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High Speed Pedestrian Crossings
4

High Speed Pedestrian Crossings

High Speed Pedestrian Crossings

(OP)
I am looking for an alternative pedestrian crossing that would not require a pedestrian bridge.  This area is a 55mph county highway and the cost of building a bridge is not justified in this area.  I was just wondering what other alternatives other than a bridge were out there.

RE: High Speed Pedestrian Crossings

How about a tunnel?

RE: High Speed Pedestrian Crossings

(OP)
I am sorry I forgot to mention that this area is prone to flooding and a tunnel is not an option.

RE: High Speed Pedestrian Crossings

If you have cost restraints, there is probably only so much you can do.  If you answer these questions, it might help paint a clearer picture:

Is it acceptable to slow traffic down (i.e. stoplight, speed bumps or stop sign)?

How much sight distance is available?

What volume of peds and vehicles do you anticipate?

Have there been past vehicle/pedestrian accidents/incidents in this area?

How wide is the driving surface (two or four lane highway?) and is it paved?

RE: High Speed Pedestrian Crossings

Since you are dealing with high speed pedestrians, they should be able to outrun the cars, so where's the problem?

Seriouly though, if you can't go under or over, what other options do you have left other than through?   

Mike McCann
MMC Engineering

RE: High Speed Pedestrian Crossings

I would seriously consider the tunnel option.  

It seems to me that measures can be taken to de-water the tunnel sfter the flooding, possibly with an automatic sump pump system hooked to a solar array and a battery bank above the flood line (assuming there is an above).  The system could be remotely activated once the flooding had subsided.  A video link might be handy too to monitor the situation.

Mike McCann
MMC Engineering

RE: High Speed Pedestrian Crossings

You could always try catapults.

Sorry, it's been a long week.

RE: High Speed Pedestrian Crossings

My wife suggested a sky slide... as through a rain forest.

Mike McCann
MMC Engineering

RE: High Speed Pedestrian Crossings

Have you consiered an highway overpass with a pedestrian walkway installed at the existing grade?

If there is an existing crossing located within several hundred feet, you could put up a barrier and routr the pedestrians to the other highway crossing.  

RE: High Speed Pedestrian Crossings

I didn't think there were any high speed pedestrians in the country.

coloeng...yep, it's been a long week!

RE: High Speed Pedestrian Crossings

I was thinking when I read the title and the OP that if the pedestrians were that high speed, there wouldn't be any problem; they could beat the traffic.  Then I read MSsquared's post.  Yes, it has been a long week.

What about a solar powered on demand crossing light that the pedestrians could activate when they want to cross which would then stop traffic with a red light and let them cross.  When there is no one with a request to cross, the traffic has a green light.

rmw

RE: High Speed Pedestrian Crossings

All my jokes have been taken, so I might just suggest a serious answer.  Maybe a crossing with a refuge median, protected from traffic by barriers.  You enter the refuge, walk along the median a ways, then continue across the road.  Now that I think of it, is this for chickens?

RE: High Speed Pedestrian Crossings

I would suggest flashers, in addition to the refuge median suggested by hokie, and whatever other treatments (sidewalk!) might help improve visibility and hint to drivers to expect pedestrians.  Having been mugged in an underpass, I can see how one in a rural area might go entirely unused.  

RE: High Speed Pedestrian Crossings

francesca,

I don't think it would be unused, just unused for the intended purpose.  Probably used in the same way as the ones in cities, shelter/toilets for deadbeats.  And muggers.

RE: High Speed Pedestrian Crossings

Overhead cable cars like those in ski resort - nobody stops until it falls by wind.

RE: High Speed Pedestrian Crossings

"What about a solar powered on demand crossing light that the pedestrians could activate when they want to cross which would then stop traffic with a red light and let them cross.  When there is no one with a request to cross, the traffic has a green light."

Like a Puffin/Pelican crossing?

http://en.wikipedia.org/wiki/Puffin_crossing

55mph might be too high a speed for signals (certainly in the UK) on an otherwise unconstrained section of highway.

If you were to provide an uncontrolled crossing, with dropped kerbs and tactile paving and associated warning signing for motorists, would you be opening yourself to liability issues? If an accident occurred over here at such a crossing, we'd probably have a justification that such a facility was only an invitation or opportunity to cross, but it would ultimately be down to the pedestrian to judge their own safety. Would you have the same protection as the Engineer or would the crossing need to be essentially 'idiot proof'?

RE: High Speed Pedestrian Crossings

Hokie, Debaser, and Francesca are on the right track. Grade separated crossings, whether over or under, are expensive and unlikely to be used, unless the terrain on either side is favorable (i.e. the road is either elevated or depressed).

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

RE: High Speed Pedestrian Crossings

How far is the nearest existing crossing?  If not too far then a sign pointing that way would be all you need.

RE: High Speed Pedestrian Crossings

agoodall

I do not think there are any viable alternatives to above or below grade crossings. (in this case)

I cannot recall (other than signalized intersection) where a crossing would be permitted at this speed.

You could:
drop the speed, install cant. flashers, install warning signs.

Save up for the overhead bridge.

RE: High Speed Pedestrian Crossings

Now be serious.

In several suburban areas around Chicago, the speed limits on major business highways are arranged from 45 to 55 mph. There are traffic lights but rather far apart. Every once a while, there are person killed by taking short cut and competing with cars. Whenever I hear that, I feel bad for both. Also, adding extra traffic lights isn't an ideal option, without proper study on roadway geometries, surrounding environments, traffic volume and pattern, more problems could arise, such as running traffic lights. Lowering speed limit sounds good, but nobody would vote fot it when a 30 min drive becomes 45 or more.

Properly planned, designed, light duty pedestrain bridge seems a better solution. The design/construction cost can be offset by saving a few lifes, also, maight be paid by commercial advertisements.

RE: High Speed Pedestrian Crossings

agoodall,

We're really all shooting in the dark until you answer civilman72's questions! Posting alink to an aerial photo in Google maps or Live Search maps would help, too.

However, you could spend hundreds of thousands for a structure that may or may not get used (after working on a college campus for 3 1/2 years, I bet it wouldn't), or, for >= $30,000 (1) , put in a device shown to reduce pedestrian crashes by >50%. (2)

That's the chicken run, er, [ital]pedestrian refuge [/ital]described by hokie. (1)

References:
(1) http://www.walkinginfo.org/engineering/crossings-enhancements.cfm#crossing-islands
(2) http://ite.org/safety/issuebriefs/Desktop%20Reference%20Complete.pdf, page 100.

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

RE: High Speed Pedestrian Crossings

ACtrafficengr said;
"However, you could spend hundreds of thousands for a structure that may or may not get used (after working on a college campus for 3 1/2 years, I bet it wouldn't)"

I tend to work on the basis that, whilst pedestrians may go to environmentalist heaven long before car drivers, they are also the laziest of all road users (understandably). Give them the shortest practicable route at all times, otherwise they'll just take it anyway, but in doing so ruin your beautiful landscaping and grand plans with their desire lines.

hokie66 said;
"...I don't think it [a pedestrian underpass] would be unused, just unused for the intended purpose.  Probably used in the same way as the ones in cities, shelter/toilets for deadbeats.  And muggers."

And that's the problem of perception. We can demonstrate that a ped underpass is infinately safer than any at-grade crossing, but that idea of 'stranger danger' seems too strong to overcome. It's not unreasonable, and some of the terrible designs that we've forced peds to use in the past have basically come back to haunt us and created a situation where all similar facilities are viewed with suspicion. But any new ped tunnels now seem to be designed to be as short, open and light as possible without planting at the entrances and with entrance ramps long enough that blind spots are removed.

RE: High Speed Pedestrian Crossings

One prevented fatality pays for the pedestrian bridge or tunnel. I dispute your premise that it is not warranted.

RE: High Speed Pedestrian Crossings

Who said it was unwarranted? I do think it would not be cost effective. As cold as it may seem, it comes down to the math. Could same cost have more benefits used elsewhere? Without knowing the particulars, I'd tentatively hazard a yes in this case.

The same amount of money could be used for carefully targeted low cost safety improvements over the entire town, with a larger overall safety impact.

For example, I'm working on a high risk rural roads funding application that will treat a dozen sites for about half the cost of a ped bridge. In the 5 years I've worked at my county, we've had no pedestrian fatalities on county roads, and 10 run-off-road fatalities. Despite the fact that I have long been a bike/ped advocate, and participate with our MPO's bike/ped committee, I'm going after the single vehicle lane departure crashes. Why? Because they are >80% of our fatalities, compared to 0%.

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

RE: High Speed Pedestrian Crossings

Thanks, ACtrafficengr.  That is the kind of thinking needed in spending limited resources.

RE: High Speed Pedestrian Crossings

Civilperson said;
"One prevented fatality pays for the pedestrian bridge or tunnel. I dispute your premise that it is not warranted."

Unfortunately in road safety it never seems to be as easy as that.

Structures ARE expensive and are notorious for under-use/mis-use if they are not located exactly. As I alluded to in an earlier post, peds (unless they are simply admiring the scenery) want direct routes to and from their origins and destinations. Making them negotiate numerous ramps, stairs and landings doesn't appeal to many, and makes pedestrians feel like they are an afterthought in a motorised jungle.

RE: High Speed Pedestrian Crossings

ACtrafficengr said;
"The same amount of money could be used for carefully targeted low cost safety improvements over the entire town, with a larger overall safety impact."

I've just been involved in a number of accident studies for a Local Authority of a mainly rural nature, but with some large market towns and suburbs bordering on the edge of a large city.
We managed to identify 30 schemes that could be carried out within this coming years budget of approx. £500,000. These included civils works at single sites and on routes and education and training campaigns.
This compares with a single site that was identified in last years study (and is about to be built) which cost £200,000. Sadly balancing the budget does matter, even in matters of safety.

BTW, does the breakdown of single vehicle run-off-road accidents in your locality match with the figure available for the UK, and shown on this webpage?
http://www.ukroads.org/thepassiverevolution/stats.htm

RE: High Speed Pedestrian Crossings

It differs in the details, but that is pretty similar to our experience, with most fatalities resulting from collisions with trees, embankments or ditches, and rollover crashes.

We have a particular problem with single vehicle motorcycle crashes. Motorcyclists often favor unrestricted exhausts, in the hypothesis that "loud pipes save lives." They look at me funny when I reply, "But trees can't hear."

Overall US experience is similar. See http://safety.transportation.org/htmlguides/RORcrashes/types_of_probs.htm

PS: I like the UK's "Think!" campaign - especially the Julie PSA. Grab them by the guts, and hearts and minds will follow! Any agency that used it here would be sued for causing unnecessary mental anguish.
 

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

RE: High Speed Pedestrian Crossings

"We have a particular problem with single vehicle motorcycle crashes. Motorcyclists often favor unrestricted exhausts, in the hypothesis that "loud pipes save lives." They look at me funny when I reply, "But trees can't hear.""

Not to derail the thread too far, but I believe the Swedes have had some success in reducing motorcycle accidents as an unintended consequence of placing wire rope barrier down the centre of single carriageway roads to prevent head-on collisions involving cars/lorries.
I think the evidence pointed to m/cyclists slowing down due to the presence of this 'cheese wire' that was ready to amputate their limbs as soon as they hit it at any speed.
Sometimes I think we can make highways appear too forgiving, and perhaps overlook the fear factor as a psychological 'calming' measure.
 

RE: High Speed Pedestrian Crossings

As said before, it's either over, under or through. Burrowing sounds not logistically feasible. I like the idea of the pedestrian island. Perhaps you could have a crossing signal accompanying a 'train crossing' security gate?

My personal favorite though is, build a lightweight pedestrian bridge. Use it as a pilot program for a more permanent solution. If nobody ends up using it, just tear it down when it wears out and count your blessings you didn't invest in a significant structure. I'm sure you could design something creatively that fits the budget using a creative application of trusses and lighweight materials.

What's the span requirements?

RE: High Speed Pedestrian Crossings

Due to ADA requirements, there is no such thing as a cheap pedestrian grade crossing, unless the road is already in a cut. The ramps are just too long - 230'+ for a 17' high deck (pony or through truss, 15.5' to bottom of structure, 1.5' floor thickness).

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

RE: High Speed Pedestrian Crossings

There's much to be said for the catapult option. The below link indicates there is a spare one in england for sale:

<http://news.bbc.co.uk/2/hi/uk_news/england/nottinghamshire/7278993.stm>

Most pedestrian fatalities I read about in the newspaper that involve corssing a 55 mph rural road happen late at night- likely involve drunks. Maype a corssing overhad flahing light similar to railroad overpass warnings , but which require pedestrian input.

RE: High Speed Pedestrian Crossings

just reading this thread for the first time this morning and saw the following article...not endorsing the idea...just thought it was interesting

http://www.wtop.com/?sid=1654423&nid=732
 

RE: High Speed Pedestrian Crossings

@jeremyk55
just reading this thread for the first time this morning and saw the following article...not endorsing the idea...just thought it was interesting

http://www.wtop.com/?sid=1654423&nid=732


The article states that similar devices have been used in the UK.
Given the photo showing the striped crossing in the background I'm assuming they're talking about zebra crossings. In which case the zig-zags actually run down the channel lines and centreline of the road, not in the middle of the lane as in the picture.
http://en.wikipedia.org/wiki/Zebra_crossing


@kslee1000
On a 55mph road we'd be reluctant to use signals of any sort, pedestrian or vehicular, however we'd happily put in a dropped kerb (with or without tactile paviours) and let any adventurous peds take their chances...but then, Darwin was British.
 

RE: High Speed Pedestrian Crossings

Is this a problem without an optimum solution? So far we have;

Ped Overbridge/Underpass
Pros; Separates peds and vehicles completely,
Cons; Expensive, must be accurately sited on the desire line to be an attractive route.

At-Grade Signals
Pros; Offers some protection to those using the crossing, less expensive than bridge/tunnel,
Cons; 55mph is a high speed for stand alone signals (see attacment for UK view)

Unsignalised At-Grade Xing (Drop kerbs and tactiles only)
Pros; Cheap
Cons; No protection for peds other than 'common sense' when to use crossing
 

RE: High Speed Pedestrian Crossings

(OP)
I appreciate all the comments, it is good to have a little laugh now and then.  I brought some of the comments on myself with the title of the thread and I know that.  The project has not been completed yet, and when I posted the thread we were just in a feasibility phase.  We are still in that phase and it was good to get some different opinions.  Thanks for your help

RE: High Speed Pedestrian Crossings

If you can destroy and rebuild a section of the highway, you could always make a trench so the highway is on a hump and the pedestrianway is then at normal ground level.

RE: High Speed Pedestrian Crossings

I would think the lane-narrowing concept from this report could be applied to a mid-block pedestrian crossing:

www.tfhrc.gov/safety/pubs/08063/index.htm

A statistically significant 5 mph reduction in the 85% speed is nothing to sneeze at.

 

     "...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

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