Shore Drive with its double yellow line
The short version
At some point, the county painted a double yellow line down the middle of Shore Drive. It probably seemed like a safety measure. It wasn't.
Traffic research from the federal government, state governments, and universities all points the same way. When you paint a center line on a quiet residential street, drivers see a road built for speed. They claim "their" lane. They pay less attention. They drive faster.
And when drivers go faster, the people walking, biking, and playing along the road are in more danger. Shore Drive isn't just for the people who live on it. It's how the whole neighborhood gets to the water, to the park, and to each other.
Here's what that looks like on a Saturday. Trucks and trailers from all over the county come through on their way to the boat ramps. Most of those drivers don't live here. They don't know which driveway the kids on bikes come out of, or that the couple walking their dog does it every morning at eight. A road that looks like a highway tells them to keep moving. A road that looks like a neighborhood tells them to slow down.
This is our home. We'd like it to be a safe place for the people who live here. That's the whole story. The details are below.
The line was never required
The federal rulebook for road markings is called the MUTCD. It says a center line is required only on busy roads carrying 6,000 or more vehicles a day. It says a center line is recommended above 3,000 a day. Below that, it says nothing at all.
Shore Drive is a two-lane street with no through traffic and no stores. It carries far fewer than 3,000 cars a day. The double yellow line was a choice, not a rule.
Lines and wide lanes make people speed
This is the part that surprises people, so here's what the research found:
- Federal Highway Administration, 2010. Narrowing roads cut crashes by 19% to 47% in three states. Narrower lanes make drivers pay attention and slow down. Wider, clearly marked lanes do the opposite.
- Federal Highway Administration, 2022. Its speed guidance says narrowing lanes "can force slower vehicle traffic" and give drivers "more time to react to pedestrians."
- National Cooperative Highway Research Program, 2024. Injury crashes in towns are tied to wider lanes and higher speeds.
- Johns Hopkins University, ongoing. On roads posted at 30 to 35 mph, wider lanes saw more crashes. The researchers think drivers "speed up and pay less attention" when lanes feel wider.
- University of Maine. Narrower streets with lower speeds have the fewest car-and-pedestrian crashes. Wider, faster streets have the most.
Take the line off, and people slow down
Other places have tested exactly this. In 2014, Transport for London removed center lines from three residential streets during repaving. Speeds dropped 5 to 9 mph, up to 13% on one street. Their report said center lines give drivers a "psychological sense of confidence" that the lane is theirs, and that removing them "introduces an element of uncertainty which is reflected in lower speeds."
A county in England found the same thing over four years: fewer speeders and fewer injury crashes. Scotland is running a nine-site study right now with early results showing "significant reductions in speed."
Here in Florida, Palm Coast and Deltona both use lane narrowing to calm neighborhood traffic. Jacksonville's "20 is Plenty" program is built on the same idea: the design of the road, not the sign, decides how fast people drive.
Why a few miles an hour matters so much
The link between speed and survival is not a straight line. It bends sharply. Here's what the AAA Foundation for Traffic Safety found for a person on foot who gets hit:
- At 20 mph: about a 90% chance of surviving.
- At 30 mph: about a coin flip.
- At 40 mph: only a 10% to 15% chance.
The Insurance Institute for Highway Safety confirmed this in 2024: a 1% chance of death at 20 mph, 19% at 35 mph, over 80% at 50 mph.
So the 7 mph drop London saw isn't small. At the speeds on Shore Drive, it cuts the risk of a pedestrian dying nearly in half.
For our older neighbors, it matters even more. AAA found that a 70-year-old hit at 25 mph faces the same risk as a 30-year-old hit at 35 mph. On a street with as many retirees as ours, the difference between 25 and 30 mph is the difference between a scare and a funeral.
Who's most at risk
Kids. They're small, hard to see, and they chase balls into the street. On a street without a center line, drivers expect children. On a street with a double yellow line, drivers expect a clear lane.
Older neighbors. Many of us walk Shore Drive every day. We move a little slower. Our bodies don't bounce back the way they used to.
Everyone with a dog, a bike, or a stroller. Which is most of us.
What we're asking the county to do
The county has spent years talking about safety on Shore Drive. The first step toward it costs nothing at all. Stop painting the line.
Want to help? The best thing you can do is show up and stay in touch. Join the list and we'll let you know when it matters.
Sources
- FHWA. Manual on Uniform Traffic Control Devices (MUTCD), Section 3B.01. https://mutcd.fhwa.dot.gov/htm/2009/part3/part3b.htm
- FHWA. Evaluation of Lane Reduction 'Road Diet' Measures on Crashes (FHWA-HRT-10-053), 2010. https://www.fhwa.dot.gov/publications/research/safety/10053/
- FHWA. Speed Management: Lower Citywide Speed Limits and Street Design (FHWA-SA-22-13), 2022. https://highways.dot.gov/sites/fhwa.dot.gov/files/2022-06/fhwasa2213.pdf
- FHWA. Traffic Calming ePrimer. https://highways.dot.gov/safety/speed-management/traffic-calming-eprimer
- NCHRP / TRB. Transportation Benefits and Costs of Reducing Lane Widths, 2024. https://rosap.ntl.bts.gov/view/dot/74632
- Johns Hopkins Bloomberg School of Public Health (Shima Hamidi). Lane Width and Road Safety Study. https://hub.jhu.edu/2022/02/08/shima-hamidi-road-width-study/
- Per Gårder, University of Maine. The Impact of Speed and Other Variables on Pedestrian Safety in Maine, 2004. https://www.sciencedirect.com/science/article/abs/pii/S0001457503000599
- City of Palm Coast. Traffic Calming Pilot Study. https://www.palmcoast.gov/traffic-calming-pilot-project
- City of Deltona. Residential Traffic Calming Handbook. https://deltonafl.gov/DocumentCenter/View/532/Traffic-Calming-Handbook-PDF
- AAA Foundation for Traffic Safety. Impact Speed and a Pedestrian's Risk of Severe Injury or Death, 2011. https://aaafoundation.org/impact-speed-pedestrians-risk-severe-injury-death/
- Insurance Institute for Highway Safety. Vehicle Height Compounds Dangers of Speed for Pedestrians, Dec. 2024. https://www.iihs.org/news/detail/vehicle-height-compounds-dangers-of-speed-for-pedestrians
- Transport for London. Centreline Removal Trial, 2014. https://velobuscotedopale.wordpress.com/wp-content/uploads/2017/07/tfl-2014-centreline-removal-trial.pdf
- Streetsblog USA. Removing Center Lines Reduced Speeding on London Streets, Aug. 2014. https://usa.streetsblog.org/2014/08/15/removing-center-lines-reduced-speeding-on-london-streets
- East Lothian Council / University of the West of England. Centreline Removal Study. https://www.eastlothian.gov.uk/info/210566/roads_and_transport/12642/projects/7
- Strong Towns. Does Center Line Striping Make Streets Safer? Oct. 2016. https://archive.strongtowns.org/journal/2016/10/31/ask-r-moses-does-center-line-striping-make-streets-safer