Philadelphia’s sidewalks are in such poor condition that they violate federal law that protects people with disabilities, a federal lawsuit filed Monday claims.

“Philadelphia’s failure to create and maintain accessible paths of travel has made it difficult — and, at times, impossible — for me to go to work, school, and church, and has prevented me from being able to fully experience life in Philadelphia with my family,” Liam Dougherty, one of the plaintiffs, said in a statement.

Four people with disabilities and three advocacy groups filed the suit in U.S. District Court for the Eastern District of Pennsylvania on behalf of the city’s estimated 186,000 people with mobility limitations or blindness.

The suit contends that the city has allowed sidewalks to reach a dangerous state of disrepair, repaved streets without including Americans With Disability Act-compliant ramps, and has been indifferent to obstacles that a person in a wheelchair cannot get around. The city has failed to obey the ADA and a 1977 law requiring that streets be accessible, the suit says. It seeks to compel the city to evaluate the condition of its sidewalks and develop a plan to make them functional for people with disabilities.

City officials have not yet seen the suit, an administration spokesperson said, and would consider its defense after reviewing it.

People in wheelchairs or with vision impairment must navigate a daily labyrinth in traveling the city’s streets, according to the suit, and the consequences of running into an obstacle can be humiliation and injury.

In the suit, Dougherty described swerving his scooter out of the path of a pedestrian near City Hall, only to have it catch on a crack or bump, throwing him from the vehicle and causing a head injury that needed treatment at a hospital.

On another occasion in West Philadelphia, it says, Dougherty’s wheelchair tipped over on one side on uneven pavement. He lay in the street for 10 minutes before a person came along to help him right his 250-pound chair.

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Another plaintiff, Tony Brooks, described toppling his wheelchair on several occasions because curb ramps in the sidewalk were too steep. Last year, he was on Broad Street crossing John F. Kennedy Boulevard near City Hall and his chair flipped backward as he tried to navigate up a ramp. His elbows and wrists were scraped, and his elbows hurt for months, the suit says.

The ADA dictates how curb ramps should be designed, but Philadelphia’s remain inconsistent, creating a major problem for people with disabilities, the suit states. Fran Fulton, who is blind, described feeling as if she’s going to fall forward when she encounters one of the steep ramps to the street, and is challenged by others that lack textures that alert her she has reached an intersection.

Even when the sidewalks are properly designed and maintained, other obstructions can force people to turn back and find another route, the suit states. It faulted Philadelphia for failing to enforce parking laws that should keep cars off sidewalks or crosswalks. Street vendors, sidewalk furniture, trash cans, and construction sites all contribute to sidewalk clutter. In the winter, inconsistent snow removal adds another layer of difficulty. The people named in the suit resort at times to riding wheelchairs in bike lanes to avoid the difficulty of traveling on the sidewalk.

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This is not the first time Philadelphia’s sidewalk quality has been the subject of legal action. In 1993, a federal court ordered the city to install appropriate curb ramps on every city street, but in 2014, according to the suit, the Streets Department told two of the advocacy groups participating in the suit, Philly ADAPT and Disabled in Action of Pennsylvania, that it would upgrade curb ramps to be ADA-compliant only upon request, rather than automatically doing the work during repaving.

The city estimated then that almost 72,000 curb ramps needed to be improved, but with a budget of $3.2 million a year for the work, it would take 170 years to get to them all.

“For years, we have been urging the city to fix its inaccessible sidewalks," said Thomas Earle, chief executive of Liberty Resources, the third organization participating in the suit. “It’s disappointing that so long after the passage of the ADA, Philadelphia still violates the civil rights of people with disabilities.”