This blog is about streets and yet we rarely talk about pavements, the road surface itself. The most common materials are bituminous asphalt and concrete, with asphalt more common on low volume local roads and concrete on higher volume freeways. The general reputation is that concrete is stronger and longer lasting but more expensive and more difficult to construct and takes longer to set.
For a brief window in the late 2000s, concrete actually had a price advantage, which explains the surface for the Marq2 project in Minneapolis. They have other properties and claims made about them. For details on the pavement wars see ConcreteIsBetter.com and AsphaltIsBest.com (seriously, visit their sites, then come back (better yet, visit their sites from 10 or 12 years ago at archive.org (concrete) (asphalt)). Grammatically, if there were only two choices, the concrete folks would be more accurate. However, there are more than two choices.
A third choice is plank roads. These were once common (in the 1840s and 1850s) when forests were still virgin and it was an improvement over dirt, and more cost effective, were it to last. Sadly it did not last. To recall the days of plank roads the Mill City Museum had a plank section installed just outside on West River parkway. Recalling the earlier experience with plank roads, it too rotted before its time, and the other disadvantages (rough surface compared to asphalt) led to it being pulled out on the auto path, though it remains for the bike/walk path.
A fourth choice is brick. Fans of the Woonerf, as I have been since reading Streets Ahead, know that many neighborhood streets in the Netherlands have either retained or been restored to a brick or cobblestone surface. This encourages vehicles to slow down and connects the walking, playing, parking, and driving surfaces into one. There are many designs.
But this is Minnesota, we can’t have brick-clad Woonerf here, can we?
Yes, yes we can. Once our roads were brick too. The vernacular design differs with the local Midwest environment, but the underlying logic remains the same.
In many places, the asphalt is simply laid over the brick. (How many, I don’t think anyone knows, as the records, if they remain, are on paper in boxes at an archive.) In some places they have been uncovered. Some examples from St. Paul are below. In some places, like some streets and alleys in the Minneapolis Warehouse District, they were never covered.
While snow and ice are harder to clear from brick than say asphalt, that too is a traffic calming measure. And there is no requirement that on residential streets snow be plowed to the surface. A compacted snow pack over residential streets will help preserve the pavement compared to scraping them with metal blades.
The merits of respective building materials can be argued, but eventually, about the time we have flying cars and real hoverboards, the more attractive brick will again dominate asphalt and concrete for residential and shopping streets. In the meantime, we can prepare for that day and try to resurface and uncover more and different road materials to help create better looking neighborhoods and living streets for people.
“A compacted snow pack over residential streets will help preserve the pavement compared to scraping them with metal blades.” – um, compacted snow eventually freezes into a layer of ice. That’s not safe for anyone.
When I was younger the streets were never plowed to bare pavement. Nobody seemed to have problems driving on them. They just slowed down. The fact that studded tires were legal then might have had something to do with it, but I never had studded tires and had no problems.
I thought studded tires were only legal (or at least widely available) in Minnesota for a couple years before they were banned?
The Nordic standards for bikeway maintenance also call for leaving a compacted snow pack that is raked periodically if it becomes too hard packed. But like your comment suggested, the freeze-thaw cycles we have here don’t create a very pleasant surface over time.
To take the long view, concrete and asphalt were also competitive enough in price near the beginning of the street paving program in the 1960s that Minneapolis opted to use both.
I disagree that the plank road on W. River Parkway rotted. I used it many times and still use the wood bike-foot portion. It was pulled for other reasons, including the pop-up of the bolts fastening the planks. Yes wood rots eventually, but it hasn’t as of yet. One would think that planks made from recycled plastic, similar to those used in park benches and picnic tables, would serve the purpose if they could be made with enough strength and a high enough coefficient of friction.
My recollection of brick when I’d sleep over at my grandmother’s house on Grand Avenue, is that it is a relatively noisy surface. The ones I’ve seen in Mpls have deeper wheel ruts than other surfaces, but that may be a function of poorer 19th century bases and truck traffic in warehouse areas. Brick is undeniably more appealing. Two woonerfs are planned to be built this year in Mpls. One has concrete pavers, which don’t seem as durable as bricks. Does anyone know the square footage cost for bricks vs. pavers, both the raw material, installation costs and life-cycle maintenance?
As someone who commutes around Berlin by bike, I can tell you how horrible cobblestones and brick are to bike on. Traditional cobblestones are the worst. I see many cyclists riding on sidewalks (which tend to be small cobbles or flagstone style) to avoid the crazy bumpy ride. The brick off-street bike paths are better, but suffer from unevenness and are generally still a bit of a pain. Asphalt is a wonderful material for cycle paths, as long as it’s done on a good base, and repair patches are smoothed out. Sadly the repair people in Berlin do an inconsistent job of cycle path repair.
We have that problem in Minneapolis too. When I cross the river to St. Anthony on the Stone Arch Bridge, I’m never sure where they expect bikes continuing northeast to go: https://firstname.lastname@example.org,-93.2498611,3a,75y,43.67h,70.45t/data=!3m6!1e1!3m4!1sRL4F1weeqhEVpYIocNUSLw!2e0!7i13312!8i6656
When they tore up Lasalle downtown during the recent rebuild, I was surprised to see bricks under there (not sure how much of it, but I saw some).
Like most folks, I like the look of pavers. But in light of the expense and relative lack of funding for local streets, I think they should only be used sparingly, either as critically important “main street” projects (Nicollet Mall), or in situations in which the neighborhood wishes to pay for the improvement.
For example, when the streets in Country Club were replaced a few years ago, the neighborhood opted for attractive brick crosswalks — but also paid for them themselves.
I’d have to agree pavers look nice, but even question the “main street” usage without a commitment to maintenance. Northfield’s downtown brick crosswalks (financed through a downtown TIF district) looked lovely at first, but are crumbling quickly, have been patched ineptly, and crossing was more difficult for people with limited mobility even when new. The pavers punctuating the concrete sidewalks have fared badly, too.
I agree with SuperQ. After three months of biking on brick and cobblestone in Muenster, I long for good old concrete and asphalt. Even in the relatively mild climate here, the necessary maintenance on the cycle paths, with loose pavers and bricks, is not optimally accomplished. My bike is literally falling apart from the jarring. Also, the red brick of the cycle paths alongside the pedestrian sidewalks looks attractive, but many people don’t seem to realize they mark the bikeways and walk or stand in them regularly.
I love the look, but with the expense and the drawbacks, I’m not sure it’s worth it. Unless the drainage and environmental impacts are far superior.
Pavers are used extensively for road repairs in Chile. The initial road was concrete, they appeared to have cut out the potholed sections and then used pavers to replace the cut away damaged sections.
Easy to transport, no curing time required, no major equipment needed. The base under the pavers must not have been great, because many of the patched areas had dips and heaves.
To put a fine point on it, the paving blocks (more substantial that what we call “pavers” here) I remember seeing in Germany have a big advantage for street maintenance. If there was trouble with infrastructure below grade, workmen workmen would typically come during non-peak hours, lift the blocks, do the work, and put the blocks back in place before morning peak hours.
Old fashioned brick streets tend to become quite slippery when wet.
As to real cobblestones, in 1959 I rode a bike on Nantucket and found the quaint surfaces within the town difficult for walking and impossible for riding.
Currently there’s a pothole on Johnson up around 24th St in the NE that is a foot deep. It has brick at the bottom of it.
The new grooved concrete surfaces on 394 cause your car to wobble in the lane as your tire grooves catch the concrete grooves.
And when this new concrete surface is wet at night, it’s really reflective of light and it can be hard to see the lane line. Lots and lots of reflections, it’s dangerous, though I wonder if this reflection issues doesn’t go away as the surface degrades a bit.
Additionally, the wet concrete looks slippery (though it isn’t slippery in my experience) and that causes people to drive oddly.
If you think the rain grooves do a number on a car, try riding them on a motorcycle with two small contact patches. Tire manufacturers have tried to do away with grooves that follow the circumference because the tires were super susceptible to wandering with grooves.
Lateral grooves in concrete are noisier if I remember correctly, so linear is the preferred to keep things quieter while you’re trying to retain control of your vehicle.
It’s been a while, but I remember there being an alley in Summit-U neighborhood that was paved with wood bricks. I think it was between Summit and Portland, but I don’t remember the north south streets. Somewhere between Victoria and Lexington, though.
Having lived in areas where brick is in more prevelant use, I’ll say this: it has a nice aesthetic look to it, but it’s a maintenance nightmare. Furthermore, while it does tend to slow down vehicle speeds, it also makes travel more difficult for both bicycles and those with disabilities.
One option that was considered outside DC for the Alexandria, VA King St Metro station rebuild is “stamped concrete”. It combines the aesthetics of brick with the durability of concrete.
3rd St N in the North Loop is an opportunity to test out asphalt and brick side by side. Personally I prefer riding on the brick portions, which was paved at least 80 years ago, to the asphalt that the road has been patched with periodically. The lesson I take is that while new asphalt is undeniably smoother, brick holds up better over the long term. Of course, it’s possible that the brick of today doesn’t hold up as well as that of the past, and it’s likely that the techniques of laying and maintaining brick aren’t as widely understood as they used to be.
In my experience, brick tends to become very uneven as well, due to the underlying base conditions underneath the brick.
Columbus’ German Village (think St Anthony Main but with dozens of residential lined brick streets too) is a neighbhood chock full of brick streets and sidewalks with few exceptions. Not too bad to bike on, but for walking you have to pay attention since the trees push up the bricks around them. I don’t know that the bricks slow down motorists so much as the very narrow streets they’re on. With wider brick streets they still fly down at higher speeds.
Before we consider what to pave with we have to understand a few things. First, the brick surfaces that everyone loves so much are around a hundred years old. There are not many people around who know what they were like when they were new. The fact that they held up so well should give you an idea of their value. The picture above of Pillsbury Street in St Paul is a street that has to hold up to truck traffic, and it still looks pretty good. Trouble is no one seems to know how or want to make bricks like that anymore. They are semi-vitrified, meaning they are baked so hot the chemicals inside merge together like glass. But it’s better than glass because what makes brick red is the iron content, so those old bricks are almost like solid blocks of iron/glass. When they were baked they shrunk by an inch in each direction. Maybe there is something with quality of the clay or maybe it is just workmanship.
The bricks that are used nowdays are not made like that. They are porous and crumble easily. Anyone remember the street in front of the dome? It looks like they are sliced up rather than made individually by hand. In the Netherlands they commonly use brick shaped/coloured concrete pavers – fine for roads with slower traffic and less snow but they shred quickly here, even without traffic (witness the original light rail platforms).
Looks like I will have to write a post about bricks here sometime soon. Or maybe I just did.
Also to clarify, cobblestones are small rounded stones like one finds in creek beds. Some roads were paved with these but they are rare and very rough. Paving stones are what is used for what we for some reason refer to as cobblestones. We use big ones in the States. In Europe they still use the 4 inch cube version on a variety of patterns. It is still common to see granite curbs there, too, even on new streets – very nice, and very durable.
Ironically, Main Street at St Anthony Main uses new fake brick for the road surface, and the more durable old paving bricks for the sidewalk. Good thing traffic is tame there. Also I have seen streets in the Warehouse district that were paved with wood that must be really old, but it was not planks. It was more like railroad ties sliced like bread and laid like bricks. It may be covered now. Wood can be extremely durable if treated right. There are many wooden railroad bridges still in use that are more than a hundred years old.
Ok, fine, I’ll just do an entire post on brick paving, or maybe bricks in general.
Brick look to this crosswalk at Phalen and Payne intersection in St. Paul, but it appears to be fake brick based on its wear and the color. Nevertheless, I like the look and appreciate the different material appearance for the crosswalk. A bright red color or something else would have been even better.
I too remember wooden paving blocks on Como Avenue in St. Paul. I grew up about a block off of the Como/Hillside intersection in St. Anthony Park. The wooden blocks weren’t all that big, maybe 4″x6″ and treated with creosote like railroad ties. One problem was that some would pop out during heavy rain storms and just lie in the roadway. I suspect they could become dangerous projectiles if hit just right by a tire.