CAN THE CITY POST A LOWER SPEED LIMIT ON MY STREET TO SLOW DOWN TRAFFIC?

Speeding is a problem that plagues most all of Vacaville's neighborhoods. As such, Traffic Engineering works closely with the Police Department to educate drivers and enforce speed laws in many areas of town.

Some widely held misconceptions are that speed limit signs lower the speed of traffic, reduce accidents and increase safety. However, most drivers pay little attention to speed limit signs, and drive at a speed that they consider comfortable. A driver's speed is more influenced by the appearance of the roadway and the prevailing traffic conditions than by the posted speed limit. In addition, research studies show there is no direct relationship between posted speed limits and the frequency of accidents.  Non-the-less, posting appropriate speed limits establishes a steady flow of traffic, and simplifies the job of enforcement.

The City of Vacaville has posted speed limits that range from 25 to 65 miles per hour. These speeds are based on Traffic Engineering Surveys that take into consideration the roadway conditions, accident records, and the speed of drivers.  The maximum speed limit for any passenger vehicle is 65 miles per hour.

All speed limits below 65 are either set by the California Vehicle Code (e.g. 25 miles per hour in business and residential areas, and 15 miles per hour in alleys), or have been established through a Traffic Engineering Survey. The speed limit is not always posted, but drivers are required to know to drive at a safe speed; this is referred to as the "Basic Speed Law" in the Uniform Vehicle Code.  

WHAT ARE THE CRITERIA FOR PUTTING IN A STOP SIGN?

There are two types of stop conditions at any intersection: Two-way Stop (only the minor street is stopped); and Multi-way Stop (both streets, i.e. all four legs, are required to stop). Stop signs should not be viewed as a cure-all for solving all traffic safety problems, but when used properly stop signs are a useful traffic control device, and enhance safety for all roadway users.

Many people request stop signs to be installed for the purpose of lowering speeds. However, the true purpose of a stop sign is solely to assign right-of-way at an intersection.  Various research studies indicate that stop signs do not reduce the overall speed of traffic.   As such, when stop signs are installed strictly for the purpose of slowing traffic, the speeds are reduced in the vicinity of the stop sign, but tend to be higher between the intersections. Also, the overuse of stop signs may cause general contempt for all traffic control devices, often with tragic consequences. 

The City of Vacaville is required by law to comply with Federal and State guidelines when installing traffic control devices such as stop signs. For example, multi-way stop signs are installed at an intersection only after a Traffic Engineering study is completed which considers accident history, traffic volumes, speed of traffic, and sign distance problems.

Traffic accidents could be reduced, in some cases, with simple measures like improving visibility by prohibiting parking close to the intersection. However,  If you have a question regarding a particular intersection, please contact the Traffic Engineering Division at (707) 449-5170.

The purpose of a traffic signal is to assign right-of-way to opposing movements of traffic at an intersection. As such, it may be necessary to install a traffic signal if the traffic volume increases and four-way stop signs do not lessen problems. However, improperly placed traffic signals can cause an increase in traffic accidents, particularly rear end collisions. And, pedestrians can gain a false sense of security from crosswalks and red lights, which may result in an increase in pedestrian accidents.

Before installing a traffic signal at an intersection, traffic engineers have to evaluate the following questions:

1. Does the volume of vehicles entering an intersection create confusion or congestion?
2. Is there so much traffic on main streets that it may be dangerous for traffic on side streets to cross? Are accidents the result of this condition?
3. Is there an increasing demand for pedestrians to cross main streets?
4. Does the number of school children crossing a busy street create confusion, congestion, or hazardous conditions?
5. Will the installation of a signal reduce overall congestion?
6. Does the accident history indicate that a signal will reduce the number of
   accidents at an intersection?

Traffic engineers use national standards to evaluate an intersection that may need a traffic signal. Properly placing traffic signals will decrease accidents and improve traffic flow.

Traffic engineers and technicians are constantly upgrading the signal systems in the City. Traffic flow is being improved on major arterials in Vacaville by coordinating traffic signals, which will allow vehicles to travel along the signalized streets with fewer stops.  If you think there is an intersection that should be studied for a traffic signal; or, if you notice an existing traffic signal that is not operating correctly, please contact the Traffic Engineering Division at (707) 449-5170.

Speed bumps are not recognized by the State of California as an official traffic control device, and as such the City of Vacaville does not use them on public streets.

Additional reasons for not using speed bumps  are directly related to the experience of others.  For example, many cities have experimented with speed bumps, but have noted a problem with their overall safety and effectiveness.  Speed bumps have been found to cause injuries in case of accidents, increase noise levels in neighborhoods, and significantly reduce the response time of emergency vehicles. Also, no single design of speed bumps has been found to be successful in safely controlling the speed of all types of passenger vehicles.   Furthermore, the Courts have made public agencies liable for the personal injuries related to the use of speed bumps.

Parents who are concerned about the safety of their children sometimes request that the City install "Children at Play" signs, believing that these signs will provide added protection to their children near roadways. However, studies have shown that posting "Children at Play" signs in residential areas does not reduce vehicle speeds or pedestrian accidents. In addition, the use of these signs creates a false sense of security in both parents and children.

Of particular concern is that "Children at Play" signs may suggest to children that it is acceptable to play in City streets, which could lead to devastating results. And, in the case of a vehicle/pedestrian accident, the pedestrian always loses.  It is important to teach children to respect moving vehicles and how to be a safe pedestrian. Most importantly, children should not play in or near roadways.

"Children at Play" signs are not recognized by Federal or State law as official traffic control devices, and therefore are not installed by the City of Vacaville on public streets.  

The City of Vacaville receives many requests for installing crosswalks on City streets. Crosswalks can either be "marked" with painted lines of white or yellow, or left "unmarked" at an intersection.

The purpose of a "marked" crosswalk is to encourage pedestrians to use a particular crossing.  Normally, crosswalks are "marked" at places where there is an abundance of pedestrian movement, at a signal, and where pedestrians cannot recognize a proper place to cross.   However, if "marked" crosswalks are not frequently used by pedestrians, then drivers tend to forget that they exist. As a result, accidents can occur when pedestrians rely on crosswalks to provide them with a safe barrier from traffic.

It is the City's policy not to install "marked" crosswalks mid-block (between intersections), except where the crosswalk is in front of, or directly adjacent to, schools.  These crosswalks are painted yellow and imited to those locations where a crossing guard is posted during school hours.

As an added note.....National studies have shown that marked crosswalks actually increase the risk to pedestrians crossing the street. In these studies, it was found that pedestrians are given a false sense of security at "marked" crosswalks, and tend to blindly cross the street, trusting the crosswalk to keep them out of harm's way. As such, it is important that pedestrians remain attentive and cautious of on-coming vehicles on a roadway before crossing a street, regardless of the presence, or lack of, a crosswalk.

HOW DO THE PEDESTRIAN SIGNALS (WALK/DON'T WALK) WORK? THEY
ALWAYS SEEM TO CHANGE BEFORE I GET A CHANCE TO CROSS THE STREET.

In Vacaville, pedestrian signals are included at any signalized intersection that is
intended to accommodate pedestrian traffic.  Pedestrian signals are carefully designed to provide reasonable time for crossing a specific street safely. 

Transportation engineers around the world are moving towards symbol signs in place of word signs.  Symbols are easier for people to comprehend in a shorter amount of time, and do not present a language barrier for non-English speaking pedestrians.  Pedestrian signal indications should be interpreted in the following manner:

1. A steady white color WALKING PERSON (symbolizing WALK) signal indication means that you may begin crossing.  (In Vacaville, the “WALK” indications typically displays for 6 seconds).

2. A flashing orange color UPRAISED HAND (symbolizing DON’T WALK) signal indication means it is too late to leave the curb; however, any pedestrian already off the curb may proceed across to a sidewalk or safety island.  In Vacaville, the duration of the flashing display is determined using the distance that the pedestrian has to cross, typically with a standard walking rate of 4 feet per second.

3. A steady orange color UPRAISED HAND (symbolizing DON’T WALK) signal indication is a warning to pedestrians not to leave the curb enter the roadway as cross traffic will be receiving a green light to proceed.

Pedestrians should only leave the curb during the “WALK” period.  Once the pedestrian signal changes to a steady burning “DON’T WALK” it is no longer safe for a pedestrian to be in the crosswalk.  Regardless of what the symbol shows on the pedestrian signal, pedestrians should be cautious when crossing busy intersections.