Transit-Accessible Child Care Study
Prepared for the Northern Virginia Transportation Commission
Claire Daly, Kenneth Derryberry, & Michelle Millirons
Urban and Environmental Policy and Planning, Virginia Tech
UAP 5126: Planning Studio
Dr. Margaret Cowell mmcowell@vt.edu
May 5, 2025
Executive Summary
This study highlights the critical link between childcare accessibility and high-frequency public transit in Northern Virginia. This analysis, done on behalf of the Northern Virginia Transportation Commission (NVTC) by students of the Virginia Tech Master of Urban and Regional Planning program, examines this relationship through the creation of four maps displaying high-frequency transit, existing childcare facilities, and different demographics of interest.
Although the region contains a substantial number of licensed childcare facilities and a significant population of young children, only 11% of childcare facilities are within the pedestrian shed of high-frequency transit stops. This poses a major barrier to working families, especially those who rely on transit and reside in areas without frequent service. Lines like Metrobus 7A, 7M, 16M, and Metroway lack adequate access to childcare facilities. On the other hand, some areas with plenty of childcare seats have little to no access to the high-frequency transit network.
In general, the eastern part of NVTC’s jurisdiction, primarily Arlington and Alexandria, is far better served by the high-frequency network than most other areas. Communities around Dulles Airport and throughout Loudoun County and western Fairfax County lack sufficient access, despite some areas with high demand. We recommend increasing frequency on key existing transit routes to better serve these areas. Further, transit agencies should incorporate childcare into transit-service plans going forward to help transit-reliant parents. This can be done through measures such as co-locating childcare near transit hubs and ensuring future transit planning considers the mobility needs of families.
Introduction
Childcare is necessary and essential infrastructure. Without access to childcare, working is difficult or, in many cases, impossible. However, in the U.S , childcare has long been in short supply with significant disparities in availability across neighborhoods. Most studies on job access and commuter travel are based on the idea that commuters travel directly from home to work, but over 25% of all work trips are chained (McGuckin, Zmud, & Nakamoto, 2005). This means that workers make a trip on their way to or from work, and often this includes parents or caregivers of young children stopping at a childcare center. Employment is predicted not only on access to jobs, but also the ability to easily access childcare before and after work (Blumenberg, Wander, & Yao, 2024) For most single parents who rely on transit for travel, transit-accessible childcare is crucial.
The Northern Virginia Transportation Commission (NVTC) is a regional forum for the discussion and analysis of transit issues that are critical to the economy and quality of life. They plan, coordinate, and secure funding for transit systems in the Northern Virginia area. Their jurisdiction includes Arlington County, Fairfax County, Loudoun County, the City of Alexandria, the City of Fairfax, and the City of Falls Church. Students and staff of the Master of Urban and Regional Planning (MURP) program at Virginia Tech expressed interest in conducting a study on transit-accessible childcare, particularly the ability of families to access childcare via public transportation in Northern Virginia. NVTC agreed to act as a practitioner partner to help guide the students in the preparation of a study of Northern Virginia, modeled after the “Transit-Accessible Child Care Study” prepared for Metro Transit in Minnesota’s Twin Cities (Valorose, 2016)
Research Approach
This study focuses on addressing the following three research questions. First, how many childcare facilities within NVTC’s jurisdiction of Northern Virginia are within an easy pedestrian distance of high-frequency transit stops? Second, is the supply of transit-accessible childcare adequate? Additionally, is there an adequate supply of childcare along the highfrequency transit network?
To answer these questions, four maps were created to overlay the location of existing childcare providers and high-frequency transit stops. The maps show these in the context of the concentration of children, cumulative demand, job centers, and areas of concentrated poverty.
Key Definitions
The study uses the following definitions as it refers to transit-accessible childcare throughout this report:
• Childcare: A combination of all the childcare centers, family childcare homes, and preschools, as provided by Child Care Aware of Virginia.
• Childcare capacity: The total number of spots licensed to operate at each childcare center
• High-frequency transit: Transit stations on routes with consistent, bi-directional headways of 12 minutes or less for at least two hours between 6:00am and 9:00am and between 4:00pm and 7:00pm Monday-Friday. This headway is practical and useful for most parents with children.
• Easy walking distance: For rail, ½ mile pedestrian shed (pedshed). For bus, ¼ mile pedshed.
A typical trip using transit to access childcare includes a parent or caregiver starting at their home, taking transit to their childcare destination, and then traveling from there to their place of work.
The NVTC high-frequency network comprises 16 routes operated by multiple transit agencies. After each timetable was reviewed for every route within the jurisdiction of the NVTC,
they were compared to the definition of “high frequency” as defined above. Ultimately, 16 routes were pulled to be used as the high-frequency network for the study:
• WMATA Metrorail: Blue, Orange, Silver, and Yellow lines1
• WMATA Metrobus: Metroway, 7A, 7M, 16M, and 28A
• ART: Routes 41, 43, and 552
• DASH: Routes 30, 31, and 353
• Fairfax Connector: Routes 423 and 6604
Mapping
GTFS data from March 2025 were used to map and analyze transit stops, routes, and pedsheds using ArcGIS Pro. Licensed childcare facility data from Child Care Aware Virginia was mapped within these pedsheds to assess proximity to transit. Demographic data from the U.S. Census was also spatially analyzed in comparison to the high frequency network. The results were visualized through various thematic maps, and further demographic and childcare facility analyses were performed within and outside the high-frequency network to support planning and equity evaluations. Appendix A contains a full description of the methodology for this report.
To show the “supply” of childcare, all maps show the location of licensed childcare providers and their size, based on their capacity to serve children under age 6. Since there is no single way to calculate demand for childcare, “demand” was estimated four ways. All the maps described below can be found in Appendix B:
1 WMATA, which stands for Washington Metropolitan Area Transit Authority, operates public rail (Metrorail) and bus (Metrobus) services in Maryland, Washington, D.C., and Virginia.
2 ART, which stands for Arlington Transit, is the public bus service operated by Arlington County, providing transit throughout the county.
3 DASH is the City of Alexandria’s public bus network, operated by .
4 The Fairfax Connector is the public bus network operated by and servicing Fairfax County.
• Map A examines where children under age 6 are living, and which census blocks have the highest density of young children.
• Map B shows the cumulative demand for childcare for each pedshed. Cumulative demand considers two different types of childcare facility demand, the local demand as well as surrounding demand. Local demand is the number of potential childcare clients (children under age 6) who live in that pedshed. Surrounding demand is the number of potential childcare clients who could reach that pedshed within a 30-minute trip along the highfrequency transit routes.
• Map C highlights regional activity centers and job density at the transportation analysis zone (TAZ) level to illustrate where individuals within NVTC’s jurisdiction are employed.
• Map D highlights the low-income concentration based on the number of people below 80% Area Median Income (AMI) per acre.
Findings
Across the NVTC’s six jurisdictions, an estimated 102,239 children under the age of six live in households where all parents are in the workforce. These households likely require more formal childcare options than those with a stay-at-home parent. However, only 11% of childcare facilities are in the high-frequency transit network, indicating limited access to childcare through these transit services. A more detailed breakdown by jurisdiction is provided in Appendix C.
Map 1A illustrates the high-frequency transit network, the locations of childcare facilities, and the distribution of children under six across the NVTC jurisdictions. This data reveals three key trends:
• First, most young children reside in the eastern part of the region. Approximately 77% of children under six live in Arlington County, Fairfax County, the City of Alexandria, the City
of Falls Church, or the City of Fairfax. Fairfax County alone accounts for nearly 57% of this population, reflecting its overall population share in the region.
• Second, the distribution of childcare facilities generally aligns with the population density of young children. Most facilities are concentrated in the eastern jurisdictions, with noticeable clusters around Dulles Airport.
• Third, high-frequency transit services are primarily available in Arlington County and the City of Alexandria, with some coverage in the City of Falls Church and portions of Fairfax County, particularly along corridors leading to Dulles Airport and Centreville. However, many areas in the region, including those with a high concentration of children under six and a high volume of childcare facilities, lack access to high-frequency transit.
The following sections offer a detailed review of the analysis of four key demand estimates to better understand the state of childcare accessible by high-frequency transit in the NVTC jurisdictions. This study focuses on two priority areas. The first is the “central core," defined for this study as the area including Arlington County, the City of Falls Church, the City of Alexandria, and the eastern part of Fairfax County. The other priority area is the western part
of Fairfax County and the eastern part of Loudoun County. This priority area includes the “Dulles Donut”, defined as the communities surrounding Dulles Airport.
Concentration of children
Map 2A shows the concentration of children under six in the NVTC jurisdictions, overlaid with the high-frequency transit network and childcare facility locations. The highfrequency transit network effectively serves the central core, where the density of the under-six population is notably the highest of the NVTC jurisdictions. However, most transit-accessible childcare facilities are in Arlington County and the City of Alexandria.
Throughout the NVTC, only about 11% of childcare facilities and 14% of the total childcare capacity are within the high-frequency transit network. Over half of these facilities and their total capacity are in Arlington County and the City of Alexandria. Approximately 8% of childcare facilities accessible by high-frequency transit are in this area, representing about 11% of the total capacity. Yet, in Arlington County and the City of Alexandria, more children under six, including children from households with all parents working, live outside the high-frequency
2A. Maps illustrating children's concentration, the high-frequency network, and childcare facilities throughout the NVTC jurisdictions. The map on the left highlights the NVTC’s central core, while the map on the right emphasizes the Dulles Donut.
network than within it. Over 50% of children in both localities live outside the high-frequency network.
In contrast, areas along the Beltway, such as Annandale, have a high concentration of children in this demographic but limited or no access to high-frequency transit. Along I-66, the high frequency network extends to Centreville but has few stops, reducing access to nearby childcare options. Similarly, the Dulles Donut area has many young children and numerous childcare facilities but is supported by a single high-frequency line, the Metrorail Silver Line. This line only provides access to two childcare facilities within easy pedestrian distance of a high-frequency transit stop.
Cumulative demand
Cumulative demand measures the number of children who can reach a childcare facility within a 30-minute travel window. This includes walking time to and from a station, waiting, and time spent on public transit. In effect, it combines both local and surrounding demand.
Map B highlights areas with the highest cumulative demand for childcare facilities. Southern Arlington County and the northwestern portion of the City of Alexandria emerge as areas with the most substantial cumulative demand, suggesting a prime location to expand
Map B. Maps illustrating cumulative demand, the high-frequency network, and childcare facilities throughout the NVTC jurisdictions. The map on the left highlights the NVTC’s central core, while the map on the right emphasizes the Dulles Donut.
childcare facilities accessible by high-frequency transit. Around 20 facilities, including several large childcare centers, are located here and are accessible via high-frequency transit. In contrast, the Dulles Donut has low cumulative demand, mainly due to limited transit connectivity, despite the presence of many children and existing childcare providers.
Job and activity centers
Proximity to job and activity centers can also influence childcare accessibility. Map C shows many dense job centers in the central core, especially in Arlington County and certain parts of Alexandria, such as Old Town and Eisenhower Avenue. As discussed above, these areas benefit from high-frequency transit services and have many existing childcare facilities.
However, high-frequency transit service does not adequately serve job centers near the Beltway, Annandale, and along the I-66 corridor, which limits access to childcare facilities for working parents in these areas. Similarly, despite having numerous jobs and childcare options, the Dulles Donut area lacks sufficient high-frequency service, making it difficult for parents to access childcare facilities during their daily commutes to and from work.
Low-income concentration
Map D maps low-income populations across the region and their access to childcare accessible by high-frequency transit. The Arlandria and Four Mile Run neighborhoods in the central core have many low-income residents but no access to frequent transit services. The population of children under six in these neighborhoods is moderately dense, yet fewer and smaller childcare providers are available. Therefore, current transit access to better-served areas depends on less frequent public transit services
Low-income populations are concentrated around the Beltway and Annandale, areas that lack high-frequency transit options despite having many high densities of children under six and jobs. Additionally, many low-income residents live within an easy pedestrian distance of these transit stops. The lack of additional high-frequency transit routes nearby may limit access to childcare facilities outside these immediate areas.
The cumulative demand analysis further underscores this gap. Children living near the end of transit lines, such as in Centreville or past Dulles Airport, are unlikely to reach a childcare provider via high-frequency transit within a reasonable timeframe, even when facilities exist nearby.
High-frequency service evaluation
In addition to spatial analysis, this study evaluated childcare access along each NVTC highfrequency transit network route. A qualitative rating system classified access as low, medium, or high based on how effectively each route provided high-frequency transit access to childcare facilities. This assessment considered the four demand estimates and childcare facilities' presence, frequency, and capacity within the route's pedsheds.
Table 1 summarizes the findings for each of the 16 routes in the NVTC high-frequency network. Five bus routes, four of which are WMATA Metrobus routes serving Arlington County and the City of Alexandria, were rated as having low childcare access. The Metroway and 16M routes are particularly notable because both serve areas with high concentrations of children, medium to high cumulative demand, substantial job densities, and a significant share of lowincome residents. Few childcare facilities are within an easy pedestrian distance from stops along these routes, indicating that even high-frequency routes may fall short of meeting childcare access needs.
Table 1: Summary of Route Evaluations
Routes that received a high childcare access rating scored well across all four demand estimates. These routes also had a higher and more even distribution of childcare facilities within an easy pedestrian distance of many bus stops. The highest-ranking routes were the WMATA Metrorail Yellow and Silver lines, the WMATA Metrobus 28A, and DASH Route 31.
In contrast, the seven routes with medium childcare access generally had lower scores in one or more demand estimates and gaps in childcare facilities accessible along the route. These
routes include two WMATA Metrorail lines, all three ART bus routes, two DASH routes, and one Fairfax Connector route.
Recommendations and Further Research
Within the high-frequency network, it is important to ensure childcare access along those lines with high demand. The Metrobus routes 7A, 7M, and 16M, and Metroway are examples of high-frequency routes with high demand, but low childcare access, as demonstrated in the findings table. Childcare centers should be intentionally co-located with the high frequency network lines with high demand and with residential neighborhoods and job centers In general, planners should proactively increase childcare capacity along the existing high-frequency network. They may also consider pairing, or developing incentives for, childcare with transitoriented development or economic development campaigns that would do so.
In addition to areas where high-frequency transit exists but childcare access in lacking, there are also places where the opposite is true. Some areas have significant supplies of childcare, but no high-frequency transit connecting the centers to families. One example of this is the eastern part of Loudoun County and the western part of Fairfax County, highlighted in Figures 1 and 2 . Traditionally, transit planning heavily emphasizes job access, housing density, and recreational areas Childcare access should also be treated as a critical land use and service need because it fundamentally supports working families.
To better support the transit accessibility of these locations, we recommend that NVTC agencies work to implement high-frequency service on existing lines by increasing headways to 12 minutes or less on key routes. As per Table 2, we have recommended three routes per bus agency, in order of our perceived significance, on which to prioritize high-frequency service attempts.
WMATA 1 REX 15 minutes
WMATA 2 16A 15-30 minutes
WMATA 3 1C 30 minutes
Serves children, low-income people, jobs, and existing childcare along Richmond Highway, which currently has no highfrequency transit
Serves children, low-income people, jobs, and existing childcare along US-29 and in Fair Oaks and Merrifield, adding more HFN stops along I-66 corridor
Serves children, low-income people, jobs, and existing childcare in Lake Barcroft and Annandale ART 1 45 15 minutes
Serves children, low-income people, jobs, and existing childcare along Washington Boulevard south of Clarendon, S Courthouse Road, and Columbia Pike; connects to Rosslyn-Ballston corridor childcare
ART 2 42 15 minutes
Serves children, low-income people, jobs, and existing childcare along Washington Boulevard south of Clarendon and along S Courthouse Road, as well as along Columbia Pike and in Pentagon City; connects to Rosslyn-Ballston corridor childcare ART 3 87 10-20 minutes
Serves children, low-income people, and existing childcare in Green Valley and Long Branch Creek; connects to Pentagon City childcare
DASH 1 36 15-30 minutes
DASH 2 33 30 minutes
DASH 3 32 30 minutes
FC 1 401/402 ~15 minutes
Serves children, low-income people, and existing childcare in Arlandria; connects to childcare and high-frequency network with highest cumulative demand near Southern Towers and Mark Center
Serves children, low-income people, and existing childcare along Mount Vernon Avenue; connects to childcare in Old Town
Adds additional high-frequency service between West Alexandria and Old Town’s existing childcare capacity
Serves children, low-income people, jobs, and existing childcare along the Beltway, including Annandale; connects to existing
FC 2 901 30-40 minutes
FC 3 950 15 minutes
CUE 1 Gold 30 minutes
CUE 2 Green 30 minutes
LCT 1 381 25-40 minutes
childcare along Metro Silver, Orange, and Blue lines
Serves children, low-income people, jobs, and existing childcare along the eastern side of the Dulles Donut and Centreville
Serves children, low-income people, jobs, and existing childcare in Reston, Herndon, and McNair
Serves children, jobs, and existing childcare in Fairfax; one of the two CUE routes
Serves children, jobs, and existing childcare in Fairfax; one of the two CUE routes
Serves children, low-income people, jobs, and existing childcare along the southern side of the Dulles Donut in South Riding
LCT 2 70 30 minutes
LCT 3 322 60 minutes
Table 2: Summary of Recommendations
Serves children, low-income people, jobs, and existing childcare along the northern side of the Dulles Donut, including Leesburg, Landsdowne, and Dulles Town Center
Serves children, low-income people, jobs, and existing childcare along the eastern side of the Dulles Donut, including Sterling and Dulles Town Center
Finally, renovating or building new childcare with considerations of how pedestrians can access it via transit is recommended. Ensure that parking lots, sidewalks, and building entrances are pedestrian friendly. These considerations can shave time off a pedestrian’s trip and makes travel easier for busy parents.
A continued study of transit-accessible childcare is needed, including the creation and analysis of a low-frequency network, representing all transit routes within NVTC, to examine the shares of children and childcare with at least some transit access. This could support recommendations for where to improve headways on the existing network and where to add new transit or redesign routes. Children, childcare, and other demographic factors could be compared between the high-frequency network, the low-frequency network, and areas outside Further
research could also break down childcare facilities by type between childcare centers, family childcare homes, and preschool programs.
References
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Blumenberg E., Wander M., & Yao Z. 2024. Decisions & Distance: The relationship between child care access and care travel. Journal of Transport Geography. https://www.sciencedirect.com/science/article/pii/S0966692323002284
Child Care Aware of Virginia. (n.d.). 2023 Program List [Data Set].
DASH. (n.d.). Schedules and Maps. Retrieved January 2025, from https://www.dashbus.com/schedules
Fairfax City. (n.d.). CUE Bus Map & Schedules. Retrieved January 2025, from https://www.fairfaxva.gov/government/public-works/cue-bus-mapschedule#Bus%20schedule%20anchor
Fairfax County. (n.d.) Schedules and Maps. Retrieved January 2025, from https://www.fairfaxcounty.gov/connector/schedules
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McGuckin, N., Zmud, J., Nakamoto, Y. 2005. Trip-Chaining Trends in the United States. SAGE Publications. https://journals.sagepub.com/doi/epdf/10.1177/0361198105191700122
Metropolitan Washington Council of Governments. (2025, January 17). TAZ Depiction of COG Activity Centers. Retrieved January 2025, from https://hub.arcgis.com/maps/mwcog::tazdepiction-of-cog-activity-centers-1/about
Metropolitan Washington Council of Governments. (2023, November 13). Cooperative Forecasts: Employment, Population, and Household Forecasts by Transportation Analysis Zone. Retrieved January 2025, from https://www.mwcog.org/documents/2023/11/03/cooperative-forecasts-employmentpopulation-and-household-forecasts-by-transportation-analysis-zone-cooperativeforecast-demographics-housing-population/
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Washington Metropolitan Area Transit Authority API. (n.d.). Rail & Bus Combined GTFS Static [Data set]. Retrieved March 17, 2025, from https://developer.wmata.com/apidetails#api=gtfs&operation=rail-bus-combined-gtfs-static Valarose, J. 2016. Transit-Accessible Child Care Study. Metro Transit. https://www.metrotransit.org/Data/Sites/1/media/tod/child-care-study-final-report.pdf
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Appendix A: Methodology
High frequency network
In identifying the high frequency network, we first established our definition of frequent service. For a headway, we chose to follow WMATA’s definition of frequent service being a transit vehicle arriving every 12 minutes or better. We also selected this headway thinking of parents trying to get to work on transit, with children in tow to be dropped off at childcare along the way. While some might be able to plan around less frequent schedules, a network of service every 12 minutes means waiting 6 minutes on average for a transit vehicle.
For directionality, we settled on only bidirectional linear service, excluding one-way service such as commute-focused lines traveling only to the region’s core in the morning and only from the core in the evenings. This was because we knew we would be measuring cumulative demand and estimating the utility of childcare providers to surrounding areas. If these centers can only be accessed from one direction, they cannot be fully accessed by transit from either direction and our analysis would be skewed.
For days and times of the week, we were focused on weekdays and commute hours for jobs with standard business hours. While parents working outside of these windows likely require childcare as well, a significant portion of parents work during standard business hours and would be seeking childcare during that time. Further, most transit schedules are built with commutes to those types of jobs comprising peak service periods, in the morning and in the late afternoon. Therefore, we wanted to identify all routes providing 12-minute frequencies or better during the morning and late afternoon peak periods. While WMATA Metrorail and some other agencies set their peaks from 7 am to 9 am in the morning and 4 pm to 6 pm in the afternoon, the size of the region and the distance of its commutes means some agencies, especially further out jurisdictions like Loudoun County, set their peaks earlier or later. To increase flexibility, we
counted any routes as high-frequency that had a continuous 2-hour period of 12-minute headways or better in both the morning and late afternoon; for instance, 6 am to 8 am and 5 pm to 7 pm qualified.
With these definitions solidified, timetables were reviewed for every route of every NVTC transit agency. Every headway in every timetable was calculated in search of any routes that would qualify Ultimately, 16 routes were determined to comprise the NVTC high-frequency network: the WMATA Metrorail Blue, Yellow, Orange, and Silver lines; the WMATA Metrobus Metroway, 7A, 7M, 16M, and 28A; the ART 41, 43, and 55; the DASH 30, 31, and 35; and the Fairfax Connector 423 and 660. Due to branching and different service patterns, the portions of Metrobus Route 7A from Southern Towers to Van Dorn Metro Station and the routing option through Pentagon City, and the portion of DASH Route 30 from Landmark Transit Center to Van Dorn Metro Station were not included in the high-frequency network, as they did not meet the criteria.
For the most up to date data, GTFS files were downloaded on March 17, 2025, for all NVTC transit agencies. GTFS TXT files for routes, trips, stop times, and stops were joined in R to create tables including coordinates and route numbers. We entered these tables into ArcGIS Pro and created point shapefiles of NVTC transit stops by agency. These were merged to create a shapefile of all bus stops and a shapefile of all Metrorail stations, which were both clipped using an NVTC jurisdiction polygon shapefile5 to remove stops in Prince William County or further south in Virginia, in DC, or in Maryland. Line shapefiles for the high-frequency routes were also created from the GTFS files.
5 Downloaded from R using tidycensus; see “Demographic data” for more information.
To analyze access for people, childcare, and jobs to transit stops, we created pedsheds6, a polygon that calculates the area that can be reached by pedestrian trips of a certain distance along the existing street and sidewalk network. Industry standards utilize a quarter mile distance as the easily reachable pedestrian distance from bus stops and a half mile distance from rail stations; these were the distances we used for Metrobus, ART, DASH, and Fairfax Connector stops and Metrorail stations, respectively. We used the ArcGIS Pro Network Analyst tool to measure service areas. Due to different pedshed distances, bus stops and rail stations were run separately. Service areas of quarter mile and half mile walking trips were calculated for each stop in the high frequency network. This generated the high frequency pedshed, which was utilized individually to measure cumulative demand for each stop and dissolved into one polygon for all other analyses.
Childcare data
Child Care Aware Virginia (CCAoVA) is a non-profit organization that advocates for high-quality childcare in Virginia. As part of its mission, CCAoVA collects and maintains annual data on the number, type, and capacity of licensed childcare facilities throughout the state. For this study, CCAoVA provided a list of the licensed childcare facilities operating in 2023, categorized by type, such as childcare centers, preschools, and family day homes, along with capacity information and their geographical coordinates (X and Y) for each jurisdiction served by the Northern Virginia Transportation Commission (NVTC), which includes Arlington County, Fairfax County, Loudoun County, the City of Alexandria, Fairfax City, and the City of Falls Church.
6 Pedsheds is a more inclusive term for walksheds, because it includes non-walking pedestrian trips for people using mobility devices. While the names are different, they measure the same thing.
Using ArcGIS Pro, the X and Y coordinates from the datasets were converted into points, allowing for mapping licensed childcare facilities within NVTC's jurisdiction along with their capacity data. This mapping was critical for developing demand estimates across all four areas. We selected childcare facilities within the high-frequency network and created a new field, labeling whether these points were inside or outside the high-frequency network.
Demographic data
Census data was acquired using the tidycensus package in R. American Community Survey 5-year data (2018-2023) was selected at the census block group level for the NVTC jurisdictions. The variables selected were: total population, population below age six (children), population under six with two parents both working, population under six with two parents and father working, population under six with two parents and mother working, population under six with two parents and neither working, population under six with one parent (father) who was working, population under six with one parent (mother) who was working, population under six with one parent (father) who was not working, and population under six with one parent (mother) who was not working. These variables were summed to create a variable for children with all parents working, representing children with two parents both working or only one parent who was working, which was used to suggest the most significant childcare “demand.”
Data for low-income people was acquired from the US Department of Housing and Urban Development, utilizing a shapefile of low to moderate income people by census block group, found by comparing incomes of individuals to the area median income. For the NVTC jurisdictions, the fair market rent area used to determine area median income is the WashingtonArlington-Alexandria, DC-VA-MD metropolitan statistical area. The dataset defined low income as up to 50% of the area median income and moderate income as up to 80% of the area median income Data for the total number of low- and moderate-income people per census block group
was used. Since the dataset contains information for the entire United States, the data was subset by county to select only NVTC jurisdictions.
The dataset for low-to-moderate-income people by census block group and child population data by census block group were joined in ArcGIS Pro. The density of each was determined by dividing the total number of children under six and the total number of low-tomoderate-income people in each census block group by the area of the census block group in acres, generating a number of children per acre and a number of low income people per acre; these represent the estimated densities of each per census block group.
Jurisdiction borders
The joined NVTC census block shapefile containing demographic and low-income data was dissolved by county to generate a jurisdiction borders shapefile. Additionally, all census blocks were dissolved into one to create an NVTC boundary shapefile, which was used to clip data layers extending beyond the NVTC area.
Job data
Shapefiles from the Metropolitan Washington Council of Governments were pulled for Regional Activity Centers and transportation analysis zones (TAZs), and data was pulled from the Round 10 Cooperative Forecasts for employment by TAZ. Total employment for 2020 was divided by area of each TAZ to determine a total job density per acre, which was joined to the TAZ shapefile. Job density TAZs and Regional Activity Centers were clipped by the NVTC boundary shapefile to select those comprising the study area.
Cumulative demand
Individual pedsheds for each high-frequency transit stop were used. The tabulate intersection function was used in ArcGIS Pro, which overlaid each pedshed on the census block group data of total population under six. This function estimated the total number of children in each individual pedshed by calculating the percentage of each census block group that fell within each pedshed and taking that percentage of the census block group’s total children value; the proportional values for child population of each census block were summed by the function to estimate a total number of children within each pedshed. The total number of children in each pedshed was then joined back to the associated point for each transit stop.
To calculate cumulative demand, we assumed pedestrian travel times to and from each transit stop and the amount of time waiting for a transit vehicle. For bus pedsheds, a quarter mile distance equates to a roughly 5-minute pedestrian trip to and from each station from the edge of the pedshed, so we assumed a 5-minute pedestrian trip time. For rail pedsheds, a half mile distance equates to a roughly 10-minute pedestrian trip, so we assumed a 10-minute pedestrian trip time. For transit vehicle wait time, we estimated 5 minutes. Ten out of sixteen high frequency routes have 10-minute headways, equating to an average wait time of 5 minutes for a vehicle. Five have an average wait time of 6 minutes (12-minute headway) and one has an average wait time of 3 minutes (6-minute headway).
To calculate the cumulative demand of children to each pedshed within a 30-minute combined pedestrian and transit trip, we therefore assumed (for buses) a 5-minute trip to the stop, a 5-minute wait for a vehicle, and a 5-minute trip to childcare at the end of the trip. This left 15 minutes for in-vehicle travel time. We calculated average bus speeds by averaging the average bus speeds of ART, DASH, CUE, and Fairfax Connector, based on NVTC data. This resulted in an average speed of 11.28 miles per hour for buses, which could travel 2.82 miles in 15 minutes. For rail stops, we assumed a 10-minute trip to the stop, a 5-minute wait for a vehicle,
and a 10-minute trip to childcare at the end of the trip. This left 5 minutes for in-vehicle travel time. For average rail speeds, we used the average WMATA speed from NVTC data, which was 17.99 miles per hour Rail vehicles at this speed could travel 1.50 miles in 5 minutes.
Buffers were created around each high-frequency transit stop, with a 2.82-mile distance for bus stops and a 1.50-mile distance for rail stops, based on the cumulative demand assumptions and calculations. The tabulate intersection analysis selected all other transit stop points within each stop’s buffer and added the total number of children value for each stop’s pedshed. This created a total cumulative demand value, representing an estimated number of children within a 30-minute combined transit and pedestrian distance of each pedshed.
Maps
The combined pedshed layer was symbolized with transparency, so that data layers below it could be seen. High-frequency transit lines were added to each map. Childcare facilities were symbolized with proportional symbols, sized based on the licensed capacity of childcare at each location; the smallest licensed capacity of 4 had the smallest associated dot size, while the largest licensed capacity of 564 had the largest associated dot size. Additionally, dots were colored red if they were inside the high-frequency network and yellow if they were outside of it to visualize the difference. Childcare facility dots were made somewhat transparent so that data could be seen below them. Jurisdiction borders were added to each map.
For the concentration of childcare map, the number of children under six per acre were grouped into five manual interval classes for symbology. This was done to achieve round numbers easily interpretable to an audience. The five classes were 0, 0-0.5, 0.5-1, 1-5, and 5-20 children per acre. The classes were colored with a color ramp, with higher concentrations of children being shaded darker.
For the cumulative demand map, pedsheds were displayed individually rather than as a dissolved layer. Each pedshed was shaded based on its cumulative demand, with 5 manual interval classes: 0-5,000, 5,001-10,000, 10,001-20,000, 20,001-30,000, and 30,001-37,189 children within a 30-minute transit and pedestrian trip time. The classes were colored with a color ramp, with higher cumulative demand being shaded darker.
For the jobs and activity centers map, jobs per acre were grouped into five manual interval classes for symbology: 0, 0-0.5, 0.5-1.5, 1.5-10, and 10-320 jobs per acre. The classes were colored with a color ramp, with higher job densities being shaded darker. MWCOG Regional Activity Centers were displayed as outlines with no fill to demonstrate their location on the map.
For the low-income concentration map, people below 80% area median income per acre were grouped into five manual interval classes for symbology: 0, 0-0.5, 0.5-1.5, 1.5-5, and 5110. The classes were colored with a color ramp, with higher concentrations of low-income people being shaded darker.
Further analysis
Demographic data was broken down by geography for further analysis. The NVTC area was clipped by the high-frequency network dissolved pedshed, to create polygons for the area inside and outside of the high-frequency network within NVTC. These polygons were then clipped by the jurisdiction boundaries to create polygons for each jurisdiction’s geography inside and outside of the high-frequency network. The tabulate intersection analysis was used to estimate demographic values for each of the created geographies. A summarize within analysis calculated the total amount of childcare locations and capacity for each geography.
Appendix B: Demand Estimate Map Analysis
Appendix C: Table showing the ratio