Tackling the state of our aging sidewalks

Your neighborhood sidewalk has come of age. Old age.

“Cracks, potholes, tree roots, and just old age have changed the way people are looking at sidewalks,” says civil engineering transportation professor Randall L. Guensler. “What once was a modern convenience -- getting pedestrians out of the mud  -- has become, for some, an actual hindrance to getting around.”

Changing that scenario is at the heart of a 2-year, $400,000 project that Guensler and his research team are tackling on the streets of Greater Atlanta. Funded by STRIDE (Southeastern Transportation Research, Innovation, Development and Education Center)  and the Georgia Department of Transportation, the Sidewalk Quality and Safety Assessment (SQSA) project will produce a precedent-setting database that the Atlanta Department of Public Works (DPW) officials can use to evaluate and prioritize repairs in a city that boasts more than 2,500 miles of sidewalks.

“The database we create from this project will allow the city to pinpoint the areas that are most in need of repair, but in the future could be used by anyone who wants to know the condition of a neighborhood’s sidewalks – like a homebuyer,” says doctoral student Alice Grossman, one of the researchers.

“Right now, they don’t have good data to tell them where the biggest problems are.”

And there are problems.

According to a 2010 report by the Atlanta DPW, it may cost as much as $150 million to fix the backlog of sidewalk problems in Atlanta – from missing curb cuts to fully disintegrated segments that have been broken apart by bulging tree roots and winter weather.

While the city has allotted anywhere from $50,000 to $250,000 annually to address this issue in recent years, as much as $15 million annually may be required for a sustainable a sidewalk repair and maintenance program.

In many cases, Guensler said, cyclists and pedestrians compete with each other for the same sliver of pavement. This discourages alternative forms of transportation, he noted, and does nothing for those who travel by wheelchair.

“It’s a problem that affects everyone,” said Alexandra Frackelton, a graduate student in urban planning who is part of the research group. “If people don’t want to use the sidewalks, there’s more of a temptation for them to use cars.”

While property owners who abut a sidewalk can be assessed for damaging the sidewalks, the responsibility for routine sidewalk maintenance is currently a hotly debated topic in Atlanta. Guensler believes the onus is on the municipal government.

“The sidewalk is a public conveyance and is no more a part of the homeowner’s property than the road that is adjacent to the sidewalk,” he said. “Yet, nobody asserts that homeowners are individually responsible for the repair and maintenance of adjacent roadways, fire hydrants, lighting, signage, or community parks. Responsible management of community-owned facilities is actually one of the reasons that we have local government.”

Guensler also pointed out that the need to maintain and upgrade the city’s sidewalks is getting greater as an increasing number of Baby Boomers move to urban areas for their retirement. Cracked and crumbling sidewalks do not meet ADA-requirements. And they invite lawsuits.


“It’s really the perfect storm,”  Guensler said. “Because the problem has grown over 20-30 years, due to delayed maintenance, and funds for it are just not there. At the same time, we’re seeing more and more lawsuits.”

Guensler says there may not be a perfect answer to this perfect storm, but amassing a solid database is a good start. Officials can maximize the impact of their limited sidewalk budgets by using the system to assign the highest repair priority to sidewalks that do not conform to ADA requirements and lower priority to sidewalks with simple surface roughness defects.

“This does not solve the problem of funding, but it does make it easier to allocate funds responsibly.”

The sidewalk quality assessment crew started its work by creating its own testing equipment. Working with colleagues from the College of Computing and the School of City and Regional Planning, the transportation engineering students have retrofitted several non-motorized wheelchairs with Android-programmed tablets, complete with internal video cameras, GPS, accelerometers, and gyroscopes that record the navigability of the sidewalks from several angles.

They adapted mapping and video processing tools previously used for vehicle tracking so that the system uses the GPS and video data to create GIS-based sidewalk inventories and online maps. Video processing also automatically estimates sidewalk width, records the localized presence of walkway obstructions, and visually identifies major sidewalk cracks requiring maintenance.

Check out one of the video records that the team has collected.

During the second phase of the research, teams of orange-vested graduate students, community volunteers, and paid undergraduates have been deployed to the streets of Atlanta, where they wheel these seemingly empty chairs as far as 15 miles a day.

The next step will be the analysis of additional data, which will allow them to actually rate the sidewalk safety.  The eventual result, a Sidewalk Quality Index (SQI) will help residents and the city to objectively rate sidewalks on a numeric scale showing prioritization for repairs, improvements, and replacements. Using open-source software, anyone will be able to see how their neighborhood sidewalks rate.

“Transportation professionals from around the country are very interested in what we are doing, because this data collection process could help so many communities, so many cities,” said Guensler. “We are hoping to eventually create a national research center with other university partners where sidewalk performance data can be centrally stored, analyzed, and made available for online research.”

Before they set foot on the sidewalk with their empty wheelchairs in tow, the SQSA teams reached out to a variety of governmental and community groups, including the Atlanta Regional Commission, the Neighborhood Planning Units, and PEDS, a local pedestrian advocacy group.

“People are generally supportive of us being out there,” said Guensler. “But some are not convinced that the government will be able to act upon the information given current fiscal constraints. We can’t do anything about the politics, but we can give people data.”