In the small world department, it turns out that the VP of the company giving the presentation is the brother of one of my fellow neighborhood activists in NW (which I didn’t discover until several days after the presentation).
I was fairly impressed. It seems like an environmental win-win in situations where tree roots would have you replacing concrete every few years. We went through this in front our house last year, where we have some Sweet Gum trees in the planting strip.
The basic idea is that you can maintain tree roots by removing the sidewalk panels, trimming the roots, then replacing the panel. You can also notch the panels or go to a thinner panel if you don’t want to modify the root.
A side benefit, this system is semi-water permeable (through the seams between panels) which has the dual benefit of reducing stormwater runoff and also apparently promoting less agressive root growth, since the tree does not have to work so hard to find water.
And the rubber surface has pretty good traction.
I did ask the rubber allergy question, and got the same answer discussed in the comments in the previous post, that the tire rubber recycled into these panels does not contain the rubber molecule that causes most alergies. Also, the resin that binds the rubber provides some encapsulation. I don’t know if this covers 100% of those sensitive to rubber, but there is also the fact that similar technology has been used in playground tiles for some time.
There were folks in attendance from both PDOT and Portland’s Urban Forestry office. I fired off a note to Sam Adams suggesting that Portland should do a pilot and he replied that he was aware of the product, having read about it in the Wall Street Journal.
So perhaps we’ll have a rubber sidewalk somewhere in Portland soon…
On the downside, the distribution network is still relatively immature, so a homeowner wanting to use this stuff is probably not going to find a contractor who has access to it. There may also need to be some modifications to building codes before it’s legal (don’t know for sure).