Any ideas for an environmentally friendly bike trail pavement?

[John Driz]

I'm working on a project to pave a 600 foot stretch of a local trail here in Missoula, MT which runs along the Clark Fork River adjacent to Teddy Roosevelts Boone & Crockett Club.  Currently the rest of the trail has been recently paved with asphalt which is creating some runoff problems.  Any ideas on an environmentally friendly pavement which would be cost effective, and smooth enough for wheel chairs?

[windrath]

Hi John -

I will check into the contact info for a fellow in Seattle who sells "asphalt" that is not made from petroleum.  When I get the info, I will post or get it to you somehow.

paul

[John Driz]

Hey thanks for your help!  Here is my email driessenart at yahoodotcom. 
I've been looking high and low for a good solution.  I came across a material called Filter Pave which is a blend of recycled glass and adhesive but heard some mixed reviews.  The material will actual filter as water passes through, but if not mixed perfectly can pop some tires creating a real hazard.

[MIBIKER]

Recycle glass is not a good idea. The Pere Marquette Rail trail in Michigan used recycle glass. After a year they resurfaced it because the glass caused lots. Tires pick up the super small pieces of glass and causes flat and it is very difficult to find the glass.  I would not want to fall on the stuff. Is it possible to use recycle tires??

[FredHiltz]

I looked at such pavements for wheelchair access to some paths in my town. We discovered a porous form of asphalt that lets water drain through it, then we learned that it gets mixed reviews. First, it breaks up during freeze-thaw cycles. Vermont paved part of I-89 with it and had trouble during the second year. It broke up so badly two years later that they quit patching it and repaved the entire stretch.

Second, some people found that dirt filled the pores after a while to the point where it was not porous enough to drain.

We settled on standard black asphalt amended with 8" PVC culverts where necessary and miniature gravel-filled ditches along both sides throughout. So far, so good, but it's only 1-1/2 years old.

Fred

[Tourista829]

John. Although filler is a good way to reduce the manufacture of asphalt, glass is not a good one. In Florida, there are glass and sand used in the road fill and it is abrasive on tire rubber. Two things you could look into. In Texas, they are having an issue with discarded tires and now use a good part of there fill with recycled tires. The ARC, Asphalt Research Consortium, are researching alternative methods for a more environmentally friendly solution. "One of their first goals is to develop so-called "cold mix" asphalts for widespread introduction into the United States. Places like Africa and India have used them for decades, and research shows they can save up to seven times the energy of their hot mix counterparts."  Considering 90% of all roads are paved with asphalt and almost the rest in concrete, this may be a possible solution. Bob

[JayH]

I know that some some running ovals are made of this rubber from recycled tires.. It has a spongely feel to it when running on. Don't know much about it or how much is post-consumer recycled tires but I know that is an option.

Jay

[John Driz]

Does anyone have a good link for more info on recycled tire pavement, cost, process, and manufacturers?  It does sound like a great option.  My only concern is patching, durability, and any harmful runoff.  I found this link which provides more insight: http://www.americantrails.org/resources/trailbuilding/recycleasph.html
The major downside is that you can only use a maximum 30% recycled rubber as an additive to the asphalt.  Not great but not so bad if it were possible with a non petroleum based asphalt as Paul suggested inexpensively

[whittierider]

I've always wondered how we could have so much pavement without it being bad for the environment, but when they slurry-sealed our alley a couple of years ago, I was astonished that within days, healthy weeds were growing up through the slurry!

[erniegrillo]

check out the Great Allegheny Passage Trail from Pittsburgh, PA  and the Montour Trail Connector.  They use crushed limestone...  It quickly settles and becomes a fine, smooth hardpacked surface. 

[paddleboy17]

I have ridden an number of crushed limestone trails.  It is cheaper than blacktop, but the rolling resistance is higher and I don't know how that affects you ADA requirements.  Runoff does not seem to be an issue.

[rvklassen]

I have ridden an number of crushed limestone trails.  It is cheaper than blacktop, but the rolling resistance is higher and I don't know how that affects you ADA requirements.  Runoff does not seem to be an issue.

Not only is the rolling resistance higher, but it can be dusty when dry, which is not friendly to drive trains.  And it is susceptible to washouts - a preventable issue with adequate engineering of ditches and culverts.   On the good side, any of these softer trail materials are more forgiving too tree roots that pass beneath them than asphalt which produces  tell-tale cracks and bumps.

[DaveB]

I have ridden an number of crushed limestone trails.  It is cheaper than blacktop, but the rolling resistance is higher and I don't know how that affects you ADA requirements.  Runoff does not seem to be an issue.

Not only is the rolling resistance higher, but it can be dusty when dry, which is not friendly to drive trains.  And it is susceptible to washouts - a preventable issue with adequate engineering of ditches and culverts.   On the good side, any of these softer trail materials are more forgiving too tree roots that pass beneath them than asphalt which produces  tell-tale cracks and bumps.

I have ridden both the trails mentioned above and agree that the crushed limestone surface, while "environmentally friendly", does have it's drawbacks.  It's rolling resistance is noticably higher than any blacktop surface, particularly when wet, and it is really dusty in the dry. 

It can be ridden on road tires and I have used a street bike with 700x23 tires but wider Hybrid or semi-slick MTB tires work a lot better. As to wheelchairs, I think it would be very difficult for them and I wouldn't want to have to push one more than a very short distance on such a surface.

[paddleboy17]

I have just returned from riding the Pine Creek Gorge in Pennsylvania.  They used crushed stone, an it makes crushed limestone look like a super highway.  Crushed stone is even dustier, and it has even bigger washout problems.