Traffic Signals

There are two basic types of traffic signals in Appleton. These are "interconnected" and "traffic actuated".

Most of Appleton's signals are inter-connected, which means that there is a relationship between the beginning of the green lights in a given area.  At any given time of the day a green light will always come on X-many seconds before or after a nearby intersection. Since traffic patterns change at different times of the day, there are separate timing plans for morning, midday and afternoons.  This is done to promote vehicle progression and reduce stops and delays.  On a one-way street it is possible to have very good progression.  This is not as easy on a normal Appleton two-way street.  We have various computer programs to assist us in establishing the best timing of a route based on traffic volumes, speed limits, and distance between signals.

Some of Appleton's signalized intersection are "traffic actuated" or "semi-traffic actuated". These intersections have magnetic "loops" in the pavement that sense the presence of a vehicle.  You may have noticed that the turn arrow on College Avenue at Memorial/Richmond does not always come on.  This is an example of a semi-actuated intersection.  The detector loops are placed in the left turn lanes in a location so as to engage the turn arrow when three or more vehicles are stacked up in the turn lane.  When two or less vehicles are present the time allotted to the arrow is added to the through green time.

Traffic signals in Appleton are installed for various reasons.  Two of the main reasons are to promote safety and lesson delay for pedestrians and drivers.  The Traffic Engineering Division receives many requests to install traffic signals at a specific location.  In many instances these requests come because some motorists are "having a problem" at a location.  Whenever this office receives a complaint, a complete signal "study" is done.

Appleton utilizes criteria established by the Federal "Manual on Uniform Traffic Control Devices" to determine the need for a traffic signal.  These were developed by national organizations from data of cities, counties, and states.  The criteria are based on vehicle and pedestrian traffic volumes, safety records, and whether a signal can be synchronized with other signals on a street to provide constant flowing traffic.

According to the criteria, advantages of traffic signals are:

• Signals can provide for orderly movement of traffic.
• Reduce the frequency of certain type of accidents, especially the right-angle type.
• Under ideal conditions, signals can be coordinated to provide for nearly continuous traffic movement at a definite speed along a given route.
• Signals can stop traffic at intersections so that other vehicles and pedestrians may cross.

Disadvantages of traffic signals are:

• May cause additional stops and delays for the major traffic carrier, and may increase delay on the side street that signal was installed to benefit. This increases both noise and air pollution.
• Motorists may detour around arterial streets with signals and use neighborhood streets instead.
• Increase the frequency of certain types of accidents, especially rear-end types.
• Cost: $60,000 to install and $2,000 to $2,500 per year for maintenance.

In some cases the criteria for installing a traffic signal may be met and the recommendation from this department will be to "not" install a signal.  Those criteria are minimum values, and it may be decided that the disadvantages outweigh the advantages.