Russ Steele
In his President's Message in the February 2006 - April 2008 News letter, the new Nevada City Chamber President Jeff Ackerman makes the following statement about the freeway between Grass Valley and Nevada City.
"You could make a pretty good case today that the freeway was a mistake and that simple boulevard between Grass Valley and Nevada City would have actually relieved the bottleneck we see in the Glenbrook Basin today."
Interesting observation, let see how well it holds up under some real world analysis.
Checking my 13th Edition of the Fundamentals of Traffic Engineering we find the following maximum service volume at levels of service shown for 70 mph on controlled access freeway and 60 mph for two lane highways with uncontrolled access. Since the traffic charts are for higher speeds, the actual through put would be less for the SR-49/20 freeway with a speed limit of 55 mph. But, close enough.
To help compare the results I have extracted a small chart from Page 8-3.
Also included in the graphic is the peak hour traffic count on freeway between Nevada City and Grass Valley in both directions from the Caltrans traffic count data base for 2006. As you can see, the current peak hour traffic is between service levels A and B. However if we had an uncontrolled access simple boulevard, two lanes wide, the road would be unable to carry the current freeway traffic load. If it were a simple boulevard, four lanes wide, the service level would be between service level D and F, closing in on capacity. Since between 2003 and 2006 the peak hour traffic grew about 150 vehicle per year, and if the same rate were to apply for the next three years, in 2011 the simple four lane boulevard would be in failure mode, it would be at capacity.
I think based on the above figures the case can be made that a freeway between Nevada City and Grass Valley was the right decision. The real questions is was it the right design?
The current freeway design would never be approved under todays design standard. In a lucid moment at a conference a Caltrans engineer who worked on the design explained the flaws, including the problems in Hill Flat and Glenbrook. He said, if it were designed today (1994) the freeway would go around both Nevada City and Grass Valley, not through the cities.
While we find the current design troublesome, I think a freeway that went around the city could have some long term economic impacts, fewer tourist and less commerce, as drivers felt no need to stop. We are better off to improve the freeway we have, rather than wish for something that would have never worked, no matter how romantic it sounds.
