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?
