A Smarter Way to Inventory Sidewalks and Bike Lanes Across Cities

Learn how cities can automate sidewalk and bike lane inventories using AI and satellite data—faster, more accurate, and ready for planning.

Keeping track of hundreds of miles of sidewalks and bike lanes across a city is no small task. Yet accurate and up-to-date inventories of these assets are essential for safe, accessible, and equitable urban planning. Nearly 20% of traffic deaths in the U.S. involve pedestrians or cyclists, and more than half of all short trips are made by walking or biking.

Despite this, many cities still rely on outdated or incomplete methods to monitor active transportation infrastructure.

One ADA transition plan acknowledges the challenge bluntly: “it is difficult to maintain an accurate inventory of all sidewalk gaps and missing curb cuts throughout the City.” Even when audits are conducted, researchers have found that many planners still rely on manual tracing or visual checks—processes that are time-consuming, labor-intensive, and often deprioritized. As cities look to build safer, smarter networks, modern solutions are helping bridge this critical data gap.

Why up-to-date sidewalk & bike lane data matters

Complete, current inventories of sidewalks and bike lanes are essential for modern urban planning and safety initiatives. Inaccurate or outdated data can undermine efforts to build safe, accessible cities. Consider these stakes:

• Safety: Pedestrians and bicyclists account for a large share of traffic deaths. The U.S. DOT reports cyclists and pedestrians make up nearly 20% of traffic fatalities. Planners need to know exactly where sidewalks or bike lanes exist (or don’t) to identify dangerous gaps in the network.
• Equity & ADA Compliance: Federal ADA rules require accessible pedestrian facilities, including curb ramps and continuous sidewalks. City ADA plans routinely inventory sidewalks to meet legal obligations. But it’s hard to track changes: as the El Paso ADA plan notes, “it is difficult to maintain an accurate inventory of all sidewalk gaps and missing curb cuts throughout the City”. Without automated data, marginalized neighborhoods may slip through the cracks.
• Vision Zero and Safety Goals: Many jurisdictions have adopted Vision Zero programs to eliminate traffic deaths. Achieving those goals demands prioritizing bike lanes, crosswalks, and sidewalks in dangerous corridors. In fact, experts stress that “bike and pedestrian planning is integral to achieving Vision Zero goals” by targeting infrastructure improvements. Accurate asset inventories are the foundation for this targeted planning.
• Mobility & Health: Walking and cycling are key modes of transportation (over half of trips under 3 miles in the U.S. are on foot or bike) and vital for healthy communities. Gaps in the network force people into traffic or prevent trips entirely. Modern planners need up-to-date data to perform “sidewalk gap analyses” and ensure the network actually connects (for example, identifying where sidewalks abruptly stop or do not exist).
• Funding & Planning: Billions of dollars in federal and state grants are targeted at sidewalk and bike lane projects, but agencies must justify projects with solid data. In fact, a U.S. DOT analysis estimates about $7 billion in unmet needs for bike/pedestrian infrastructure nationwide. With Urban SDK’s data, agencies can pinpoint those needs precisely and make a stronger case for funding.

In short, complete and current sidewalk/bike lane inventories underpin every major transportation and safety initiative. But how do we get there?

Limitations of traditional methods

Historically, cities have relied on manual surveys and audits to document sidewalks and bike lanes. These methods have serious drawbacks:

• Time-consuming field work: Traditional inventories require teams to walk or bike every block, recording measurements and conditions by hand. Surveys are slow and expensive – one study found typical sidewalk inventories cost $86–$826 per road-mile surveyed. Even in small cities, costs can climb into the tens of thousands, pulling resources away from other priorities.
• Fast obsolescence: By the time a manual survey is finished, parts of the city may have changed. New sidewalks get built, old ones deteriorate, curb ramps get replaced – and officials often fall behind. As we saw, a city report laments that keeping an inventory current is “difficult”. In practice, many agencies simply go without complete data.
• Limited coverage and detail: Even with field crews, surveys often miss things. Some cities rely on crowdsourced or street-view audits to tag curb cuts or missing sidewalks, but these approaches capture only what’s visible and often omit important measurements (for example, street trees or precise widths). Incomplete data can lead to blind spots in planning.
• Labor-intensive data processing: Collected data often lives in spreadsheets or outdated GIS layers. Combining, cleaning, and analyzing these datasets is tedious. As one expert put it, many agencies still depend on “manual auditing and tracing” of pedestrian assets, which is so labor-intensive that it’s often skipped entirely.
• High costs vs. limited use: Research shows sidewalk inventories typically consume “not more than 1% of the responsible department’s budget”, yet still represent a non-trivial expense. For many cities on tight budgets, the manual approach doesn’t scale – especially when repeated updates are needed.

In short, relying on legacy surveys is a slow, costly, and error-prone way to manage thousands of street segments. That’s why we built a better approach.

Our smarter, scalable approach

At Urban SDK, we automate sidewalk and bike lane inventories using satellite imagery, machine learning, and GIS analytics. Our platform detects and measures pedestrian and cycling infrastructure across entire road networks without field crews, delivering data that’s precise, current, and ready for planning. Key features of our solution include:

• AI-driven feature extraction: We use advanced computer vision and deep learning to scan high-resolution aerial and satellite imagery for sidewalks, bike lanes, crosswalks, curb ramps, and related assets. This means that we can create.a full pedestrian infrastructure inventory, which would normally take surveyors months, in a fraction of the time
• Comprehensive, city-wide coverage: Unlike piecemeal or crowdsourced efforts, our platform covers all streets in your jurisdiction, from major arteries down to neighborhood lanes. We analyze every road segment in a single workflow, so you never miss a block.
• Rich 3D road attributes: Our Roadway Characteristics Data includes detailed geometry for each street. For example, we quantify the number of lanes, road width, and median or boulevard dimensions, and crucially sidewalk and bike lane details. This includes the presence of sidewalks/bike lanes, their widths, and even surface type. Planners get all the attributes of a field survey, all derived from aerial data.
• Easy GIS integration: We deliver data in standard GIS formats so that transportation and public works teams can import it into their existing systems. Agencies can also merge Urban SDK data with their local surveys to fill gaps. For example, our platform lets you overlay city-collected curb ramp or condition data on top of the automatically-generated sidewalk layer, creating one unified inventory.
• Validated accuracy: Our methods are aligned with cutting-edge research. For instance, a 2024 study shows combining mobile LiDAR and satellite imagery with AI (the SAM model) creates “a scalable pedestrian infrastructure inventory approach” that benefits city managers and people with disabilities. Similarly, a recent real-world use case saw an AI mapping platform help Contra Costa County extract bike lanes, sidewalk locations, and road widths from aerial images for Vision Zero planning. We deliver that level of detail to your fingertips, without the delays.

Key benefits

By leveraging these technologies, Urban SDK users enjoy huge time and cost savings. There’s no need to hire survey crews or analyze terabytes of imagery manually. We replace hundreds of hours in the field with automated processing. A

s one city engineer put it, having this information “at our fingertips” means far fewer trips to collect data, letting staff focus on solutions instead of spreadsheets. Moreover, the data quality is as good as – if not better than – a human survey. We catch features even under trees or at night that older systems miss, and we provide precise measurements down to the foot.

Use cases: Planning, Compliance, and Safety

Our sidewalk and bike lane inventories power a wide range of municipal initiatives. Here are just a few examples:

• ADA Compliance & Equity: Identify missing curb ramps or sidewalk gaps across neighborhoods to support ADA transition plans and ensure equitable access.
• Vision Zero and Traffic Safety: Overlay sidewalk and bike lane maps with crash data to target high-risk corridors and prioritize safety interventions.
• Mobility and Active Transportation Planning: Conduct sidewalk gap analyses to design walkable and bikeable networks. Ensure bus stops, bike-share stations, and safe routes to school align with real-world infrastructure.
• Infrastructure Funding & Grant Support: Justify funding requests with precise data on asset gaps, coverage, and condition. Demonstrate project readiness and need with confidence.
• Public Works and Asset Management: Plan maintenance and repairs with data on sidewalk surface type, condition, and continuity. Coordinate bike lane improvements and street resurfacing.

In all these cases, the same up-to-date data serves multiple departments—from planning to public safety—saving time, money, and effort.

At Urban SDK, our platform and Roadway Characteristics Data help cities unlock smarter infrastructure decisions. We combine satellite imagery, AI, and easy-to-use tools to make sidewalk and bike lane inventories faster, more affordable, and far more actionable.