The chip-seal saga continues. Many of you have seen the current project on Hwy. 36, north of Boulder. Cherryvale, Olde Stage, and Nelson Roads are also up for resurfacing in the coming weeks. I emailed the County’s communications manager, Dan Rowland, to ask about it and here’s what he had to say:
“Chip seal is one of the most cost-effective preventative maintenance strategies we have for extending the life of pavement. It can add up to 10 years to the life of asphalt pavement, saving thousands of dollars in maintenance and rehabilitation costs. It is important to seal the entire road surface, not just the drive lanes, in order to gain the maximum effectiveness from the procedure.
“We generally try to chip seal newly paved or overlaid roads within 5-7 years. The key to chip sealing is to perform this procedure before roads are in poor condition, which is why the procedure is often applied to roads that appear to be in good condition.
This year we are utilizing a ¼-inch chip instead of the customary 3/8-inch chip, and we will be fog coating the finished chip seal. The smaller chip combined with the application of the fog coat will better fill spaces and provide a smoother finish. The new surface will not ride like pavement, but we are hopeful this new process will provide a better ride quality – particularly for cyclists – and still extend the life of our pavement investment.”
Mr. Rowland also contacted the Boulder County Road Maintenance Division Manger, who had this to say:
“Boulder County has more than 40 years of experience with the chip seal process and due to budget issues we have not been able to chip seal all of the roads we would have liked to. Because we have roads that have not been chipped we are able to compare them to like roads that have not (sic) been chipped and I can assure you we have seen accelerated pavement distresses on those roads that were not chip sealed. These distresses include potholes, alligator cracking and sub-surface settling. Just about every county in the state does chip seal as well as many of the municipalities as this is a proven and effective maintenance procedure.
“In the past we did chip seal a few roads and only did the traveled lanes not the shoulders. What we found was increased complaints from motorists and cyclists alike who felt the transition from the chipped portion to the untreated portion of the shoulder was a hazard. Bikes with small tires were affected the most as this transition was sometimes as much as 3/4 of an inch. In addition it affected road conditions and snow plowing operations in winter months.”
The above still doesn’t cite any scientific information related to chip-sealing, but it does the County has considered the impacts on cyclists and the budget.
In the meantime, feel free to contact Dan Rowland, DRowland@bouldercounty.org, to express your thoughts. Politely, people!
You might also consider running a fatter tire–it’ll smooth out the ride, resists flats, and allow you to pedal some dirt once in a while. I’m running a 33c Rivendell Jack Brown (https://tinyurl.com/26yz5fh) at the moment and I love it. I’ve pedaled to Gold Hill via the Switzerland Trail and it’s definitely doable. A little chunky on the road…but hey, so am I!
Now, just to keep things even more convoluted…here’s the latest from CDOT, with comments from Hugh Walton sprinkled throughout:
- “Dan was very forthright and sincere. He seems as though he truly cares about the quality of cycling. He rides.
- Boulder County has considered not chip sealing shoulders but does not like that solution due to differential in road surface and problems that can cause for both bikes and cars. It also is a problem for plows to a certain degree in winter time and it often misses a key cracking area where the underlying road-bed structure has been modified to add a shoulder and then paved over.
- The County is switching to a 1/4″ aggregate (pebbles) instead of a 3/8″ aggregate. This make for a smoother chip seal. In addition, after the initial overlay with chip-seal, a “Fog Seal” will be laid down on top of that. That makes it smoother still
- Dan felt that this would provide a much smoother biking surface than traditional chip-seal surfaces
- He did not address Hwy 36, but that chip seal by the state was done with a 3/8″ aggregate and I don’t know if it will be enhanced or coated with the “fog seal”. I will ask CDOT for sure on this.
- There are other techniques that improve the smoothness (and supposedly the effectiveness) of chip seal as well, including the practice of “racked in seal” (first figure below) and a “cape seal” (second figure) and I’m going to contact CDOT to see if they do this and if not, why not and whether they could use these various techniques to smooth out the road surface of the newly chip sealed section
- I don’t know why the chip sealed section of road on Hwy 36 starting about 1 mile north of Nelson road is so much smoother than the new section but I’m fairly certain it’s not because of the time frame. Perhaps they used one of the two techniques above.
- I told Dan that we’d all appreciate BCDOT’s efforts to smooth out chip sealing but that a bigger picture issue is whether in fact chip seal is effective. I told him that I could not find any true studies or evidence that strongly supported this contention and that we would push the county and CDOT for this. He indicated that he’d done such research himself about 3 years ago in order to justify the chip seal budget for the county and that there is also an expert at Colorado State who might be able to provide the information.
- I told him that anecdotally it did not seem that chip sealing did anything really and I explained why. I also explained that sometimes, such as on Apple Valley road, chip seal is done on a very poor surface that simply makes the road look better but hides serious faults in the road, thereby increasing the danger to cyclist. I told him that Olde Stage Road was in fact in this condition, having ridden it very slowly yesterday. Normally I ride it blazingly fast but yesterday I purposefully slowed down to take a very good look at the road. I asked Dan what BCDOT was going to do BEFORE chip sealing that road section and he did say that “sometimes” BCDOT fixes pot holes and big cracks but did not commit to doing that this time
- He mentioned that Longmont had stopped a chip sealing program some years ago due to budgetary constraints. Hmmmm?
