We received some informative material from gentle reader Dan S. this morning, something which we believe will be of interest to those of you who are closely following the Powder Mountain Development situation. We incorporate below a letter sent by Professor Schroeder to the Weber County Commission, on behalf of the Ogden Sierra Club:
To: Weber County Commission
From: Dan Schroeder, Conservation Chair, Ogden Sierra Club
Re: Powder Mountain road
Date: 11 July 2008
Dear Commissioners:
At Tuesday’s public hearing regarding the proposed Powder Mountain rezone, a couple of speakers made comparisons between the Powder Mountain access road and the roads leading to some of Utah’s other ski areas, specifically the Cottonwood Canyons and Brian Head. So you won’t have to rely on qualitative impressions, I’ve plotted the elevation of each of these four roads vs. horizontal distance:
As you can see, none of the other three roads is as steep as the Powder Mountain road, whether one compares grades over long stretches or shorter segments. For example, the steepest 1000-foot-vertical portion of the Powder Mountain road has an average grade of approximately 14.0%, while the steepest 1000-foot-vertical portions of the other roads are approximately 7.0% for Big Cottonwood Canyon, 9.4% for Little Cottonwood Canyon, and 10.6% for Brian Head. The comparison for 2000-foot segments or 500-foot segments is similar: Powder Mountain always “wins” by a substantial margin. Therefore it is invalid for proponents to imply that the Powder Mountain road would present no more access and safety problems than these others.I obtained this data from rasterized copies of the standard USGS 7.5-minute topographic maps, sampled at each point where the road in question crossed a 40-foot contour line. This method over-estimates all the slopes very slightly, but is more than accurate enough for making these types of comparisons. The graph above, of course, uses a great deal of vertical exaggeration in order to fit all the data in a convenient space—but again this does not affect the comparison of one road to another.
In case you would like to check my work or calculate other average slopes, I have attached a spreadsheet of the raw data and all my calculations. I’m sure that your GIS Department could also verify the raw data itself, by starting with the maps and going through a similar process.
As an added bonus, we hereby unveil the latest Powder Mountain illustration, from the highly talented Devon Hoxer.
Do you see those kids, downhill from a careening truck, with failing brakes, on a "kid killing" general trajectory?
This topical political cartoon, we believe, provides the ideal finishing touch to Dan's most excellent submission:
And what say our gentle readers about all this?
36 comments:
Kudos to Dan S. for his concise information on the PM Road. The worry here is can the Weber County Commissioners even read? By their lack of response to many citizen's contacts, you wonder if they have passed basic reading and comprehension tests.
Just want to note this in Dan S's post:
In case you would like to check my work or calculate other average slopes, I have attached a spreadsheet of the raw data and all my calculations. I’m sure that your GIS Department could also verify the raw data itself, by starting with the maps and going through a similar process.
Providing the data and sources so all --- those who might agree and those who might disagree about Powder Mountain matters --- can, if they wish, check the data for themselves.
Be refreshing if the Ogden City Administration operated, as a matter of policy, in the same way: offering the data, research and sources it claims is behind its decisions [like the storied "Peterson Proposal" or the flatland gondola proposal] to be examined, vetted, checked by all, supporter and opponent alike.
It's how open government should operate. As a matter of policy.
lol you need a graph to know that?
"Therefore it is invalid for proponents to imply that the Powder Mountain road would present no more access and safety problems than these others."
Where do you get your data that says grade does present "more access and safety problems?"
I would submit that lesser grades allow for more speed and therefore cause "more access and safety problems."
Of course, I will provide no data supporting that statement thus making as equally valid or invalid as yours.
Perhaps someone has traffic volume and accident incident reports for all such roads.
I know this has come up before, but I can't even imagine what a development like this would do to the trafic use in Ogden Canyon.
I already feel bad for all the homeowners and users of the Canyon with its present level of use.
Here Ogden has this amazingly beautiful canyon, I believe one that is ranked in the top 10 in the nation to view the fall colors, and people are willing to turn it into a commuters highway.
What man won't do for a couple bucks!
"Huh?" said: "lol you need a graph to know that?"
And then he asks for supporting data to support the common sense inference that highly-pitched steep roads are more dangerous than flatter ones. He even advances the preposterous conjecture that steep roads are possibly more safe, presumably because white-knuckled drivers whose brakes are smoking and failing are more cautious on steep roads.
And then I turn the question on pore old Huh?
LOL! You need more data about that? Whatever happened to common sense in America?
Thanks for playin', gentle reader "huh?"
I'll just say that your WCF psuedonym handle seems to be particularly apt.
Dear "huh?":
Your hypothesis--that shallower grades are more dangerous because they allow driving at higher speeds--is so absurd that I hesitate to even respond. While I'd consider it a waste of time to try to gather data to test your hypothesis, I'd be glad to look at any such data you may have.
Meanwhile, I'll rely on my basic understanding energy, gravity, and thermodynamics. A 2800-foot descent releases enough energy to accelerate an object to a speed of nearly 300 miles per hour. To descend safely, this energy must instead be absorbed by the materials in the vehicle, especially the brake pads. If the descent is sufficiently shallow, there's enough time to dissipate the thermal energy and everything is fine. The steeper the descent, the more rapidly energy is deposited in the brakes and the greater the chance of their overheating.
This isn't just academic. Two of my friends nearly died on that road when their brakes overheated a few years ago. They survived in part because at the time there was almost no other traffic.
Two observations:
Within the past year a dump truck driver was killed coming down Trapper's Loop when he couldn't slow down and crashed into the fence at the intersection with Hwy. 39. What percent grade is Trapper's Loop?
Last night as I was driving West through Ogden Canyon I saw an 18 wheeler pulling tandem boxes, not just the usual one you see in the city. There is already far too much truck traffic (to say nothing of drivers hauling huge boats) going through the canyon.
I am amazed how few people are aware of using the lower gears in their vehicles. In fact, i do not recall ever seeing a sign on Powder Mt. Rd. advising using lower gears. Nearly everyone I follow on PMRd. is riding brakes all the way down and I am smelling them toasting most of the bottom half. Do they not teach this stuff in Driver Ed. Even my little Subee would wind up to 5000rpm at 45mph in second gear with no braking but I am in control. You have no control with brakes alone on this kind of road and are risking everything in ignorance. Almost no one realizes automatic transmissions also allow locking into a lower gear. I cannot imagine standing on the brakes for the complete descent of PMR.
Again ignorance of basic physics in our leaders and planners have us in a state of no leadership. This is evident all the way to the white house. A scientifically ignorant populace can be led like sheep into any old war or civic project or land development. I am sick of stupidity.
People almost die for all kinds of reasons...as an educator you shouldn't be so quick to dismiss it as absurdity.
Also, your understanding of thermodynamics "increases the chance" of overheating...failing to properly maintain your cars will do the same thing. So was your friends issue a function of the road? Or just laws of thermodynamics, that many people seem to deal with on a daily basis traveling up and down that road.
I am not a physicist but my understanding of human nature and a small amount of physics has taught me that the greater the potential for speed, the higher the likelihood of people traveling that speed. And the greater the speed people are traveling the higher potential for fatality and serious injury.
And then throw in per capital income as a factor and you just don't know what you will come up with.
"The biggest killer on our roads", the Road and Traffic Authority (RTA) of the Australian state of New South Wales (NSW), state that speeding (by which they mean travelling too fast for the prevailing conditions, in addition to speed above the specified speed limit[13]) is a factor in about 40 per cent of road deaths.[14] On the same webpage the RTA also state that "speeding increases the risk of a crash and the severity of the crash outcome".[14]
An early American study was described by Cierra, Berk, a retired British road engineer, which compared the circumstances around road deaths as reported in various American states (before the widespread introduction of 55 mph speed limits and drink-driving laws):[2]
'They took into account thirty factors which it was thought might affect the death rate. Among these were included the annual consumption of wine, of spirits and of malt beverages — taken individually — the amount spent on road maintenance, the minimum temperature, certain of the legal measures such as the amount spent on police, the number of police per 100,000 inhabitants, the follow-up programme on dangerous drivers, the quality of driver testing, and so on. The thirty factors were finally reduced to six on elimination of those which were found to have small or negligible effect. The final six were:
* (a) The percentage of the total state highway mileage that is rural.
* (b) The percent increase in motor vehicle registration.
* (c) The extent of motor vehicle inspection.
* (d) The percentage of state-administered highway that is surfaced.
* (e) The average yearly minimum temperature.
* (f) The income per capita.
'These are placed in descending order of importance. These six accounted for 70% of the variations in the rate.'
A 1985 study by K. Rumar, using British and American crash reports as data, found that 57% of crashes were due solely to driver factors, 27% to combined roadway and driver factors, 6% to combined vehicle and driver factors, 3% solely to roadway factors, 3% to combined roadway, driver, and vehicle factors, 2% solely to vehicle factors and 1% to combined roadway and vehicle factors.[3]
The U.S. Department of transportation's Federal Highway Administration have a webpage documenting a review of speed research.[12] The summary states:
* That the evidence shows that the risk of having a crash is increased both for vehicles travelling slower than the average speed, and for those travelling above the average speed.
* That the risk of being injured increases exponentially with speeds much faster than the median speed.
* That the severity of a crash depends on the vehicle speed change at impact.
* That there is limited evidence that suggests that lower speed limits result in lower speeds on a system wide basis.
* That most crashes related to speed involve speed too fast for the conditions.
* That more research is needed to determine the effectiveness of traffic calming.
A 1985 US study showed that about 34% of serious crashes had contributing factors related to the roadway or its environment. Most of these crashes also involved a human factor.[3] The road or environmental factor either contributed to the road user error, or did not allow room to recover from such an error.
So, it appears that many things contribute to accidents. And still I wonder the true implication regarding the grade of the road .
Steepiness:
Here's a clue. Find out how many roadway miles in New South Wales have a 14% or greater grade, then we'll talk.
If the roads don't exist, then people can't have accidents on 'em.
Until you find some 14% grades that exist on highways that take more traffic than the driveway of my house, you're just spouting nonsense with non-existent data.
Oh, Steepiness, let me do some of the homework for you.
Road grade standards are set by the American Association of State Highway and Transportation Officials (AASHTO).
Their current maximum grade standards are as follows:
PERMISSABLE ROAD GRADES
Arterial road 5 percent grade
Collector roads 8 percent grade
Other roads 10 percent grade
Thanks for playing. Here's a copy of our home game.
Monotreme....
After looking up fatal accidents on SR 158 for the last 15 years they appear to happen on the flat 50 mph section of the road. (oh yeah, people were estimated to be speeding in most those accidents.)
How do you then account for the apparent safety of the other section?
The point is you could argue that the road has 34 curves in it versus 22 on another road and therefore it is more dangerous. Just by saying that it doesn't make it true. Do the statistics bear it out????
Dan S. says it is absurd to even wonder out loud because he has already come to his conclusion whether it is true or not.
Much like those idiots on Fox News.
Ogdenlover: My best estimate is that the steepest part of Trapper's Loop has about a 9% grade. (This road is fairly new and the contours on the map have not been revised to show all the cuts and fills, so I got this number by averaging over a fairly long stretch--which is what the cuts and fills accomplish.) The total climb on Trapper's Loop from Pineview to the county line is just over 1000 feet, compared to the 2800-foot climb from Wolf Creek lodge to the top of Powder Mountain.
Tec: The friends I referred to are actually colleagues in the Physics Department at WSU, both with PhD's. I'm sure they were using engine braking but in my experience, engine braking is never enough when the grades exceed 6 or 8 percent.
Steepiness: Nice try at obfuscation but I don't think you're going to convince anyone that steep roads are safer than shallow roads.
Current Maximums? WTF? Yeah, that proves something.
Steepiness: I've already said that I'd be happy to look at any data showing that steep roads are safer than shallow ones. Show me your data on SR 158.
dap:
What's your point? I'm not responsible for grammatical errors in other people's documents.
Here's another document for your review, this one closer to home. It's from the Utah County Commissioners meeting, and it contains a discussion of maximum permissible road grades, road safety, and fire safety.
See #6 under "Regular Agenda"
You can stop spouting nonsense at any time, and you can also stop posting under three different names.
One can always try to confuse with distortions of data. Dan's point was simply that a 14% grade is a heck of a thing to use to serve a large residential area, and his data clearly bear that out based on the permissible safe maximums for such roads.
Anybody who has driven the Powder Mountain road also has a qualitative sense of its unsuitability.
Qualitative and quantitative data make Dan's points and are hard to argue against. My sense is those trying to do so here are grasping at straws.
Dan,
I wasn't referring to your friends in my statement but you have a lot of confidence that because they are phd's that they know how to use lower gears. I know that it gets frustrating driving down the road at 25 mph in second gear or even first in an automatic. Especially when you have a fool in a Dodge Ram pickup or such on your tail who gives no shit about smoking his brakes to oblivion. I know for a fact that the road can be driven with little braking if you use your lowest gearing. Anyway your statistics are well done and I totally agree that PMR is not suited to serve anything more than is already there. I know a lot of very intelligent people who are clueless about gear ratios and compression braking. Although it is poor form and bad taste to insist on the facts of whether they were using engine braking while their brakes failed but my sense is that they were not relying on lower gearing. Depending on the vehicle and the load, Lower gearing will dissipate at roughly half the energy generated descending that road.
Mountain driving lesson #2.
How many of you know what it is to "double clutch" and how to do it. This is another life saver that is not taught in any drivers ed. Mostly rally drivers use the technique.
When driving a manual and exceeding the range of a given gear for a downshift, ONLY a double clutch will get that tranny into that lower gear. My dad taught me to double clutch 40 years ago and explained exactly what happens when a trucker cannot get his transmission into a lower gear. It ain't pretty. Attention to gearing was never an issue before the introduction of the dumbing down automatic transmission. This allowed a whole class of clueless drivers to take to the road who have no sense of gearing and are not in tune to the sound of their engine. My mother knew about torque, gearing, compression braking, and could double clutch ...and all those things that will save your ass on a steep mountain grade.
Now who of you will explain to the audience how to pull off a smooth double clutch?
I'll add that the sound of a proficient double clutch down shift is sweet and controlled. Unlike the sound of a forced-by-the-synchromesh downshift to a idling engine.
Synchromesh is another nice upgrade to manual trannys that ultimately eliminated the skill necessary to operate a manual transmission with aplomb. A decent driver can drive a manual transmission without clutching at all and without grinding gears. Except for starting out from a dead stop, a clutch is basically useless.
Tec,
My confidence that my friends were using engine braking is not based solely on the fact that they know their physics. Although I don't remember the details of their story after the intervening years, I do remember that we discussed what happened in quite a bit of detail and I would have brought up engine braking even if they didn't. I use engine braking myself all the time on steep descents, so I would consider it remarkabe and memorable if they hadn't done so.
I greatly admire the ability of Steepiness/and his or her alter egos to cut and paste traffic data. The wonder, however, pertains to his or her affinity for onions. But please allow me to make an unassailable postulation that is as simple as death follows birth: Steep roads are more dangerous than flat ones, both for the navigator and those on the receiving end. Jesus Harold Christ.
THE SKI IS BEAUTIFUL BLUE
After a half century of driving now, cris-crossing the country several times,it occurs to me that I cannot recall a single runaway truck ramp anywhere that was not located on a steeply sloped highway. Nary a single one on the flat, as I recall.
This would seem to suggest that there is something inherently more dicey with respect to the consequences of brake failures at least about steeply sloped roads than about level ones, que no?
Curm:
The runaway truck ramps I've seen are on the steepest Interstate Highway grades, about 6% max as far as I have experienced.
Some of the last segments of the Interstate system, such as the approaches to the Eisenhower Tunnel under the Continental Divide, were completed late because of the difficulty of getting the grades right. Over near Morrison, on the approach to Denver heading east on I-70, there is a house that ended up with a semi's cab planted in its roof. The semi lost control -- on a 6% grade -- and ended up plunging over the dinky little guardrail and into the house.
I can't imagine a fire truck on a grade more than 10%, and neither can most fire chiefs. You can do a quick look around the Internets with A Google and find some discussions along these lines.
If safety is proportional to the steepness of a grade (with flat having the most accidents), it stands to reason that the safest grade of all would be a vertical drop.
Huh, duh, you are a geiger. geiger geiger, geiger.
I suppose if we carry you argument to conclussion adding 100 times more traffic to very steep narrow roadways increases their safety.
mono:
There are runaway truck ramps on other roads besides interstates. You pass a couple on state highways in Idaho taking the back way up to the Tetons [just east of Soda Springs] for example. As I recall, the grades are 6% there. There are many in the east too [in the Appalachians e.g.] on non-interstates too.
Damn. WEST of Soda Springs.
There are several truck run away ramps in California, some on I-15 and some on I-5. In case many do not know this fact, UDOT testified there is now way to modify 158 for those kind of ramps. I wonder if all those who feel the grades on 158 don't matter, would like to see their kids or Grandkids on that road when it is icy and crowded?
Runaway truck ramps are great if the truck can make it to them. Alot of times they go off the road or roll before they get to the ramp. One other thing is if they actually made it to the ramp, they've usually used the whole roadway to negotiatethe turns to get there.
What would it look like if the full development were to have to evacuate down the exsisting road because of fire? A very real possibility.
Happy times for a Californian Powder Mountain Tourist
Today I learned that another couple of friends once lost their brakes descending the Powder Mountain road. They assured me that they were using engine braking.
Don't have the time or interest to document the following, but I recall from the huge debates over increasing/decreasing speed limits that the number one factor in traffic accidents/injuries/deaths is not speed, not alcohol or drugs, not grades, not age--it is the number of miles driven. All other things being equal, more drivers, more miles, more accidents. Period. News articles in the past few days reported that traffic deaths have declined in about the same percentages that miles driven have declined due to high gas prices. Fewer miles, fewer deaths. Easy.
The Powder Mountain road is what it is, and it won't change. UDOT says so. The Powder Mountain developers' own figures BEFORE they added their 1800 new acres and their way-out-of-proportion new requested density figures projected traffic loads some eight to ten times current loads. That WILL translate, if they get anywhere near their requested density, a minimum of eight to ten times more driver miles, accidents, injuries, and deaths. Same road; same grades; more deaths. Peachy. Thanks, developers.
I live right at the bottom of the steep part of the road. Any day I'm out in my yard, I can smell the burning brakes.
My experience is that even people who are intelligent and are experienced drivers do not know how to drive that road safely. I have driven that road countless times. I use first gear and crawl my vehicles down at less than 20 MPH. If I use even second gear, my rpms go up too high and I end up having to use my brakes to the point of burning. It doesn't bother me to go so slowly when there are very few people on the road. But when there are others flying down, braking behind me, and then passing, I shudder to think of it with many people on the road at the same time.
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