Where do you think the most congested intersections are in Montgomery County? Maybe right by the Bethesda Metro? In downtown Silver Spring? University, Georgia, and Veirs Mill in Wheaton? Actually, no. A review of Montgomery County’s 50 most congested intersections found only one inside one of the county’s urban centers.

There are busy intersections in the more car-oriented neighborhoods around downtown Silver Spring, but not in the core. Map by the author.

County planners ranked the 50 busiest junctions for the Mobility Assessment Report, a regular review of Montgomery’s transportation needs. Notably, the report found that the amount of driving in the county has stayed the same since 2002 even while 100,000 new people came in.

The busiest intersection is Rockville Pike at West Cedar Lane in Bethesda, next to NIH and Walter Reed, which had a critical lane volume of 1,957 cars during morning rush hour. In other words, that means that nearly 2,000 cars pass through a single lane of that intersection each morning. In second place is Rockville Pike and Nicholson Lane in White Flint, which is slowly evolving into a new downtown.

Other than that, the top 50 didn’t contain a single intersection in the downtowns of Bethesda, Silver Spring, and Wheaton, in Friendship Heights, or Rockville Town Center. For decades, Montgomery County has had a policy of directing growth to walkable, urban neighborhoods near transit stations with an aim of reducing car traffic.

Rank Intersection Community AM CLV PM CLV
1 Rockville Pike at West Cedar Ln. Bethesda 1,957 1,612
2 Rockville Pike at Nicholson Ln. White Flint 1,234 1,929
3 Old Georgetown Rd. at Democracy Blvd. North Bethesda 1,423 1,923
4 Darnestown Rd. at Riffle Ford Rd. North Potomac 1,061 1,898
5 Shady Grove Rd. at Choke Cherry Ln. Rockville 1,363 1,853
6 Connecticut Ave. at East-West Hwy. Chevy Chase 1,684 1,848
7 Georgia Ave. at 16th St. Silver Spring 1,122 1,816
8 Great Seneca Highway at Muddy Branch Rd. Gaithersburg 1,464 1,800
9 Frederick Rd. at Montgomery Village Ave. Gaithersburg 1,536 1,795
10 Rockville Pike at 1st St./Wootton Pkwy. Rockville 1,768 1,610
11 East Gude Dr. at Crabbs Branch Rd. Derwood 1,742 1,211
12 Veirs Mill Rd. at Twinbrook Pkwy. Rockville 1,426 1,721
13 1st St. at Baltimore Rd. Rockville 1,422 1,718
14 Connecticut Ave. at Plyers Mill Rd. Kensington 1,349 1,710
15 Shady Grove Rd. at Epsilon Dr./Tupelo Dr. Derwood 1,704 1,403
16 University Blvd. at Piney Branch Rd. Silver Spring 1,579 1,703
17 East Gude Dr. at Southlawn Ln. Rockville 1,692 1,450
18 Randolph Rd. at Veirs Mill Rd. Wheaton 1,683 1,679
19 Piney Branch Rd. at Philadelphia Ave. Takoma Park 1,228 1,680
20 Columbia Pike at Fairland Rd. Fairland 1,416 1,678
21 Connecticut Ave. at Jones Bridge Rd. Chevy Chase 1,490 1,672
22 Montrose Rd. at Tower Oaks Blvd. Rockville 1,663 1,232
23 Bradley Blvd. at Wilson Ln. Bethesda 1,660 1,603
24 Falls Rd. at Maryland Ave./Potomac Valley Rd. Rockville 1,384 1,658
25 Georgia Ave. at Norbeck Rd. Aspen Hill 1,656 1,592
26 Frederick Rd. at Shady Grove Rd. Shady Grove 1,647 1,486
27 Colesville Rd. at Dale Dr. Silver Spring 1,604 1,645
28 Shady Grove Rd. at Midcounty Hwy. Derwood 1,644 1,323
29 Clopper Rd. at Waring Station Rd. Germantown 1,636 1,589
30 Montgomery Village Ave. at Stedwick Ln. Montgomery Village 1,633 1,170
31 Connecticut Ave. at Bradley Ln. Chevy Chase 1,415 1,628
32 Georgia Ave. at Forest Glen Rd. Silver Spring 1,318 1,626
33 Colesville Rd. at Sligo Creek Pkwy. Silver Spring 1,508 1,624
34 Georgia Ave. at Columbia Blvd./Seminary Ln. Silver Spring 1,520 1,624
35 Veirs Mill Rd. at 1st St. Rockville 1,610 1,475
36 Aspen Hill Rd. at Arctic Ave. Aspen Hill 1,609 1,467
37 Norbeck Rd. at Muncaster Mill Rd. Aspen Hill 1,609 1,238
38 Columbia Pike at Greencastle Rd. Fairland 1,607 1,575
39 Old Georgetown Rd. at Tuckerman Ln. North Bethesda 1,604 1,261
40 Great Seneca Highway at Quince Orchard Rd. Gaithersburg 1,602 1,547
41 Randolph Rd. at Parklawn Dr. North Bethesda 1,601 1,165
42 Democracy Blvd. at Falls Rd./South Glen Rd. Potomac 1,594 1,167
43 River Rd. at Holton-Arms School Bethesda 1,591 1,358
44 Norbeck Rd. at Bauer Dr. Aspen Hill 1,586 1,329
45 Randolph Rd. at New Hampshire Ave. Colesville 1,440 1,580
46 Layhill Rd. at Ednor Rd./Norwood Rd. Olney 1,579 1,425
47 River Rd. at I-495 Bethesda 1,579 957
48 River Rd. at Willard Ln./Greenway Dr. Bethesda 1,579 1,530
49 East-West Hwy. at Jones Mill Rd./Beach Dr. Chevy Chase 1,087 1,574
50 Colesville Rd. at Franklin Ave. Silver Spring 1,413 1,571
Data from the Montgomery County Mobility Assessment Report. CLV = Critical Lane Volume. Click on a column header to sort.

As a result, while these areas do have higher-than-average rates of foot and bike traffic and high rates of transit use, they’re not as congested as more suburban parts of the county. Just 16 of the top 50 intersections were inside the Beltway.

Not surprisingly, some of the busiest junctions are along major commuter routes like Rockville Pike, Connecticut Avenue, and Georgia Avenue. But many are on small, two-lane roads in suburban or rural communities like #4, Darnestown Road and Riffle Ford Road in North Potomac, or #46, Layhill Road, Ednor Road, and Norwood Road near Sandy Spring. These places are spread-out and far from transit, jobs, and other amenities, meaning residents have to drive a lot.

Layhill Road and Norwood Road. Image from Google Street View.

This report shows that if you build places on the assumption that people will drive everywhere, you’ll get a lot of traffic, while if you give people options, you’ll get less. Not everyone may want to live downtown, but those who choose to do so are keeping the roads clear for everyone else.