Why is the city council allowing the county to extort us for about $400,000 for each new county traffic signal? …
The Federal Highway Administration established a national uniform standard for all Traffic Control Devices in United States in 1977. These standards were mandated by congress to assure uniformity in the application of traffic control throughout the country. Originally States and other government sub-divisions that did not comply with the standards could have loss their federal aid funds. Today they would lose their wallets via tort claims in the courts
The Traffic Signal Standard has 8 Warrants
An engineering study of traffic conditions, pedestrian characteristics, and physical characteristics of the location is performed to determine whether installation of a traffic control signal is justified at a particular location. The investigation of the need for a traffic control signal includes an analysis of the applicable factors contained in the following traffic signal warrants and other factors related to existing operation and safety at the study location: The satisfaction of a traffic signal warrant or warrants does not in itself require the installation of a traffic control signal
Warrant 1, Eight-Hour Vehicular Volume.
Warrant 2, Four-Hour Vehicular Volume.
Warrant 3, Peak Hour.
Warrant 4, Pedestrian Volume.
Warrant 5, School Crossing.
Warrant 6, Coordinated Signal System.
Warrant 7, Crash Experience.
Warrant 8, Roadway Network.
I do not have access to any traffic engineering data for the Crane Lakes intersection, however I pass through that intersection on many occasions. Based solely on observations I would assume that the existing traffic parameters at the intersection may only be applicable to 3 of the above 8 warrants. Warrants 1; 6 and 7 and perhaps 3
Warrant #1 8-Hour Vehicular Volume
Although there are other parameters in this warrant, it is basically satisfied if there is an hourly vehicular volume of : 500 vehicles on the major street (Taylor Rd,) and 150 vehicles on side street OR 750 vehicles on Taylor and 75 vehicles on the side street. These hourly volumes must exist for any 8 hours of an average day ( normally 4 hours in the AM peak and 4 hours in the PM peak)
Based on my cursory observations of the vehicular volume on that section of Taylor Road, Warrant #1 would not be satisfied ( i.e. about 10 vehicles per minute for 8 hours). The county traffic engineering division will install electronic counters to collect the volume data at that intersection. However, if they are a viable organisation they already have that volume data on file.
Warrant #6, Coordinated Signal System
Progressive movement in a coordinated signal system sometimes necessitates installing traffic control signals at intersections where they would not otherwise be needed in order to maintain proper platooning of vehicles.
Adjacent traffic control signals do not provide the necessary degree of platooning and the proposed and adjacent traffic control signals will collectively provide a progressive operation.
The Coordinated Signal System signal warrant should not be applied where the resultant spacing of traffic control signals would be less than 1,000 ft.
However, this warrant may not be satisfied here because there would be no coordinated signals on Taylor Rd. west of this intersection. Thus, no platooning from the west. And very little vehicular platooning from the east due to the light volume.
Warrant #7, Crash Experience
The Crash Experience signal warrant conditions are intended for application where the severity and frequency of crashes are the principal reasons to consider installing a traffic control signal.
The need for a traffic control signal shall be considered if an engineering study finds that all of the following criteria are met:
- Adequate trial of alternatives with satisfactory observance and enforcement has failed to reduce the crash frequency; and
- Five or more reported crashes, of types susceptible to correction by a traffic control signal, have occurred within a 12-month period, ( Traffic Signals tend to reduce right-angle collisions but increase the frequency of rear-end collisions)
- For each of any 8 hours of an average day, the vehicles per hour (vph) is 80 percent of Warrant #1 above.
Option for Warrant 7:
If the posted speed limit exceeds 40 mph, or if the intersection lies within the built-up area of an isolated community having a population of less than 10,000, the traffic volumes in the 56 percent may be used in place of the 80 percent above.
I think I heard a representative of Crane Lakes say there were 17 accidents in ten years at this intersection, if so, satisfying this warrant may not be possible.