results are, however, the only available sources of information describing the geographic distribution of these trips and accordingly have been relied upon here. The second objective is to determine if various kinds of downtown, non-residential uses do attract different amounts of trips, and if so, by what magnitude. The results of this section are probably of greater interest than those of section one because they are products of previously unexplored relationships; namely, the number of person-trips with an inventory of square feet of floor q ace. The usefulness of this type of relationship is twofold. First, because it is a density relationship, a sense of meaning and scale is attached to information of travel. Just as population can be better visualized in terms of density, so too can travel data be more usefully described. Secondly, and perhaps most importantly, this type of relationship (when fully developed) will have immediate and direct application in the planning and development of central business districts. 3 SECTION I Objective The purpose of this section of the thesis is to determine the number and geographic distribution of person-trips to Downtown Boston. These trips are to be expressed as the number of trips made during an average day in 1950 to the Downtown Boston defined below. An "average day" has no particular identity in reality; it is merely a hypothetical 24 hour period in which travel to the Downtown Area is most typical. It hasbeen selected for use because it is more easily understood, is easier to compute, conveys a more proper meaning, and is susceptible to easy and proper conversion when the need requires. The number of trips are to be expressed as the number of trips made by individuals to or from Downtown Boston, A person traveling from Brighton to Downtown Boston, accomplishing the mission of the trip, and returning to Brighton, would be presented as having made one trip to the Downtown Area. 0 & D surveys, and most other traffic data of a similar nature, usually express such a routine as two trips, and quite appropriately in view of the objectives of a traffic study. The objectives here are basically different as emphasis is on the number of persons. The number of trips, per se, can be established by doubling the amounts shown below. The "Downtown Bostln" that is referred to throughout this study is that area north and east of Massachusetts Avenue bounded by the Charles River, Boston Harbor, Fort 4 Point Channel, and South Bay. This particular area has been selected, as has the base year of 1950, because of the nature of the available information that must be relied upon. This Downtown Area, which contains residential areas as well as non-residential areas, has been sub-divided into smaller zones. This allows the travel data to become more meaningful and provides a way for undertaking the analysis of section two. Procedure The procedure that has been used to determine the number of person-trips to Downtown Boston is a simple one. Informa- tion has been obtained from each agency involved in transporting persons to Dcwntown Boston. Data on travel by motor ve- hicle, which has been the most difficult to obtain, is primarily the result of various surveys conducted by the Massachusetts Department of Public Works and the Boston Traffic Commission. Information of travel by mass transportation facilities has been collected from the MTA, each of the railroads, and the bus companies. All of this information has been evaluated and ad- justed, and the results have been grouped together to give the total number of person-trips to the Downtown Area. The geographic distribution of the person-trips has been determined by using the results of the 1945 0 & D survey. The 0 & D survey, which sub-divided Downtown Boston into seventeen zones, distributed travelers to each zone by each mode of travel. This distribution, on a proportionate basis, has been applied to the recomputed number of person-trips by each mode of travel. 5 The following discussion explains in detail how the findings have been established. discussed separately. Each mode of travel is The manner in which the person-trips have been distributed, geographically, is explained on page 8; the findings on page 11. Concerning the Amount of Travel by Private Motor Vehicle On a Tuesday, Wednesday, and Thursday, of the second week of June, 1950, a cordon count was conducted by the Massachusetts Department of Public Works and the Boston Traffic Commission. Each motor vehicle (trucks, buses, and passenger cars) as it entered and/or left the Downtown Area between 7 a.m. and 12 midnight was counted and recorded. The weather conditions were normal; there was no other apparent abnormal influence to disturb the accuracy of the count. The results of this cordon count have been used as basic data to establish the number of persons making trips to Downtown Boston by private motor vehicle. The immediate objective is to transform figures representing the number of vehicles crossing a cordon line surrounding Downtown Boston to figures representing the number of average daily perz n-trips. This is accomplished by making a series of adjustments to the cordon count results. These adjustments are identified below and described in detail in Appendix I. The 1950 cordon count has been adjusted: , to correct for an improper cordon line location, to expand the time base to a 24 hour period, 6 . to correct for seasonal variation and to determine the average day in the most typical month, . to deduct through traffic, and . to transform vehicle figures to person figures by the application of a persons per vehicle ratio. Concerning the Amount of Travel by MTA The number of persons bound to or from Downtown Boston via MTA has been determined from counts and records obtained from the MTA. On Wednesday, March 22, 1950, the MTA recorded the number of fares collected in all underground and elevated stations during the entire length of the daily service of these facilities. All fares collected in Downtown Boston stations have been tabulated (excluding Massachusetts Station, Symphony Station, and Northampton Station, which are on the fringe of the Downtown Area) and are assumed to represent a proper basis for determing the number of person-trips. March 22, 1950, was a day of normal weather conditions. Easter was far enough removed so as not to cause the count to be abnormal. date is The hockey game at the Boston Garden on this considered as typical of the many events that occur daily. A more detailed description of the adjustments that have been made to this fare count is presented in Appendix I. The adjustments are: , to correct for seasonal and monthly variation and to determine the most typical month, , to add for unrecorded bus and street car trips, and to deduct intra-Downtown Area trips. 7 Concerning the Amount of Travel by Railroad and Bus Information regarding travel by rail has been obtained directly from the New York, New Haven, and Hartford; the New York Central; and the Boston and Maine. The only adjustment that has been made to this data concerns the monthly variation. The details are presented in Appendix I. The bus companies have furnished the necessary information regarding bus travelers. No adjustments have been made because of the relative insignificance of this type of travel. Concerning the Geographic Distribution of Person-trips As previously stated, the 0 & D survey divided Downtown Boston into seventeen zones. The number of persons using each mode of mass transportation and the number of motor vehicles destined for each zone from outside the Downtown Area was established by the survey. From these results, which were presented graphically at a scale of 10,000 trips per inch, the proportion of trips destined for each zone by each mode of travel, expressed as a percent of the total trips by each mode to the entire Downtown Area, has been determined. The person-trips have been distributed by applying these proportions to the total number of persontrips to Downtown Boston by various modes of transportation on an average day in 1950. By using the 1945 data in this way the following assumptions are made: that the quantity, quality, and pattern of land uses did not change enough to cause significant changes in the proportionate generating power of the non-residential and residential zones from 1945 to 1950, and that there was 8 little change in the destination pattern of the users of each mode of travel. The location, and a brief description, of each zone can best be presented in map and table form. Map I shows Table I describes each zone, its size where each zone is; and predominate use. Table I Zone # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 - Showing the Size and Use of Each Zone Size (Acres) 58 98 62 126 68 228 142 152 104 160 160 106 64 73 136 26 66 Predominate Use Non-residential Residential Wholesale, Storage Office Retail Non-residential Residential Residential Residential Mixed Residential Non-residential Park Residential Residential Non-residential Non-residential 9 Remarks North Station Area North End Faneuil Hall Market Banking, Insurance Retail Center S. Sta., Park Sq. South End South End South End Symuphony Hall Area Back Bay Back Bay Public Garden, Common Beacon Hill Beacon Hill, West End Scolley Sq. Canal St. Area ) GEt DOlWNTO(,V/N 305T0N M y a~IO;'~s~v~ -383 OLD$ t[ --- LQ 14044 *O -77 77:-:- CT\ T, FINDINGS Table II - Showing the number of persons destined for (an equal number originate in) Downtown Boston via each and all modes of travel during an average 'day of each month of 1950, Month Pass Car Truck MTA Rail Bus Total Jan. 200,000 31,000 228,000 62,000 10,000 531,000 Feb. 206,000 32,000 232,000 60,000 10,000 540,000 March 222,000 33,000 234,000 57,000 10,000 556,000 April 252,000 39,000 223,000 57,000 10,000 581,000 May 276,000 43,000 222,000 55,000 10,000 606,000 June 288,000 44,000 210,000 54,000 10,000 606,000 July 292,000 45,000 174,000 52,000 10,000 573,000 Aug. 288,000 45,000 187,000 51,000 10,000 581,000 Sept. 262,000 41,000 202,000 53,000 10,000 568,000 Oct. 256,000 40,000 213,000 56,000 10,000 575,000 Nov. 252,000 39,000 222,000 57,000 10,000 580,000 Dec. 238,000 38,000 244,000 57,000 10,000 587,000 Thenumber of persons that enter or leave Downtown Boston on foot and bicycle have not been studied in detail. The findings do not include such travel and are incomplete in this regard. The significant findings include: the proportion of trips made by each mode of travel, to Downtown Boston, the amount of trips and the monthly variation of each mode as well as for the total, It is also important to note that the fall months of October and November are the 11 Graph I - Showing the number of person-trips to Downtown Boston by each and all modes of travel, by months of 1950. 600 '(all modes of travel) I, .0..0 / "b4 low,-- 550J 500 300 I (Passenger car) 00* 0 250 0 V. 200 (NTA) I- IL 150 100 (Rail) 50 ......... Truck ) (Bus) -9-I J F N A M J J A 8 0 1 D Months - 1950 May, RGD 1950 1 3 months during which the average day is most likely to occur. During these months the flow by each mode of travel, and the total travel by all modes, to Downtown Boston is at or near the average level. Therefore the October-November figures will be used in section two. Table III - Showing the number of average daily persontrips destined for (an equal number originate in) each (The figures in the zone by each mode of travel in 1950. total column have been rounded off). Zone # Pass. Oar Truck Bus Rail KTA 4,0 00 Total 300 25,500 200 11,500 300 200 27,000 28,800 16,0 00 1,300 86,500 4,800 71,000 12,5 00 3,300 121, 500 49,500 5,600 33,000 12,5 00 1, 500 102,000 7 8,200 2,600 6,400 300 17, 500 8 6,400 1,600 6,400 300 14, 500 9 6,900 1,200 6,400 300 15,000 10 8,900 1,200 6,400 300 17,000 11 15,600 1,200 3,700 1, 200 200 22,000 12 21,200 2,400 12, 500 5, 000 800 42,000 13 200 14 8,900 700 4,500 15 11,200 1,200 7,300 16 11,700 1,200 7,300 17 7,400 2,400 4,500 1-17 255,OOC 1 13,500 1,400, 6,400 2 6,400 1,300 3,700 3 15,300 5,600 5,400 4 33,000 5,600 5 30,000 6 200 40,000 215,000 13 400 200 15,000 300 20,000 600 300 21,000 1, 200 200 15,500 600 55,000 10,000 575,000 Zones 3,4,5,6,12,16, and 17 are the core of the business area. Within these zones exists the major portion of non-residential uses in Downtown Boston; to within these zones 72.5% of the total Downtown person-trips are destined, These zones and the amount of travel to them have been selected for further analysis in the following section. Other findings of interest and import which are not of direct concern to this thesis can be isolated at this point. It is hoped that some of the information presented will be useful to other advanced studies of the "Central Business District". 14 SECTION II Objective The purpose of section two is to examine the relationship between the amount and type of non-residential uses, and the amount of travel to these uses. The specific ob- jective is to find out if different classifications of nonresidential uses do vary in their person-trip generating power, and if so, by what magnitude. Procedure The procedure has been to relate the findings of section one with the results of an inventory of floor space accommodations. The inventory survey was conducted by the staff of the Boston City Planning Board during the spring of 1953. The results of this inventory, which are expressed in terms of the gross floor area of each type of use for each zone, have been corrected for major changes in accommodations occurring since 1950. They have also been regrouped into four major use classifications so that the following relationships can be accomplished. The four major use classifications are: (a) retail, consumer services, and institutional accommodations, (b) office accommodations, (c) manufacturing and utility accommodations, and (d) wholesale and storage accommodations. As previously stated, the zones to be subjected to this analysis are 3,4,5,6,12,16, and 17, the core of Boston's business district. The amount of each use within each zone, and the number of person-trips to each zone, are summarized in Table IV below. 15 Table IV - Showing the amount of various uses (as prev- iously classified) and the number of person-trips to Downtown Boston, in zones selected zones as of 1950. Accommodations (000's sq. ft.) a R,OS,I b Off. c d MfgUt__WhSt Trips Total 3 475 200 1.100 2,300 4,075 27,000 4 1,180 8,700 2,240 2,880 15,000 87,000 5 6,360 2,810 1,230 540 10,940 122,000 6 4,500 3,000 2,000 2,400 11,900 102,000 12 2,340 3,770 180 230 6,520 42,000 16 660 2,250 320 20 3,250 21,000 17 1,065 90 1,720 1,660 4,535 16,000 The table above shows, upon study, that there is a difference in the magnitude of generating power between uses. For example, the retail zone (zone #5) which contains a smaller amount of total accommodations than the office zone (zone #4) attracts substantially more persons. The question that arises then is, what is the amount of the difference of person-trip generation between types of uses? The answer to this question has been arrived at by relating a series of algebraic equations; one for each zone. The ingredients of each equation are as follows: xR /yO/zM/wW = P x equals the number of person-trips destined for each square foot of retail, consumer services, and institutional use. R equals the number of square feet of each such uses. y equals the number of person-trips destined for each square foot of office use. 0 equals the number of square feet of office use. 16 z equals the number of person-trips destined for each square foot of manufacturing and utility use. M equals the number of square feet of such uses. w equals the number of person-trips destined for square foot of wholesale and storage use. W equals the number of square feet of such uses. P equals the total number of person-trips to these zones. Values for the unknowns in these equations have been determined by, essentially, scving the equations simultaneously. Appendix II contains a more detailed description of how the equations have been solved. This process of solving for generating power values of various types of non-residential uses has certain limitations that require explanation. First and foremost it is to be noted that this analysis deals only with large quantities of space occupied by each type of use. The findings therefore apply only to equal quantities, onehalf million square feet of accommodations of each use or more. The results do not describe the generating power of any one establishment (which is liable to be quite different than the results shown here). The findings of this analysis represent the average generating power of many many establishments. Secondly, it is to be recalled that the person-trip data used in this analysis included only those trips made to (or from) Downtown Boston from (or to) elsewhere. The trips made between one part of Downtown Boston to another are not incuded. In effect the major portion of the motor- ized trips are included; the many walking trips taurants, etc., are not. to res- Therefore, the findings presented 17 below show a substantially lower generating power than would be the case if the intra-area trips were accounted for. This is especially the case regarding retail and consumer services uses which undoubtedly attract the greatest number of intra-area trips. Thirdly, but much less importantly, the simultaneous equating process assumes that all kinds of establishments are generators of inter-downtown trips. is not necessarily true. establishments, This, of course, Many retail and consumer services a restaurant for example, or a bank, prob- ably are not generators of this type of trip at all but generators of only intra-area trips. This analysis would be more accurate if those establishments catering to intraarea trips could be identified and corrected for. This cannot be done and as a result the findings in the case of retail and consumer services show a slightly higher generating power, and in the case of the other uses probably show a slightly lower generating power. 18 Findings The actual results are shown in Chart II on the next page. range. is The generating power of each use is presented as a Somewhere in each range, usually near the middle, the average generating power for the total Downtown Business District accommodations of each type of use classification. The range itself expresses the apparent size of the generating power variation that occurs from one zone to another. The most significant finding is the difference in the person-trip attractiveness between one use and another. Retail and consumer services accommodations attract more than twice as many persons per square foot as office accommodations. Manufacturing facilities generate about one and one-half times as many trips per square foot per day as do office accommodations. Office facilities, on the other hand, attract more person-trips per square foot than wholesale and storage accommodations. Some indication of the relative drawing power of various sections and kinds of uses in Downtown Boston can be gained by reinserting these findings into the equation (as shown in Appendix II). Of the 575,000 person-trips destined for the entire Downtown Area, approximately 415,000 are destined for the seven zones described as the core of the business area. Of the 415,000 person-trips so destined, about 45% are bound for the retail, consumer services, and institutional uses, slightly more than one-quarter are bound for office accommodations, and slightly more than one-quarter are bound 19 Graph - Showing the magnitude of the relative generating II power of various land use classifications in Downtown Boston (as based on a scale of the number of square feet of use per person-trip during an average day in 1950). e (High) 50 Retail Consumer Ser. Institutional 100 Manufacturing (Utilities) Generating Department Stores Specialty St. Furniture St. Garment Power ' 150 Ratio Square Ft. Persons 200 Office Meat 250 and Produce Mkt. (Low) Wholesale Furniture 300 Storage 400 May, RGD 1954 for the remaining manufacturing, utility, wholesaling, and storage facilities. It must be recalled here that the above findings relate the many person-trips to Downtown Boston with the kind of facilities acting as destinations, regardless of trip purpose. Therefore the trips described here as bound for retail facilities (or any other kind of establishment) include all kinds of person-trips, regardless of whether the purpose of the trip is work, business or shopping. 21 CONCLUSIONS The substance of the conclusions of this thesis is to be found in the findings of sections one and two. These findings are offered in the belief that they will contribute some knowledge about Downtown Boston, and in the hope that they will prove valuable to those undertaking necessary advance studies of Downtown Boston and other "Central Business Districts". Equally important, especially from the standpoint of a thesis, is the development of a measurement of the generating power of specified types of non-residential uses. The development of this measurement, expressed here in terms of person-trips per square foot of accommodations, is far from completed in this analysis. In fact this work represents but an introduction to the subject. Further correction and refinement must at least compensate for the limitations mentioned in section two. To accomplish this it will undoubtably be necessary to undertake a complete new survey (most profitably in conjunction with a comprehensive origin and destination survey) rather than utilize the results of past surveys. It is concluded that further development of a measure of generating power can and should take place. When it does take place valuable knowledge can be added to that which now exists about the many characteristics of the "Central Business District". 22 APPENDIX I Concerning the adjustments made to the 1950 cordon count 1. The 1950 cordon line was located on the southwestern side of the intersections of Massachusetts Avenue and the inboundoutbound streets (for example, Beacon Street). Therefore veh- icles entering an intersection from the southwest were counted before crossing Massachusetts Avenue. The possibility of many of these vehicles turning left or right and not entering the Downtown Area was examined. However, investigation of traffic counts made at many of these intersections indicates that approximately as many vehicles pass the northeastern side of these intersections as pass the southwestern. Therefore, no adjustment has been made. 2. The 1950 cordon count also included those vehicles using the Harvard Bridge on the north and Massachusetts Avenue on the south. Because many of these vehicles do not come from, or go to, Downtown Boston, the cordon count has been adjusted accordingly. It has been estimated by the author, after un- recorded observation, and after investigation of two intersection traffic counts, that 60% of those using Harvard Bridge and Massachusetts Avenue at the cordon line are bound to or from the Downtown Area. Therefore, a figure amounting to 40% of the motor vehicles passing these points have been deducted from the total cordon count. This amount (40%) is approxi- mately 4% of the total number of vehicles recorded in the cordon count. 3. The 1950 cordon count was made over a 17 hour period, from 7 a.m. to 12 midnight. 23 Because all the information herein is to be presented as daily flow, the count has been The factor commonly used and generally accepted expanded. by traffic engineers in this area for this particular type of expansion is 1.10. This factor has been used here but has been applied so that the adjusted number of vehicles entering and the number leaving the Downtown Area during a 24 hour period are equal. A factor of 1.08 was applied to entering traffic flow, and a factor of 1.12 was applied to leaving flow. 4. The 1950 count was taken on a Tuesday, Wednesday, and These days of the week are considered by traffic Thursday, engineers as normal and average days. No adjustment has been made to the count in this regard. 5. The cordon count was taken during the middle of June. In terms of the flow of motor vehicles to Downtown Boston, June is not a representative month, and the cordon count has been adjusted accordingly. Extensive search for a basis for mak- ing a proper adjustment has not been very successful. The information that has been obtained is summarized below in Table V. The monthly variation of motor.vehicle flow is des- cribed as the percentage deviation of a given month from the average month. Table V - Month January February March April May June July August September October November December Showing sample monthly variations Sumner Tunnel* a b .82 .81 .75 .82 .88 .89 .97 1.00 1.10 1.09 1.14 1.12 1.14 1.16 1.15 1.14 1.02 1.03 1.03 1.02 .98 .97 .97 .96 24 MDPW** .78 .85 .90 .95 1.00 1.10 1.25 1.35 1.10 1.00 .90 .85 of motor vehicles Route 138*** a b .80 .78 .72 .79 .88 .89 .96 .98 1.13 1.11 1.14 1.16 1.20 1.18 1.18 1.17 1.03 1.05 1.05 1.03 .98 1.00 .91 .90 * These figures were established from Sumner Tunnel collection records for 1950. Column "lal is the result of the actual monthly counts without adjustment. Column "b"' is the result of correcting each month for a varying number of days per month. ** These are figures used by the Massachusetts Department of Public Works for general application to all state highways, *** These figures are the result of a long term traffic count on Route 138 in Milton, Massachusetts. "a"l represents the results of the actual Again column ounted flow; column "b" results from the author's adjustment so that the number of days per month would be equal. It should be pointed out that none of the groups of figures is a particularly good or error-less guide to the actual monthly traffic variation to and from Downtown Boston. The Sumner Tunnel counts are influenced by: the flow of traffic to Suffolk Downs and Wonderland Race Track during the spring and summer months, the flow of vacation traffic during the summer months, and the limitation of traffic flow during the summer months due to the operational capacity of the Tunnel. The count on Route 138 may not be indicative because it is affected by vacationists and joy-riders during the summer months. The figures used by the Massachusetts Department of Public Works are not considered representative of Downtown Boston travel and are presented only for interest and contrast. A set of figures has been selected that are similar to and vithin the spread established by the Sumner Tunnel and Route 138 variations. This selected variation is presented in Table VI. 25 Table VI - Showing the selected monthly variation of motor vehicle flow to Downtown Boston in 1950. Percent Deviation Month .80 .82 .88 1.00 1.10 1.14 1.16 1.15 1.04 1.02 1.00 .95 January February March April May June July August September October November December 6. The 1950 cordon count records those motor vehicles that passed through Downtown Boston as well as those destined or originating in the area. This thesis is not concerned with those passing through except to eliminate them from-the cordon count totals. The Origin and Destination Survey made in 1945 offers the only information available regarding the magnitude of this type of travel. The O&D survey indicates that 16.8% of the motor vehicles that enter Downtown Boston continue through. This amount has been deducted from the total amount entering and leaving according to the adjusted cordon count. The remainder is the number of vehicles that have origins or destinations in the Downtown Area. By using this figure in the manner outlined, it is assumed that the proportion of through traffic was the same in 1950 as it was in the fall of 1945, and that the proportion of through traffic is constant from month to month. 26 7. To transform motor vehicle counts into person movements, the results of a survey made by the author during the month of May, 1953, have been used. This survey, which counted 13,000 passenger cars as they entered and left Dcwntown Boston (a 2.5% sample) on various major streets between 7 a.m. and 8 p.m. on a Tuesday, Wednesday, and Thursday, established that the average number of occupants per l ssenger car was 1.57. This figure has been used here. In using this 1.57 ratio the following assumptions are made: that the number of occupants per vehicle was the same in 1950 as in 1953, that the number of occupants per vehicle did not fluctuate from month to month, and that the ratio applies to Downtown Boston destined traffic although motor vehicles passing through the area were included in the count. The number of occupants per truck has been assumed as 1.40. This is not the result of a survey, as such, but the result of untabulated observation, and examination of traffic reports of other large cities. Concerning the adjustments made to MTA information 1. March is not an average month for travel via MTA. The variation of monthly travel has been established from MTA records that show the total revenue collected in all Downtown Stations (except Devonshire and Mechanics) for each month dul. ng 1950. Table VII presents this acceptable monthly variation. The figures represent the deviation, expressed as a percent, of each month from the "average month". 27 Table VII - Showing the monthly variation of MTA riders to Downtown Boston in Month Percent Deviation a b 1.09 1.06 1.08 .99 1.11 1.085 1.02 1.035 1.045 1.03 .98 .97 .81 .83 .89 .87 .93 .94 1.00 .99 1.05 1.03 1.12 1.13 January February March April May June July August September October November December Column "a" 1950. is the result of the actual count; column "b" has been adjusted for a constant number of days per month. The figures in column "b" have been used here. 2. The March 22, 1950, count included those persons paying fares in the Downtown Area and traveling to other parts of the Downtown Area. These person-trips are not part of those destined for, or originating in, the Downtown Area and traveling elsewhere. count totals. This group has been deducted from the fare The 1945 0 & D survey indicates that this group represents 10.5% of the total amount of persons boarding the MTA in the Downtown Area. In deducting this amount it is assumed that the proportion of intra-downtown MTA riders to total Downtown MTA riders has not changed from 1945 to 1950. It is further assumed that the proportion of intra-area travel is constant from month to month, 28 Concerning the adjustment made to railroad travel information The only adjustment to railroad travel data that has been made is to correct for monthly variation. The adjustment is based directly upon information obtained from the rail companies, and is presented below. Table VIII - Showing the monthly variation of rail riders to Downtown Boston in 1950. Month January February March April May June July August September October November December Percent Deviation b a 1.12 1.13 1.01 1.08 1.03 1.04 1.03 1.00 .99 1.00 .98 .96 .955 .95 .94 .93 .95 1,02 .97 1.02 1.03 1.04 .93 1.04 Column "a" is the result of the actual count; column "b" has been adjusted for a constant number of days per month. The figures in column "b" have been used here. 29 Appendix - II Concerning the method of relating the amount and type of uses with the number of person-trips, It has been recognized from the outset that the relationships sought could not be obtained from a pure mathematical The fact that x, y, z, and w, the unknowns, do process. vary from zone to zone (because of differences in type of establishments, building design, location, etc.) introduces limitations in the process of solving the equations simultaneously. The more general relationships can be established, however, if care is used in selecting the most useful equations, and if they are handled in a manner cance of the numbers. that retains the signifi- Specifically, it has been found neces- sary to first solve for the most influential members of the equations (or first eliminate those members that have least influence upon the final product) and in addition, cause -the least possible change in the value of the numbers in the equations. a. The procedure used is as follows: Because there are but four unknowns, six of the zone equations have been combined into four of approximately equal value. The data representing zones 3, 12, and 16 have been combined into one equation and related to equations 4, 5, and 6. The simultaneous equating process first eliminated z and w, and then x. Values of y and x were obtained; values which are the average generating power for all office and all retail accommodations in the business district (except zone 17). The equation for zone 17 has not been used in the solving process. This area ia a very special kind in that it 30 contains a large amount of wholesale-retail furniture establishments which the accommodation inventory has classified as retail. The generating power of these establishments is not as great as other retail facilities and including this zone in the analysis distorts the results. This distortion has been avoided by omit- ting the numbers representing zone 17 from the calculations. It is also to be noted that the 102,000 person- trips made to zone 6 includes approximately 5,000 trips originating or destined for the residential sections of the zone. This amount has been deducted from the total number of trips to zone 6. b. Values for x and y somewhat greater or less than the average have been selected (as based upon a potential inaccuracy of the previously determined person-trip data, a knowledge of the kind of establishments in each zone, and maintaining the average generating power for all accommodations) and inserted into the original zone equations. (Equations 12 and 16 become practically s lved because of the insignificance of z and w.) c. Using selected values of x and y, equations 3, 4, and 5 and 6 are reduced to two unknowns, These equations have been solved mathematically after combining 3 with 4, and 5 with 6 (or 3 with 6, and 4 with 5). The values of z and w have also been expressed as a range. d, Selected values of x, y, z, and w have been inserted into the original zone equations so that the most influential and significant unknown could be solved for. 31 The values that were inserted were allowed to vary so that a range of numbers could be obtained for each of the sought unknowns. e. Steps b, c, and d were repeated until a range covering apparent minimum and maximum values of each unknown had been established. Presumably, therefore, within each range is the average generating power of all accommodations in the business district as well as the average generating power of most all the accommodation types within each zone. Table IX - Showing each of the equations used in the cal- culations with selected values substituted for the unknowns, This demonstrates that reasonable values for the unknowns (selected from within the ranges presented on page 20) can The first group of numbers in each solve each equation. equation refers to retail, consumer services facilities; the second group, office facilities; the third, manufacturing and utilities facilities; the fourth, wholesale and storage facilities; and the single number representing the sum of the four groups is the number of person-trips. The numlerator of each fraction is the number of square feet of accommodations; the denominator is the generating power value expressed here as the number of square feet per person-trip (the inverse of x, y, z, and w). Zone 3. Zone 4 $ 1100 -10 / 2300 230 27,000 / 8700 / 2240 / 2880 87,000 6360 2810 1230 ~~0 ~175 / 475 1180 ~8 Zone 5 (Accommodations are in 000's of square feet.) / 200 7 0 ~ 32 ~117 TO / ~36 540 ~75 122,000 Zone 6. 4500 / 3000 / 2000 / 2400 97,000 350~ Zone 12. Zone 16. Table X - 2340 660 W6~ / 3770 / 2250 19~5~ /' 180 IU 3 /320 / 230 ~ 42,000 20 = 21,000 73U / To Showing an equation representing the entire business district with selected average values substituted for the generating power unknowns. The components of the equation are the same as the equations in TableIX. Business District 16580 85 7 20820 ~I85~ 33 / 8790 ~1728 / 10030 412,000