Ask a transportation planner in almost any mid-sized city what the worst block on their commercial corridor looks like on a Tuesday afternoon, and the answer is usually the same: a double-parked delivery van, a ride-hail pickup blocking the bike lane behind it, and a loading zone sign nobody has updated since before the pandemic pushed half the block’s restaurants into permanent outdoor dining. The curb has always had more demand on it than space to satisfy that demand. What’s changed over the past two years is how much of that demand is now digital — routed by apps, scheduled by delivery platforms, and increasingly invisible to the city agency responsible for managing the physical space underneath it.

That mismatch is exactly the problem the Open Mobility Foundation’s (OMF) Curb Data Specification was built to address, and this month the organization’s board formally approved version 1.0 of the standard. For planners who have been watching curb-data efforts develop for the past few years, the release is less a surprise than a milestone — but it’s a milestone worth understanding, because it changes what’s actually possible for a city trying to manage loading zones with something better than a clipboard and a parking enforcement officer’s memory.

What Is the Curb Data Specification, Exactly?

CDS is a data standard, not a piece of software a city buys off a shelf. It defines a common, machine-readable way to describe three things: what a curb segment is and what’s allowed there, what’s actually happening at that curb segment in real time or historically, and how to calculate standard metrics — like dwell time and occupancy — from that activity data.

In practice, the specification is organized around three APIs:

  • The Curbs API lets a city digitally publish its curb locations and the regulations attached to them — what’s allowed, for which vehicle types, during which hours.
  • The Events API provides a standard format for transmitting real-time and historical commercial curb activity — a delivery vehicle arriving, a ride-hail pickup starting, a loading session ending.
  • The Metrics API defines common calculation methods for turning that raw event data into comparable statistics, so one city’s dwell-time figure means the same thing as another’s.

The specification has been in development for more than a year, coordinated through OMF’s Curb Management Working Group, which has drawn contributors from more than 70 public agencies and curb-related technology companies. That breadth matters: a data standard is only useful if enough of the parties generating and consuming curb data actually agree to use it, and CDS was deliberately built as an open, city-governed alternative to proprietary curb-data formats controlled by any single vendor.

Why Loading Zones, Specifically?

Curb management covers a lot of ground — transit stops, bike lanes, accessible parking, passenger pickup — but CDS 1.0’s most immediate use case is commercial loading. That’s not an accident. Loading zones are where the practical pain is most acute right now, for a fairly specific reason: freight and delivery demand has grown faster than most cities’ loading-zone inventories have, and unlike passenger parking, loading-zone misuse tends to spill directly into travel lanes and bike lanes rather than just annoying the driver looking for a spot.

Several cities are already moving to build CDS-based approaches specifically around loading. Philadelphia is folding the specification into its planned Smart Loading Zone pilot, which will test software that gives delivery drivers real-time availability and reservation information for loading spaces rather than making them circle the block or double-park while they wait. Seattle’s transportation department has begun publishing its loading-zone data in CDS format. San Francisco is building a broader digital curb program through its municipal transportation agency, and other cities — including Omaha, San Diego, Minneapolis, Miami, Washington DC, Los Angeles, and Pittsburgh — are at varying stages of adopting or piloting the tool. OMF describes more than two dozen cities and companies now using or planning to use CDS.

What Actually Changes for a City That Adopts CDS?

It’s worth being precise about what a data specification does and doesn’t do on its own. Publishing curb data in CDS format doesn’t automatically fix a congested loading zone — a city still has to decide on the underlying policy, whether that’s dynamic pricing, time-based reservations, or stricter enforcement. What CDS changes is the plumbing underneath those policy decisions.

Before a common specification, a city that wanted to let a private curb-management vendor or a delivery platform see its loading-zone regulations and availability had two options: negotiate a bespoke data-sharing arrangement with each individual company, or not share the data at all. Neither scales. A city with one proprietary integration per vendor ends up locked into whichever companies it signed early agreements with, and switching vendors later means rebuilding the integration from scratch.

With an open specification, a city publishes its curb data once, in a standard format, and any company that wants to consume it — a delivery platform routing its drivers, a curb-management software vendor building an occupancy dashboard, a research group studying loading patterns — can do so without a custom integration. That’s the same logic that made GTFS (General Transit Feed Specification) valuable for transit agencies a decade earlier: the value isn’t in any single feature, it’s in not having to build the same integration repeatedly.

Is This the Same as the Mobility Data Specification?

Not quite, though the two are related and maintained by the same organization. The Mobility Data Specification (MDS), which OMF has maintained since 2019, was built primarily to help cities manage shared micromobility fleets — scooters, dockless bikes, and similar services — by giving cities visibility into vehicle location, trip data, and fleet compliance.

CDS addresses a different, though adjacent, problem: not the vehicles moving through the city, but the physical curb space itself and the rules governing who can use it and when. A city could reasonably run both specifications side by side — MDS to manage a scooter-share program’s compliance, CDS to manage the loading zones and curb regulations those scooters and every other curb user have to navigate. Some of the technical architecture and governance lessons from MDS’s rollout appear to have directly informed how CDS was structured.

What Should a Planner Actually Do With This Right Now?

For a planner whose city hasn’t touched curb data specifications yet, CDS 1.0’s approval is a reasonable trigger to start evaluating, not necessarily to commit. A few practical starting points:

Audit what curb regulation data your city actually has in machine-readable form today. Many cities’ loading-zone regulations exist only as GIS point layers, PDF sign inventories, or — in a meaningful number of cases — institutional knowledge held by a handful of long-tenured staff. Before adopting any data specification, a city needs to know how much of its existing regulatory information would need to be digitized from scratch versus simply reformatted.

Identify the highest-friction corridor first, rather than trying to digitize citywide on day one. The cities furthest along with CDS adoption generally started with a specific pilot — a single commercial corridor or a defined loading-zone program — rather than attempting a citywide rollout immediately. That scoping choice makes the maintenance burden manageable and produces a concrete case study for the next budget cycle.

Treat data governance as a policy decision, not just an IT question. Deciding who can access a city’s curb data, at what level of granularity, and under what terms is a public-policy choice with real stakes — a city that structures its data-sharing agreements around one commercial partner’s preferences risks building an inventory that serves that partner’s use case at the expense of the full range of functions a curb serves. NACTO’s guidance on curb management has long emphasized that curb space serves competing public functions — transit, deliveries, accessible parking, and public space among them — and that framing is a useful check on any technology rollout that risks optimizing for a single use case.

Frequently Asked Questions

What is the Curb Data Specification (CDS)?

CDS is an open data standard, maintained by the Open Mobility Foundation, that lets cities digitally publish curb regulations and locations, transmit real-time or historical curb activity data, and calculate standardized metrics like dwell time and occupancy — all in a common, vendor-neutral format.

Which cities are using the Curb Data Specification?

More than two dozen cities and companies are piloting or planning to adopt CDS, including Philadelphia, Seattle, San Francisco, Omaha, San Diego, Minneapolis, Miami, Washington DC, Los Angeles, and Pittsburgh. Adoption stages vary widely, from early piloting to active data publication.

How is CDS different from the Mobility Data Specification (MDS)?

MDS, also maintained by OMF, primarily governs shared micromobility fleets like scooters and dockless bikes. CDS instead standardizes data about the physical curb itself — its regulations, availability, and usage — making the two specifications complementary rather than overlapping.

Does adopting CDS require buying new sensors or hardware?

No. CDS is a data format, not a hardware requirement. A city can publish curb regulation data in CDS format using existing GIS and permitting records; sensors, cameras, or connected-vehicle data can enrich the real-time Events API layer later, but they aren’t a prerequisite for initial adoption.

Why are loading zones the focus of early CDS pilots?

Loading-zone misuse — double-parking, blocked bike lanes — creates safety and congestion problems that spill beyond the curb itself, and freight and delivery demand has grown faster than most cities’ loading-zone capacity. That combination has made loading zones the highest-urgency, most concrete use case for early adopters.

The Open Mobility Foundation maintains the current published version of the Curb Data Specification, including implementation guides and city case studies, at openmobilityfoundation.org. For broader context on how curb space is allocated across competing public uses, see NACTO’s Curb Appeal curbside management guidance.