ADA Sidewalk Grades 3

[martin888888]

We are building a 200' driveway to a new pump station where an existing paved trail is that was constructed to be ADA compliant. The new 15' wide driveway will be utilzied as this section of the trail. The driveway however has a 7.5% longitudinal grade to it. Becasue this is a paved driveway with no ability to create landings every 30', would a 200' driveway at 7.5% be considered ADA compliant when it also doubles as a sidewalk?

 

[Pinwards]

In short, no. ADA paths have to be 5% or less. Anything greater than 5% is considered a Ramp, and then requires max. slope of 1:12 (8.3%) with 30" max rise between landings. You may have to find room adjacent for the ADA path and do a series of ramps/landings.

 

[CivilEngAus]

Does the road/driveway need to be ADA compliant? if so then you either need to provide an alternative complainant path or make the driveway longer (introduce a curve etc) so you can make it ADA compliant.

 

[BUGGAR]

I once saw a ramp that obviously had no room for landings. The adjacent railing had a hook device to hold wheelchairs while the user "rested".

 

[ACtrafficengr]

Could you build a sidewalk with landings alongside the driveway/path? Given the speed that cyclists and skaters might attain in the downhill direction, separating foot and wheeled traffic is probably a good idea. I've seen it done on heavily used paths.

 

[Twinkie]

You definitely need to make this work, can you switchback the driveway some??

 

[martin888888]

I put a 12' multiuse path next to the driveway with railings on both side for the entire length. Thanks for the responses.

 

[civilman72]

So you went with ramps along with the railing? Railing with no ramps is not ADA compliant.

Also, not sure if you purposely used the word "trail," but I believe there are different standards for ADA compliant trails vs. sidewalks.

 

[martin888888]

It is a 12' wide multi use pathway that extends from an artierial to a trail system. Used 8.33% max grade with many 5' landings with a 36" railing along both sides the length of the 8.33% grade.

 

[civilman72]

Sounds right. One other note, and curious to hear other's thoughts:

I would recommend you not design this ramp at exactly 8.33%. Maybe shoot for 8.1%-8.2%. It's what I do because I have heard stories of engineers being pulled into ADA lawsuits by contractors that claim, by the engineer designing to the maximum allowable design grade, the contractor was given no latitude for construction tolerances. As an example, if concrete placement occurs during high winds it can affect the concrete surface and final grades. These minor irregularities in the surface are usually negligible in most instances, except when you need to meet a 2.00% maximum cross-slope.

 

[TomDOT]

The perfectly good sidewalk near my house had to be entirely ripped up and replaced when the road was redone, because of a cross-slope varying up to 2.1%

 

[ACtrafficengr]

TomDOT, there are polymer cement products that are used to resurface sidewalks, among other things. EnduraBlend is one. I would have looked into whether they could correct the 0.1% deficiency without full reconstruction.

 

[TomDOT]

Unfortunately I wasn't part of the project, that was the explanation the city gave me when I called. Ripup was already in progress.

Thanks for the brand name - I was aware of the products in general for overlay, but haven't used any.

 

[CivilEngAus]

Ripped up because the slope was 0.1% higher than it should have been? Even if the footpath was 4m wide then that is only 4mm and well within surveying tolerances.

In Australia 2.5% crossfall is the limit for accessibility compliance, while maximum 5% for longitudinal fall also.

 

[TerryScan]

We design a 1.5% cross slope for ADA paths to allow for construction variability.

 

[civilman72]

To CivilEngAus: You clearly have not dealt with the ADA Nazis that exist here in the States. Starts with all the litigators & ambulance chasers and trickles down from there.

I've probably mentioned this in previous threads, but where I live and design ice buildup and drainage are huge issues. Every ADA parking space I have designed to code has significantly more ice build-up than any other parking spaces throughout the parking lot. But I'm can't use common sense and engineering expertise to improve the safety of these ADA parking spaces for fear of a lawsuit.

 

[brandonbw]

The first time I designed a parking lot my manager told me his story of designing one wrong. ADA people go searching for new projects to check grades and if its wrong, rip the whole thing out. Everyone we work with says to stay under the max grades.

I try to design parking spaces and pathways at 1% to be on the safe side. Remember to check the 2% max in all directions. Really bad design, but what can we do. One City around here has been putting in new ADA crosswalk ramps and when we go to design a new project they say the new ramp is not ADA compliant so we must rip it out and redesign a new one.

B+W Engineering and Design | Los Angeles Civil Engineer and Structural Engineer

http://bwengr.com