What drives traffic

Traffic isn't growing. The school run is.

Every stretch of Boston Post Road carries less traffic today than it did in 1990, and on the busiest ones it has fallen sharply. More people take the train, work from home and shop online. But there is still one place a lot of people have to be at the same time every morning: school. That hasn't changed, and it's what drives the Post Road's traffic. On a morning with no school, a third of the traffic at one Post Road intersection disappeared.

Post Road traffic hasn't grown since 1990, and it fell after 2019

Mamaroneck is down a quarter since 2019 and Larchmont a quarter since 2014. The two Rye Neck segments have changed little.

Average annual daily traffic, both directions. Each dot is a year NYSDOT counted that segment. Segments are counted every few years, not every year, so the lines connect counts and don't show what happened in between.

Why daily traffic fell

About 8,800 Town of Mamaroneck workers drove to work in 1990. Today about 6,900 do, even though the town has more workers.

62% → 44%

drive to work, 1990 to today

Driving has fallen at every census count since 1990.

27%

work from home

Up from 7% in 2000. Since 2019, transit fell 11 points while working from home rose 19.

Fewer trips

to the store

E-commerce replaces shopping trips.

How Town of Mamaroneck workers get to work

Driving has fallen at every count since 1990. Before the pandemic the shift went to the train; since then, to working from home.

Share of workers 16 and over, by how they usually get to work. 1990 and 2000 are from the decennial census; the rest are 5-year American Community Survey estimates, plotted at their last year. The 1990 report gives driving and transit only. The 2020–24 estimate includes pandemic years, so working from home may settle somewhat lower. The Town of Mamaroneck includes Larchmont and part of the Village of Mamaroneck.

The exception: the school run

Schools are the biggest source of traffic and congestion in our area. Every student who is driven makes four car trips a day: drop-off, the drive home, pick-up, and the drive home again.

What we measured here

We measured it. In March 2024 we counted every vehicle through the Post Road intersection at Weaver Street and Hommocks Road, the road to Hommocks Middle School, from 8 to 9 am on two consecutive mornings. One was a normal school day. The other was a superintendent's day, when classes were canceled.

With no school, a third of the morning traffic disappeared

−33%2,069 vehicles on the school day, 1,396 on the superintendent's day
  • School day, Thu Mar 7, 2024
  • Superintendent's day, Wed Mar 6, 2024
  • Leaving Hommocks Road−82% 288 52
  • Turning into Hommocks Road−67% 423 140
  • Post Road through traffic−14% 972 833
  • Turns to and from Weaver Street−4% 386 371
Vehicles through the Boston Post Road / Weaver Street / Hommocks Road intersection, 8–9 am, counted by volunteers from video. One intersection, one hour, one pair of days.

The same morning, side by side

About eight minutes of morning traffic at the Post Road and Weaver Street / Hommocks Road, played at 4x speed, from the video volunteers counted.

Volunteer video, March 2024, sped up 4x: two minutes of video covers about eight minutes of traffic. No sound. Left: Wednesday, March 6 (superintendent's day). Right: Thursday, March 7 (school day).

The traffic that vanished was school traffic. Trips in and out of Hommocks Road fell by two-thirds or more, and even through traffic on the Post Road dropped by one car in seven. Ordinary turns to and from Weaver Street barely changed.

How our students get to school, school by school

Where parents say the route is unsafe, more kids are driven. At Mamaroneck Avenue, 64% of parents call the route unsafe and 73% of students are driven. At Chatsworth, 23% and 20%.

Left column in each pair: primary way each child gets to school. Right: share of parents who rated their child's walking or biking route somewhat or very unsafe. From the 2024–25 Mamaroneck and Rye Neck Safe Routes to School parent survey; driven includes carpools and high schoolers who drive themselves. Parents chose whether to respond, so families who already walk or bike may be overrepresented.

Ten schools, 6,000 students

Ten schools sit along Boston Post Road in Larchmont and Mamaroneck. They were a main reason Larchmont and both Mamaroneck governments asked NYSDOT to extend this work along the whole corridor.

Chatsworth Avenue
Central
Hommocks Middle
Mamaroneck High
Daniel Warren
F.E. Bellows
Rye Neck Middle
Rye Neck High
FASNY Manor
FASNY Harbor

Why don't more kids walk or bike? Two in three parents say it's too dangerous.

Share of the 493 parents in the 2024–25 Mamaroneck and Rye Neck Safe Routes to School survey who gave a reason their child doesn't walk or bike to school. Parents could pick more than one.

The national picture

The same shift has happened across the country, over two generations.

Nationally, the walk to school became a drive

In 1969, four times as many students walked or biked to school as were driven. By 2009 it had reversed.

  • 1969
  • 2009
Share of K–8 students (ages 5–14) by how they usually got to school, as reported by parents, from the same national survey question in 1969 and 2009. Among students living within a mile of school, walking or biking fell from 89% to 35%. The most recent national survey, in 2017, counted all children 5–17: 54% were usually driven, 33% took a school bus and 10% walked or biked.

Built for walking

Four of our six district schools were built between 1902 and 1925, in the middle of the neighborhoods they serve. Children were expected to walk or bike to them, and two still have no parking lot at all. Central, built in 1965, has a small lot, and the Hommocks lot wasn't enlarged when that school expanded in the 1990s.

Engraving of the 1902 Larchmont public school, a low stone building, with children walking up the path to the door.
Chatsworth Avenue SchoolOpened 1902Additions in 1912, 1922 and 1930. No parking lot.Larchmont's public school in 1904, from a bird's-eye view by Hughes & Bailey. Library of Congress.
Postcard of the original two-story Mamaroneck Avenue schoolhouse beside an empty dirt road.
Mamaroneck Avenue SchoolBuilt 1909Two stories at first; a third floor was added in 1916, and more in 1928. Built before most families had a car.Postcard, 1909–1916, before the third floor. Shared by John Gramaglia.
Postcard of Murray Avenue School with children walking in the street out front and no cars.
Murray Avenue SchoolBuilt 1922Additions in 1926 and 1930. No parking lot.Postcard, Brigham Stationery Shop. Larchmont Historical Society, Levi Collection.
Postcard of Mamaroneck High School's columned front and cupola, with an empty lawn and drive.
Mamaroneck High SchoolCompleted 1925Within walking distance of the neighborhoods it serves.Postcard, late 1920s. Image courtesy of Circle 7 Framing.
Historical photo to come
Central SchoolBuilt 1965A small parking lot.
Historical photo to come
Hommocks Middle SchoolBuilt 1968Expanded in the 1990s. The parking lot stayed the same size.

The streets around these schools can't absorb every child arriving by car. The road's hardest minutes are the school runs, and every child who can safely walk or bike is one fewer car in that line. Safer walking and biking is exactly what this project builds.

Sources
  1. NYSDOT traffic counts, Boston Post Road, 1990–2025
    Average annual daily traffic for four segments. Counts run from 1979; the chart shows 1990 onward.
    NYSDOT Traffic Data Viewer
  2. US Census Bureau, Means of Transportation to Work, Town of Mamaroneck
    1990: CPH-5-34, Table 5. 2000: Summary File 3, P030. 2006–10, 2015–19, 2020–24: ACS 5-year, B08301.
    1990 · 2000 · 2010 · 2019 · 2024
  3. Superintendent's day traffic count, Boston Post Road at Weaver St / Hommocks Rd
    Every vehicle, by movement, 8–9 am on Wednesday March 6, 2024 (no classes) and Thursday March 7, 2024 (school day), counted from video by Safe Routes to School volunteers.
  4. National Center for Safe Routes to School, “How Children Get to School: School Travel Patterns from 1969 to 2009” (2011)
    From the 1969 NPTS and 2009 NHTS: usual travel mode to school for K–8 students, as reported by parents.
    pedbikeinfo.org
  5. FHWA NHTS Brief: Children's Travel to School (2019)
    2017 NHTS, children 5–17: 54.2% usually driven, 33.2% school bus, 10.4% walked or biked.
    nhts.ornl.gov
  6. Mamaroneck Union Free School District, school histories
    Construction and addition years for each school, from the district's history page. Parking notes are Safe Routes to School's own observations.
    mamkschools.org
  7. Municipal resolutions, 2024
    Resolutions asking NYSDOT to bring Complete Streets to the full length of Route 1 (PIN 8473.15), each passed unanimously: Village of Larchmont, Village of Mamaroneck (January 8, 2024 agenda) and Town of Mamaroneck (January 2024).
  8. Mamaroneck and Rye Neck Safe Routes to School parent survey, 2025
    1,024 responses, one per child, from Chatsworth, Central, Murray, Mamaroneck Avenue, Hommocks and Mamaroneck High School; 18.5% of enrolled students overall.