Is there a compliant curb ramp out there?

Michele S. Ohmes
ADA/Disability Specialist
City of Kansas City, Missouri
Member, APWA Facilities and Grounds Committee

Even though I am writing about inspecting curb ramps I first want to get across another consideration. To borrow from an airport expression, "If you see one airport, you see one airport." The same goes for curb ramps. Curb ramps fall into the descriptive categories of blended transition, combination, diagonal, directional, perpendicular, parallel, projected, and radial, at-grade approaches and islands; however, we all know that every location is unique to the usage, surroundings, buildings, geometrics of the intersection, crossing pattern, street slope, etc. Too often sidewalk curb ramps are not thought out before "slapping" them into a corner, mid-block crossing or parking lots. Many are round pegs being forced into a square hole.

The catchall design at intersections is the diagonal ramp that actually requires two actions for the user: (1) step out into the street at a forward diagonal angle, and then (2) change directions to actually cross in the direction they need to go. For wheelchair users and someone pushing a baby stroller increased danger exists since they must extend into the traffic much farther than a standing person. The walking pedestrian can choose to step over the curb to take a more direct approach; however, that is not so easy for devices with wheels.

As an inspector several considerations should be reviewed. The first is whether the design of the curb ramp is the best answer for the corner or location where it has been installed. I realize that if the curb ramp meets all the specification guidelines you might not be able to demand it be removed, but you do have a perfect opportunity to explain how a different type of curb ramp could have been installed for the benefit of the users. Secondly, is the installed curb ramp compliant? This article is to provide you with some tools for examining the curb ramp. Thanks to the wisdom of others, along with my own experiences, the following information should give you some definitive insights.

1. The obvious first tool is the "Smart Tool Level" which measures the slopes and produces the results by percent, degree, or pitch. I have the sensor and two-inch models. For some, having all three sizes is helpful since these tools cover areas on very short restricted spaces to long pedestrian ramps including stadium ramps, with each size addressing specific circumstances. Of course, the Smart Tool Level is the easy part; understanding the ramp components is important to be able to critique and find solutions for building a compliant curb ramp.

2. The second tool is picking up an older manual wheelchair and giving it a try. Believe me, your approach will change if you have to try to use a curb ramp you are inspecting. Nothing gives me converts to the seriousness of designing a safe curb ramp more than doing a walkabout with the designers/engineers with a wheelchair for them to test-drive the curb ramps, walks, etc.

3. A graphic that Mike Whipple (formerly with the City of Sacramento, now an independent ADA consultant) put together that labels the actual components of a ramp as follows:

4. A curb ramp inspection form that Mike Ross (Assistant City Engineer, City of Overland Park, KS) and his staff have designed in an Excel worksheet. There is not enough space in this article to include it. However, should you want a copy you can e-mail Mike at Thanks to Mike's commitment to excellence, an approach that is now in place in Overland Park is that all curb ramps are completely designed by the engineers with all dimensions and grade levels shown. This takes the guesswork away and provides contractors with the details necessary while providing the governmental entity the ability to demand reworking of a curb ramp not installed according to the design. Expecting contractors to make the best decision onsite is a mistake that everyone pays for in the end.

Some of the most common errors on curb ramps are:

  1. Excessively steep ramps. I have measured the slopes of ramps to as much as 18% slope with only a 24" width at the top of the ramp leading onto the sidewalk.

  2. Cross slope is greater than 2%.

  3. Warping is present due to flared sides and turning approaches to corner ramps.

  4. Side flares are rounded in such a way that they decrease the required width of the actual ramp and cause a slipping hazard.

  5. Ramps leading into drainage grates.

  6. Ramps that are protected by street furniture or grass can have a straight edge versus sloped sides. In fact, this is the preferred method by the blind and others.

  7. A vertical level change exists from the street onto the curb ramp. (NOTE: If a ramp is installed before road resurfacing is completed it is imperative to somehow drop some asphalt or some type of transition solution at the ramp so users are not forced to face 3-4" vertical level changes until the road improvements catch up to the ramp improvement.)

  8. Rounded lazyback curbs are considered compliant. This is a dangerous assumption that leads to serious problems.

  9. Detectable warnings are not installed. Some are still using groove curb ramps instead of the required truncated dome detectable warnings.

  10. Detectable warnings installed at driveways. Unless the driveway is signalized, detectable warnings in these locations cause confusion for the blind. It suggests they are crossing an intersection.

  11. Curb ramps without proper drainage result in a buildup of debris, sludge, and water.

  12. Islands with forced curb ramps when a simple cut-through would be safer and less confusing (addressed later in this article).

  13. Using diagonal curb ramps when a directional ramp would be safer and prevent a misleading message that there is a bidirectional crossing. Inspectors, please do everything you can to influence contractors to change this dangerous practice.

By the way, the recently published Public Rights-of-Way Guidelines Draft does address the question of detectable warnings at the rounded directional sidewalk ramp. See the advisory below from the Guidelines Draft, page 12:

Detectable warnings provisions in this draft have also been clarified with respect to their permitted setback from the grade break marking the face of a curb. One corner of the detectable warning must be within 205 mm (8 in) of the grade break; no other point on the leading edge of the detectable warning may be more than 1.5 m (5 ft) from the grade break. (R304.2.1)

The treatment for crosswalk medians and islands, including an advisory that should help designers and inspectors to simplify the design, is also addressed in the same draft on page 39 as follows:

R305.4 Medians and Pedestrian Refuge Islands. Medians and pedestrian refuge islands in crosswalks shall comply with R305.4 and shall contain a pedestrian access route, including passing space, complying with R301 and connecting to each crosswalk.

R305.4.1 Length. Medians and pedestrian refuge islands shall be 1.8 m (6.0 ft) minimum in length in the direction of pedestrian travel.

Advisory R305.4.1 Length. The edges of cut-throughs and curb ramps are useful as cues to the direction of a crossing. This should be considered when planning an angled route through a median or island. Curb ramps in medians and islands can add difficulty to the crossing for some users. There are many factors to consider when deciding whether to ramp or cut through a median or island. Those factors may include slope and cross slope of road, drainage, and width of median or island.

R305.4.2 Detectable Warnings. Medians and pedestrian refuge islands shall have detectable warnings complying with R304 at curb ramps and blended transitions. Detectable warnings at cut-through islands shall be located at the curb line in-line with the face of curb and shall be separated by a 61 cm (2.0 ft) minimum length of walkway without detectable warnings. Where the island has no curb, the detectable warning shall be located at the edge of roadway. See the diagram at left.

Alternate paths are a major problem I encounter endlessly when sidewalks, curb ramps and street construction take place. All too often inspectors, project managers and supervisors are not enforcing this necessary requirement. The following directive from the PROW Draft, page 26, once again clarifies what is already required in the 1990 ADA guidelines:

R205 Alternate Pedestrian Access Route. When an existing pedestrian access route is blocked by construction, alteration, maintenance, or other temporary conditions, an alternate pedestrian access route complying to the maximum extent feasible with R301, R302, and Section 6D.01 and 6D.02 of the MUTCD (incorporated by reference; see R104.2.1) shall be provided.

Advisory R205 Alternate Pedestrian Access Route. Same-side travel is preferred because it does not increase pedestrian exposure and risk of accident consequent upon added street crossings. A route that uses vehicle lane width may be shorter, safer, and more usable than one that requires two street crossings, even if the roadway surface is imperfect. Part 6D.01 of the MUTCD requires alternate routes to provide the best elements of accessibility provided in the pedestrian circulation route before its disruption.

Hopefully, the above information will help you in considering your curb ramps and inspecting them. I also hope you will download the Public Rights-of-Way Guidelines Draft from the Access Board site. It has information that should help you to view the public rights-of-way system as a whole and understand the reasoning behind the suggested regulations the Access Board has produced. A very positive piece of information is how the Access Board has worked in coordination with other standards already in place in order to decrease confusion and give weight to the family of standards trying to address access for all as a unit versus differing views and demands. Good luck and please realize that access for all with safety should be your end goal.

Michele Ohmes can be reached at (816) 513-2533 or Contributors to this article include Mike Ross, P.E., Assistant City Engineer, City of Overland Park, Kansas, who can be reached at (913) 895-6038 or; and Mike Whipple, Consulting Partner, ADA Resource Associates, Inc., who can be reached at (916) 991-0107 or

The Institute of Transportation Engineers website ( has the articles and presentations submitted at their Curb Ramp and Intersection Wayfinding Workshop that includes presentations by Mike Ross and Mike Whipple, plus many others including Janet Barlow, Certified Orientation and Mobility Specialist, on wayfinding for the blind. It is an excellent source for information on their research and this workshop.