The 2015 “Bicycles On The Freeways” Incidents

March 24, 2017 at 4:28 pm | Posted in Bicycling | Comments Off on The 2015 “Bicycles On The Freeways” Incidents

On June 16, 2015 in St. Paul a 14-year-old girl was bicycling from her friend’s house home and followed directions from her phone- which led her down I-94 at rush hour. Mn/DOT traffic cameras immortalized the incident. In the first we see her riding down the shoulder; traffic management turns on the flashing yellow lane control signals for the outside lane to warn motorists.

In the second video, state patrol has arrived and is talking to her, then escorts her off the nearest exit ramp for her to continue her trip on city streets. At least she was wearing her riding helmet.

Riding a bicycle on a freeway in Minnesota is of course illegal,

169.305 Controlled-Access Rules and Penalties
 Subdivision 1
(c) The commissioner of transportation may by order, and any public authority may by ordinance, with respect to any controlled-access highway under their jurisdictions prohibit or regulate the use of any such highway by pedestrians, bicycles, or other nonmotorized traffic, or by motorized bicycles, or by any class or kind of traffic which is found to be incompatible with the normal and safe flow of traffic.

Although the situation is ambigous in some places like the Cannon Falls bypass, in the Twin Cities all the interstates are clearly posted. The state patrol let her off with a warning rather than a citation. This of course leads to interesting questions on our blinding trust in technology; “phone guides motorist into the lake” incidents happen now and then. And there was that Tesla incident where a man was watching Harry Potter movies while the car drove him into a semi.

In the Twin Cities, phones have “outsmarted” local agencies; guiding motorists on a shortcut through a ritzy Edina neighborhood that’s a lot shorter than the official detour on freeways, much to the distress of residents. As a last resort the city finally closed down the street.

A 14-year-old doing something clueless and dangerous isn’t shocking, but the same summer there were three more incidents, involving adults. The very next day a man was bicycling on the freeway in Woodbury, but exited before state troopers could intercept him. A third incident took place on August 19 in New Brighton. In this case the man was actually in the traffic lanes; the teenager at least had enough sense to use the shoulder.
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Then on September 9 the fourth incident didn’t have a happy ending when a man was killed bicycling on I-94 near W. Broadway in Minneapolis. There’s endless debate about where bicycles do and do not belong, but I don’t think anyone disputes an urban freeway is not the place.

 

Bicycle Helmet Use in Minneapolis and Suburbs, 2015-2016

October 19, 2016 at 1:54 am | Posted in Bicycling | Leave a comment
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Here are the results of a research project documenting bicycle helmet use in the Twin Cities in 2015-2016. This isn’t met to be comprehensive, but to give some idea of helmet usage in different areas as well as a brief history.

A History of Riding Helmets

Advocacy for wearing bicycle helmets is almost as old as bicycles themselves. In the 1880s bicycle clubs began to advocate for the use of helmets. Eventually racers began to use helmets, first leather type pith helmets, then leather ring type “hairnet” helmets, but it was unknown in casual bicycling.

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Leather Hairnet Helmet

The first thing resembling a modern bicycle helmet was put out by Bell Sports in 1975, the Bell Biker, and was a modification of motorsports helmets, made of polystyrene foam with a hard lexan shell. These continued to evolve to the early 1990s (most noticably replacing the act of threading the chinstrap through rings with a quicker to use buckle).

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1980s-early 1990s hard shell helmets

Hardshell helmets have stuck around in a way, they’re now “skate style” helmets. The skate standard calls for limited multiple impact proection; some of these are skateboard only, some are dual-certified, and despite looking like skate helmets some are bicycle only. Like the earlier hardshell helmets they’re hot and heavy for bicycle use but they do provide an alternative design.

They’ve also morphed into “Urban” helmets, like Bern

Another neat idea, and R2D2 helmet

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R2D2 Helmet

From the UK are Yakkay brand helmets, which are hard shell helmets with a decorative cloth cap on them. It seems they’d be unbelievably hot, but I guess it’s worth it to make it not look like you’re wearing a riding helmet.

Late 1980s: Soft Shell Helmets

In the late 1980s came improvements that negated the need for a hard, heavy outer shell. One of the first, the Bell Ovation, had a soft lightweight shell, but more commonly they had no shell at all. Most of them had a Lycra cover to make it look like you weren’t wearing a picnic cooler and to provide a bit of protection from handling damage. Unfortunately in practice these tended to shatter into pieces and scatter at the first impact leaving the user vulnerable to further impacts. Manufacturers experimented with a wire mesh, but ultimately returned to soft shells. The color of the foam eventually generally changed from white to black to reduce the “picnic cooler” or “mushroom-head” aesthetic.

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Ovation and the shell-less helmets that followed

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Early Soft shell helmets, shell taped to liner

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Old Shell-less helmets with black foam, Rottnest Island Australia

Late 1990s: In-Mold Shell.

In the early 1990s came another innovation, injection molding the foam into the shell, rather than manufacturing them separately and then taping them together. Initially it meant the front strap or strap anchors were exposed, but later on they figured out how to make them recessed. Of course the trend towards  models with more an more vents came out.

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In-Mold Helmets.

In the mean time, an occipatal lobe retainer became standard, this is the strap that runs across the back of the head, and later ring fit systems, where you tighten a fastener on the retainer, enable one size fits most helmets.

Later Refinements:

With the advent of ring stabilizers, the dilema “where do you put your pony tail” comes up. (Most helmets don’t curve up like the one above). Specialized has ones that do, they call it the “Hairport”.

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Specialized “Hairport”

Another refinement is Bell’s “True-Fit technology, which eliminates the long, error prone, and often skipped process of trying to adjust the straps to get a helmet to sit right on a head. Specialized and Uvex now have similar systems.

Recently MIPS helmets have come out. One of the criticisms of helmets is they can increase the torque applied to the head in the event of a crash, MIPS is basically a layer of slick plastic that allows some slippage between the head and the helmet.

Selecting a Riding Helmet

So with all these advances in technology, is your new $200 helmet safer than your old on from the 1990s? Probably not.  There’s been various safety standards at different times and place,s but there’s been no real-world differences noted since the adoption of the ANSI standard in the late 1980s. No manufacturer is going to come out with a design that is “50% safer than brand “X”, for a number of reasons.

  1. The things that would make a helmet safer, namely thicker foam and fewer vents, would make it less marketable
  2. This would expose them to potential liability
  3. The safety tests performed are go/no go tests, there’s no standardized tests to say a helmet exceeds them by X percent, and it would be even harder to say that they were X percent safer in the real world.

If you look online for recommendations, there’s a lot of push by the helmet manufacturers to buy the most expensive helmet possible (and note they never say “safer”, they say “better ventilated; more stylistic, whatever). Meanwhile the Bicycle Helmet Safety Institute (actually one guy who’s been advocating for helmets since the early 1990s) has the following suggestions:

You want a smoothly rounded outer shell, with no sharp ribs or snag points. Excessive vents mean less foam contacting your head, and that could concentrate force on one point… Skinny straps are less comfortable. Dark helmets are hard for motorists to see. Rigid visors can snag or shatter in a fall. Helmet standards do not address these problems–it’s up to you!

Unfortunately this results in the type of foam picnic cooler bicycle helmet that would, as the Onion notes, protect against bicycle helmet inspired beatings. Some of these recommendations would seem to make sense, but the safer helmet is one that would actually be worn, and there’s been to my knowledge no objective studies of these contentions.

And despite the “one size fits all claims”, there is a wild difference in how well helmets fit. The usual advice is that Bell fits round heads and Giro fits oval heads, but there’s more nuance than that. BHSI found the Tru-Fit worked less well than traditional systems, but others have found the opposite.

The Helmet Controversy

But should a riding helmet by mandatory, or even worn in the first place? Everyone points to the original study saying they reduce head injuries by 85%, or tell stories about how a helmet “saved their life” without any actual evidence. So it’s time to look at some of the controversy:

The original study itself may not be definative. Helmet promoters a repeat a 1990 Seattle study that helmets reduce the risk of head injury by 85% ad-nauseum, but followup studies are not so conclusive. In fact the CDC and NHTSA have withdrawn their support of the study The main criticism, besides being a single source that hasn’t been repeated, is that it doesn’t take into account some of the other variables described below. The authors themselves have revised their number to 69%, which still isn’t borne by real-world experience.

There are direct technical drawbacks. A helmeted head is much bigger than a un-helmeted one, which may lead to head contact that might not occur otherwise, and the torque that can be created is bigger. The trend towards smoother rounded helmets and the use of slick plastic lining in some of the newer ones, “MIPS” helps mitigate this, but it is still a problems.

It’s a distraction from the real issue, that the best way to be safe is not to crash. Again, the best crash is one that never happens, not one that you attempt to mitigate with a helmet. People think that if they convince people to put on a helmet they’ve done good, without addressing the much, much,  more important issues of safe riding skills and infrastructure design. Helmets are next to useless in bicycle vs car crashes, and motorists drive more aggressively when they see a bicyclist wearing a helmet. One guy from the UK measured this and found motorists get 8.5 cm closer to a bicycle when the rider is wearing a helmet

Risk Compensation may cancel out any direct benefits. Of course seat belts have this effect too, but in that case the direct safety benefit overwhelms any risk compensation, and overall motor vehicle safety trends bear that out. That’s not so clear with riding helmets, and safety trends are inconclusive. One study went so far as to objectively measure risk taking while wearing helmets. Anecdotally, the time as a motorist I had to do a panic stop to avoid hitting a teenage boy that had run a stop sign onto a major street, he was wearing a helmet.

The “dork factor” and discomfort leads to a decline in bicycling, which increase societal health costs and makes things more dangerous for all bicyclist. When Australia introduced mandatory helmet laws,  in the early 1990s, cycling trips declined by 30-40 per cent overall, and up to 80 per cent in some demographic groups, such as teenage girls. Simply put, bicycle helmets tend to be hot and uncomfortable, and produce the dreaded “helmet hair” as well as looking bad, and for some people it’s not worth it to ride if they have to wear one. Once of the best way to make bicycling safer is to make more bicyclists, so motorists get used to seeing them around.

From my pictures above it’s obvious helmets have come a long way in comfort, but some of the more expensive lighter and better ventilated ones cost as much as a department store bicycle so it’s unrealistic to expect everyone to have one that expensive. So the ones you find at Wal-Mart or at helmet giveways aren’t so nice. Here’s a helmet giveway from New York. The fancy graphics tend to disguise the fact that these would have been considered average ventilation… for 15 years ago.

I’ll also point out theirs a snob factor in certain elements of bicycling in the US too. When I still had a cheap department store bicycle one a guy on probably $1000 mountain bike stopped me and told me how lousy it was and I needed to upgrade. And when I was looking to buy a decent bicycle, at a store on Snelling in St. Paul,  as a guy with long hair maybe I didn’t look like the type that had $700 in his pocket to spend on a road bicycle. So I walked out of a St. Paul store after all three clerks spent 45 minutes helping a middle class looking family buy a helmet for their kid while ignoring me. To put it visually, suppose we make a comparison of stereotypical bicycling in the Netherlands vs the US…

The “Build it for Isabella” program encourages bicycle infrastructure design to be accessible to all. But the perception of bicycling needs to be more accessible too. For now Isabella wears her riding helmet, but will she keep bicycling as she gets older and has other options to get around?

build-it-postcard

This isn’t to fault people that make the decision to wear a helmet and bicycle clothing. After all we make decisions all the time that increase our personal safety and comfort to the detriment of the rest of society, say buying an SUV because it’s comfortable and safe rather than a small electric car. I’m just pointing out that this is an issue. Bicycling culture needs to be as accessible as bicycling infrastructure.

Helmet use is generally incompatible with bike sharing. Look at this chart.

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Minneapolis may be towards the bottom because the climate is considerably harsher than the other cities and bicycling less established, but the bottom two cities have mandatory helmet laws and the rest do not. Rental or “disposable” helmet vending machines have been invented in response, but beyond discouraging usage this adds to the expense and complexity of running the programs.

A reasonable conclusion for all this is that as an individual you might be safer in a helmet provided it does not induce you to ride less safely in other respects, but the benefits are not as great as portrayed, and since all of life involves risk of some sort, and the risk of bicycling isn’t that great, riding helmet use should be an individual choice rather than forced to by laws or societal pressure. (And in case you’re wondering, despite my esoteric interest I rarely do myself; after looking at the risks and benefits I usually only do when on crushed limestone trails).

Finally the Statistics: Bicycle Helmet Use in Minnesota

So, with that said, here’s the data on riding helmet use in Minnesota. I’m not going to even attempt to say “X” percent use helmets, because there’s so many differences depending on age and location, so I’ll merely present it.

First adult helmet use on the Minneapolis off-road paths (that I term the “parkways”): Minnehaha, Calhoun, Harriet, Isles, and the Greenway, primarly during prime bicycling hours and weather.

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Bicycle Helmet Use: Minneapolis Parkways, All Adults

One thing I noticed is that helmet use drops like a rock at dusk when the traffic thins out. My theory is the people that have made it a destination trip have gone and it’s more locals.

Second, the Minneapolis Parkways broken down by age and gender.

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Bicycle Helmet Use, Minneapolis Parkways, Breakdown by Age and Gender

I did this several years ago (and appear to have lost the data), but I recall there was a much more significant difference between men and women; at the time men were around 50% while women were about the same at 60%.

Now the Minneapolis Parkways in comparison to other areas. “City Streets” are areas not on or immediately adjacent to the parkways in Minneapolis and St Paul (but note I have no reason to go to the poorer areas of town), “Inner Streets” are suburbs with grids, mostly East Bloomington. “Outer Streets” are suburbs with twisty streets and usually bicycle paths along the main roads, mainly Eden Prairie and Shakopee.

One observation is the helmet use varies widely in different neighborhoods of Minneapolis, being highest in say the southwest, and lowest in the poorer areas (which I normally stay out of so don’t have meaningful comparative data).

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Bicycle Helmet Use in Minnesota- All Areas

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Bicycle Helmet Use broken down by age an gender

Helmets for Inline Skating: Also on the charts are use by inline skaters.After some talk of developing an inline skating standard, they decided just to use the existing bicycle helmet standard. Inline skaters may be better served by those helmets that provide more rear protection like skate-style helmets and a few mountain bike helmets, but these tend to be less ventilated then would be ideal for the slow speeds and intense, continuous work of skating.

Nice Ride: As I noted above, helmet use is difficult with bicycle sharing, and the statistic seem to confirm that. I think these may be too high even as my first count included a large group of men riding together with helmets, something I didn’t see for the entire rest of the summer.

Bicycle Riding by Gender

Maybe if you’re not interested in helmet use, you might be in the total of men vs women bicycling. I counted 839 men and only 540 women. You could probably speculate endlessly on the reasons for the difference, but I’ll leave that to other. I’m just a transportation geek interested in some of the more oddball elements sharing my findings.

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Images and text Copyright 2016 by Monte Castleman, All Rights Reserved, except for hotlinked images or those licensed under Creative Commons as noted.

A New Life for the Old Cedar Bridge

October 1, 2016 at 11:52 am | Posted in Abandoned Highways, Bicycling, Bloomington and Suburbia, Bridges, Streets, and Highways | Leave a comment

 

[Originally Published May 2016]

The Old Cedar Bridge is now open, but it’s been a long road to get to this point. THis article takes a look at the restoration and reopening of the Old Cedar Avenue Bridge. (I’ve chosen to consistently refer to it as the “Old Cedar Bridge,” it was originally known as the “Long Meadow Bridge” to distinguish it from the river span).

Old Cedar Ave Bridge Around 2002

The Old Cedar Bridge, around 2002

Inception of the Bridge

Although the bridge was only part of the state trunk highway system for a generation, history is intertwined with it. In the old days, if you wanted to travel south from Minneapolis, you first had to travel to St. Paul, then cross the High Bridge and head out on the old Dodd Road. Then you could take a road through Farmington to Northfield to Faribault to Albert Lea that eventually became part of the Jefferson Highway and later on was designated Trunk Highway #1. Directly south of Minneapolis lay nothing but ferries (that had existed since the 1850s) and routes suitable for local travel.

It wasn’t long until demand for improvements were made. Around 1890 two new bridges were funded by the state legislature as part of a generation-long period of increasing state involvement in roads before the formal establishment of the state highway system. One bridge replaced the ferry at Bloomington Ferry Road, and one extended Cedar Avenue across the river. Although the river spans were long-lasting steel swing bridges, the original bridge over Long Meadow Lake was a rudimentary wooden trestle. These choices were not without controversy. Minneapolis business interests favored a crossing at Lyndale Avenue, the most direct route to the south. It was thought that extending Cedar Avenue would be of more benefit to St. Paul, which already had well established roads to the South, and that Bloomington Ferry was way out of the way.

During the 1910s, it became obvious that the automobile was the wave of the future for personal travel, and trucks for commerce was imminent, and demand for more and better roads continued. Although the marked auto trails system provided consistent guidance, actual maintenance fell to a labyrinthine assortment of agencies, and the maintenance was anything but consistent. Momentum grew for the state to assume maintenance of roads of statewide significance, and the Minnesota Highway Commission was formed in 1911. The state provided aid for major roads and standardized plans for bridges. In turn structures needed to meet state standards, which the Old Cedar Bridge obviously did not. In 1912 the Dunn Amendment was passed, providing for changes to the Minnesota constitution to allow a trunk highway system. In 1917 the Minnesota Department of Highways was formed with Charles M. Babcock as the first commissioner, and in 1920 the state constitution was amended. Finally in 1921 legislation was passed and the trunk highway system debuted.

With regards to the Bloomington area, two more bridges were planned as part of this ramp-up of state involvement in major highways. A crossing at Lyndale Avenue and the replacement of the wooden trestle on Cedar Avenue with today’s steel structure. World War I delayed building, but after the war plans resumed. The original plan still seemed to be that Cedar Avenue would be the main route southward from Minneapolis; my 1920 map shows a proposed road between the bridge and the existing north-south road to the High Bridge and Farmington and it was paved from Minneapolis to the new bridge.

Proposed Cutoff from Minneapolis to the main north-south highway at Farmington

But Babcock favored Lyndale Avenue, replacing an old ferry at the foot of Hopkins Road. Then focus shifted to improving the even more direct route, first with a cutoff from the bridge to Farmington (what is now County 50), then a direct route south to Faribault which became US 65 and then I-35. Here’s the trunk highway system about 1925, after all the routes that were planned were actually laid out. Route 1 was the main route north and south of the metro, with cutoffs from Minneapolis (Routes 50 and 63) which took a few years to implement leading to it.

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Trunk Highway System about 1925. The Farmington Cutoff between Lyndale Avenue and the main trunk highway at Farmington had been built as Route 50, and note that the Bloomington Ferry Bridge was the main route to the southwest leaving Cedar Avenue left to local traffic.

 

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Charles Merritt Babcock

As a side note, despite Babcock’s role in advocating and creating the trunk highway and his national profile (he was president of the American Association of Highway Officials) his career was cut short. As evidenced that almost from the beginning politicians have fancied themselves as highway engineers, Babcock was fired by Governor Floyd B. Olson for refusing to accept an absolutely massive expansion of the trunk highway system. Some of which, like MN 100 Beltline or MN 55 west of downtown, were worthy candidates. But many of which were both then and today extremely dubious inclusions for the trunk highway network. This included a portion of MN 65 through the north woods that sees and average annual daily total traffic of 30, and spurs to serve the unincorporated hamlet of Island View and a private resort on Lake of the Woods. Today, I doubt many people know or care who Babcock Trail was named after and his legacy to the state.

The Bridge Opens

In late 1920 the Old Cedar Bridge opened, at the cost of $114,940. It was Hennepin County Bridge #55, but also assigned a state bridge number, #3145. It was a maintenance nightmare from the beginning. and there were calls for its replacement as soon as 1956. Ten foot lanes may have been adequate in the early days when the only traffic was a car now and then, and semi trucks weren’t as prevalent. Early trunk highways had 9 foot lanes as standard. But even by the 1950s it was considered awkwardly narrow, and both the railing and structural elements being hit by vehicles was a regular occurrence.

Although neglected, this neglect also led to its preservation, as the old Lyndale Bridge was demolished when I-35W opened. The bridge wasn’t even part of the trunk highway system until MN 36 was extended in the mid 1950s. In 1962 the concrete deck was replaced with a wooden one. As late as 1970 there were only around 11,700 vehicles a day using it, but around that time east Bloomington approached becoming fully built out.

As the American Dream crossed the river, regional commuter traffic increase dramatically, and with the Met Stadium and the “New Zoo” there was renewed interest in improvements. Finally in 1980, what long term residents like myself still call the “New Cedar Bridge” opened. The old 1891 swing span across the river was demolished, and the Old Cedar Bridge was transferred to the City of Bloomington, against their wishes, to provide access to the river bottoms.

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New Cedar Bridge Invitation

Unlike more recent turnbacks where the road was fully reconstructed, Bloomington got the well-used bridge “as-is.” They did not have the funding or wherewithal to maintain it, so it continued to deteriorate. In 1993 it was closed to motorized vehicles. With no road access, this marked the end of the river bottom farms, and they became part of the wildlife refuge through sale and tax forfeiture. Even without paved trails in the river bottoms, it was still frequently used by bicyclists and pedestrians. Then finally the Old Cedar Bridge was closed to all traffic in 2002, severing a key link for bicycles across the river.

The Bickering Begins

From then on, there was a desire to replace the connection, but the bickering went on for over a decade. Bloomington saw themselves as in the business of transportation, not historic preservation, and sought the cheapest way possible to provide that service. Bloomington has insisted it couldn’t pay for repairs; that it shouldn’t have to do it alone for what is a regional amenity; that it shouldn’t have to deal with something that will require extensive maintenance in the future.

Meanwhile, as early as 1994 there were calls for the preservation. Through-truss bridges aren’t by themselves historic (two are being demolished in the Lanesboro area this year). The Old Cedar Bridge is one of only three truss bridges in Minnesota that predate the trunk highway system, and five sections on a Parker Through-Truss design is uncommon.

Nor was the bridge designed to be aesthetic. Trusses were just the way longer bridges were built in the era of cheap, abundant steel and immature concrete technology; thinking that they look nice came later after most of them were demolished. The New Cedar Bridge (and its contemporary, the Bong Bridge) were the last ones in the area built with massive structural elements above the bridge deck that were driven by engineering needs. The steel arches on the Hastings and Lowry Avenue bridges, and the concrete towers and steel cables on the St. Croix Crossing and Hennepin Avenue Bridge are there because people liked they way they look, and they cost substantially more than a generic concrete bridge would have.

Silverdale Bridge on the Gateway Trail

Another Parker Through-Truss bridge, this one a single section from 1873, now located on the Gateway Trail. The single lane wasn’t a problem with 30 vehicles a day at its longtime location on MN 65 in the north woods at Silverdale.

The original proposal was an earthen causeway to be built in conjunction with a new gas pipeline. Fish and Wildlife said no, so from then on Bloomington pursued funding to demolish the structure and build a new one, which would have been half the cost and easier to maintain. There was a 2008 study, and a bill that would have provided money for demolition and replacement. One idea was to set the old trusses on the new bridge as decoration. Then the bridge got officially designated as historic and in 2013 the federal government made it clear that they would not allow demolition. With only one option now, Bloomington commissioned a 2014 study for rehabilitation, and thanks to longtime local Representative Ann Lenczewski, $14.3 Million in state and federal funds was allocated.

Obviously, the bridge is badly missed, but I hope I have provided an explanation why it took so long to sort things out. Here’s a map of the bridge in context, showing how it and the soon to be built I-35W trail crossing will connect existing and proposed trails in Bloomington and Minneapolis to the rest of the Twin Cities to south of the river.

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Bicycle Minnesota River crossings (Green- Existing, Yellow- to be built), and select existing (red) and proposed (black) trails.

The Nuts and Bolts of Restoration

So now that the decision was made to restore it, more decisions had to be made. when restoring an old structure. There’s a lot of philosophical issues and sometimes conflicting goals. You want something functional that will be cost effective to maintain.

The Foundations in the river turned out to in pretty good shape, and will for the most part be left as-is

The Piers and Abutments are not in good shape. Normally with historic restoration you attempt to save as much as practical. However in this case the outer layers of all the piers were peeling off. Saving a historic core in the middle while replacing the concrete on the outside would be technically challenging, and possibly even dangerous to workers while leaving no historic concrete visible. So the decision was made to completely demolish and replicate them, down to using wood boards as forms as was done in the old days to leave a distinctive, rough edge.

The Deck was in even worse shape. This is what led to the closure, and it continued to rot in place. Some photos show how you can see daylight through some of the decking members.  Initial plans were to attempt to repair it, but it soon became evident it was a lost cause. The 2008 proposal was to use laminated wood planks that would be placed side to side, negating the need for steel stringers underneath the deck.

The current plan is to use a special, lightweight modern concrete with a completely redesigned joist and stringer system, . This replicates the original concrete deck, although the asphalt wearing surface will not be applied to save weight and as there is no engineering need. The new lightweight deck system will lessen the wear on the remaining historic, visible parts of the bridge, while still allowing bicycles and pedestrians and the occasional emergency or maintenance vehicle.

The Trusses by contrast are in pretty good shape. One of the chords on the bottom (where it was hit with salt spray) would be only 1% above the required safety factor, so the decision was made to replace it as part of the project rather than the probability of having to come back in the few years and do it anyway, requiring another closure and construction mobilization. Some of the diagonal bracing has been bent by being hit with vehicles; this is not a safety issue and they never bothered to fix them before, but they are being straightened now, as the report notes: “the site of bridge members in this state of distress could cause the public unnecessary concern”

The bridge never had lighting, and they are not adding it now. It was considered, but it was noted that “the refuge is closed after dark.” Obviously the east-west trails will be closed, but it’s an interesting point whether it will be legal to travel north-south across the river. The old bridge had an “Area Closed After Dark” sign on it, but it appears you can use the bridges without leaving city-owned property and the New Cedar Bridge has a light on it for the trail as well as spill from the roadway lights. At any rate there are no street lights on road south of the bridge and as poorly as Bloomington lights their streets, not a good idea to be riding around without a good bicycle light after dark anyway.

As far as color is concerned, we all know the bridge as a rusty brown, which is actually a good match for the painted brown new bridge as well as blending into the natural surroundings. However it will be returned to it’s original dark grey color.

See this beautiful railing from the Holmes Street Bridge in Shakopee?

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Holmes Street Bridge Railing

The Old Cedar Avenue Bridge railing is nothing at all like this. In fact it’s nothing but the type of gas pipe you buy at Home Depot. The original bridge was way out in the sticks, so unlike those closer to the city, little thought was given to ornamentation, and as I mentioned in the last part they had no idea they were creating beauty instead of just transportation. This leads to some philosophical and practical issues. Normally you want to save as much of the original structure as possible, but a gas pipe in 1920 looks a lot like a gas pipe in 2016 and virtually all of it would have been replaced already due to collision damage. Note how nondescript and bent out of shape the railing is. Not surprisingly, no one bothered to keep good records as to when they had to go out and replace which small section of it.

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Old Cedar Ave Bridge in 2002

Moreover, the original configuration doesn’t meet modern standards for bicycle and pedestrian facilities–it’s not high enough and there’s too much space in-between the rails. So the what’s being done is

  1. The existing railings will be scrapped entirely
  2. New railing is being assembled out of gas pipe and the top rail will be somewhat higher than the original
  3. Steel cable will be used in-between the gas pipe to reduce the spacing to meet standards. Steel cable is allowed for railings as long as it it not the topmost rail (on the Holmes Street bridge photo you can see a single cable was added to allow it to meet specs.

Even the nuts and bolts are thought of. The original bridge used rivets exclusively. Nowadays riveting is becoming a lost art, and is prohibited for certain structural parts. The plan is to use rivets on visible pieces where it’s allowed and on pieces fabricated in the shop. Button-Head bolts, which resemble a rivet from one side at least, will be used in other visible areas, and the contractor will be allowed to use standard hex-head bolts underneath the bridge where no one but the frogs will see it. Generally, the bolts will be mounted button head inward, due to both practical concerns with getting a wrench in tight places, and aesthetic as the inside side of the bolts will be viewed up close. This unavoidably alters the aesthetic slightly from the outside. Consideration was given to putting plastic caps on the outside, but they would still stick out more, and that would introduce an inappropriate material.

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Button Head Bolt

The Project Begins

The project initially got off to a rocky start. To begin with, CenturyLink had move a fiber optic cable that was in the way. Their boring machine broke, and it broke directly underneath a significant oak tree, which they were not allowed to cut down to retrieve it, so they had to bring in a new machine and start boring again from the beginning. The second task was the building of a temporary bridge in order to provide access.

Next demolition of the old bridge deck was done with small excavators removing the wood, an then the rotten steel was removed.  Next massive cranes were brought in and shoring towers were built and an entire section of the bridge was lifted off the piers which is easier to do with no decking, only lightweight temporary bracing to keep it in shape. This is very impressive visually with the huge cranes dwarfing the bridge. While suspended the piers were being demolished and rebuilt and the gusset plates evaluated and replaced if needed. The bridge has now piers, and construction on the new deck is underway.

cedar-bridge-13

Old Cedar Bridge Shoring Towers

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The northernmost span has been set back down and is ready for the deck to be built, April.

Trailhead Improvements

Going together with the long term plan to reopen the bridge and open the valley up to a wider demographic by filling in a gap in our paved trail network are plans to make the trial-head more functional and attractive, and even enable school groups to visit. Some invasive underbrush and non-significant trees are being cut down around the parking area. Significant canopy trees are being left. This will provide a more open, attractive, park-like atmosphere around the immediate parking area, and increase the perception of safety. (“Perception” being the term from the study, not mine). A mowed, maintained area for picnicking will be located between the bridge and the parking lot. A modern restroom and shelter building is being built just out of the floodplain on the east side of the street. A new boardwalk with rails has replaced the a rotting structure.

Earlier plans were to add nothing but a striped biked lane going uphill (northbound Old Cedar) and sharrows going downhill. The revised plan includes a fully protected eight to ten foot off road trail. This will be a city-owned extension of the Nokomis-Minnesota River Regional trail that now runs between the Minneapolis network and 86th Street, and also connects to the Nine Mile Creek Regional Trail. This is a challenging engineering feat, with wetlands on the east side and a steep slope on the west. Since you open up all kinds of issues by cutting into a slope, the trail will cross to the east side near the curve. Originally they were looking at a boardwalk, but now it’s apparent something more like a bridge will be needed.

As a side note, I arrived an hour into the meeting about the new trail, and was only the second person to sign in. Does Bloomington not care about bicycling because the off-road infrastructure is so poor (the Nokomis trail is the first off-road paved trail anywhere in the eastern half of the city), or is it so poor because Bloomington doesn’t care? Or do people just figure it was going to be built anyway, and are not interested into finding out more in advance or providing input? I do know that public meetings aren’t the best gauge of public opinion, they tend to skew towards older people with more time on their hands, and people really involved in the community (the previous name I recognized as a regular contributor to the East Bloomington Residents Facebook Group). At least I got plenty of time chatting with the city engineer about this and other projects.

Finally, back to the bridge: the informal name is now official; the Long Meadow Bridge is now the Old Cedar Bridge.

Minnesota Statute 161.14 Subd 77: Minnesota state bridge number 3145, the Camelback bridge over the Minnesota River overflowage (referred to as Long Meadow Lake) constructed in 1920, is designated and named the “Old Cedar Avenue Bridge.” This designation and name also applies to any renovation or reconstruction of the bridge and must be used in any publicly financed signage that refers to the bridge.

Yes, it was expensive, but sometimes nice things cost money and this was money well spent.

Old Cedar Ave Bridge

The New Old Cedar Ave Bridge

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