Traffic signs, pavement markings and traffic signals are the result of an engineering study conducted by the Road Commission. The Road Commission has the responsibility and authority to place traffic signs and traffic signals at locations that have met a specific list of warrants or guidelines that are found in the Michigan Manual of Uniform Traffic Control Devices (MMUTCD). To be effective, traffic controls should meet five basic requirements:
1. Fulfill a need,
2. Command attention,
3. Convey a clear, simple meaning,
4. Command the respect of road users, and
5. Give adequate time for proper response.
Specific warning signs for schools, playgrounds, parks and other recreational facilities where persons are gathered and may be vulnerable are listed in the Michigan Manual of Uniform Traffic Control Devices and available for use where clearly justified. The Michigan Manual has lists of traffic signs that can be used and also their proper size and installation. The Manual also describes pavement markings and their specific uses.
A traffic engineer makes a determination of whether a signal is or is not “warranted” based on standards of the Michigan Manual of Uniform Traffic Control Devices (MMUTCD). This manual identifies 9 warrants that may be reviewed in determining whether a signal should be installed.
The warrants that receive the closest review, however, are minimum vehicular volume, interruption of continuous traffic, and accident experience. The first relates to whether there is sufficient traffic coming out of the side street in question to consider stopping traffic on the main road. The second relates to whether or not the traffic is too heavy on the main road for motorists from the side street to pull out. The last is an indication that traffic on the side street is having difficulty getting out, causing right-angle accidents to occur.
The Road Commission continuously reviews intersections for all types of traffic control devices.
Speed limits are established in accordance with the Michigan Vehicle Code and State Legislature.
Currently, regulatory speed limits are set by State Statue at a maximum 55 mph on county roads or 25 mph for business and residential districts. These speed limits are generally not posted on county roads.
Regulatory speed limits can be modified based on a unanimous recommendation from a traffic survey team consisting of representatives from the Michigan State Police, Road Commission, and Local Township. The recommendation is based primarily on results of a traffic engineering study that includes the collection of speed data, review of the crash history, and roadway characteristics.
The Lansing office of the State Police has to accept the recommendation of the survey team in order to establish a modified speed limit. Once approved, signs for the new speed limit can be posted.
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Stop signs installed at the wrong place for the wrong purpose usually create more problems than they solve. One common misuse of stop signs is to arbitrarily interrupt traffic, either by causing it to stop or by causing such an inconvenience that motorists are forced to use other routes.
Traffic studies indicate that there is a high incidence of intentional violations where stop signs are installed as “nuisances” or “speed breakers.” The studies also show that drivers increase their speeds between unwarranted stop signs to make up for the lost time. Based on these studies and the increased speeds of drivers on streets with unwarranted stop signs, the Michigan Manual of Uniform Traffic Control Devices (MMUTCD) clearly states that “Stop signs shall not be used for speed control.”
A stop sign placed at the right place and under the right conditions, tells drivers and pedestrians who has the right of way.
A speed bump is a bump of asphalt about a foot wide, 3 to 4 inches high, and placed laterally across the traveled portion of the road. However, the speed bump poses as an increased hazard to motorists, the cause of an undesirable increase in noise, and a real problem for snow removal.
The purpose of a speed bump is to make the ride over it uncomfortable for the driver, encouraging him/her to reduce their speed. With the various vehicle suspensions and wheel bases, the speed bump has shown an inability to successfully control speeds.
Speed bumps can cause maintenance problems to any vehicle and increase response time for emergency services. Because speed bumps have considerable potential for liability suits, Michigan has officially rejected them as a standard traffic control device on public streets.
The control of speeding in neighborhoods is a widespread concern which requires compliance by residents, patience and persistent effort by law enforcement – not speed bumps.
At first consideration, it might seem that a “children at play” sign would provide some safety for youngsters playing in a neighborhood. Unfortunately, this type of sign encourages parents to believe that children have an added degree of protection; which the signs do not and cannot provide.
Studies have shown that this type of sign provides no evidence of reducing pedestrian crashes or vehicles speeds. Obviously, children should not be encouraged to play in the roadway. The “children at play” sign is a direct and open suggestion that it is acceptable to do so.
Federal standards discourage the use of this sign and they are not even recognized in Michigan’s traffic sign manuals. As an alternative, the Road Commission strives to remove vision obstructions to provide a safe roadway for both pedestrians and motorists.
Can I place Handicap, Deaf, Blind, Special Needs Child, or Pedestrian Area warning signs on my street?
The use of Handicap, Deaf, Blind, Special Needs Child, or Pedestrian Area warning signs is limited to situations and locations meeting approval of the Ottawa County Road Commission.
Requests for such signs shall be made in writing and include a physician’s certification/letter indicating extent of handicap. The requesting party will also need to advise the Road Commission on an annual basis as to the continued need of these warning signs.
The number and location of these warning signs will be determined by the Road Commission and generally will be limited to the roadway serving the handicap person’s residence.
The installation cost will be the responsibility of the requesting resident and all costs to maintain sign(s) will be paid by the Road Commission.
When a construction project impacts the normal use of a county road, warning devices such as barrels, signs, and arrow boards are placed in accordance with a traffic control plan.
The basic objective of a traffic control plan is to permit construction work within the county road right of way in an efficient and effective manner, while maintaining a safe, uniform flow of traffic.
The construction work and motorists, bicycles, and pedestrians traveling through the work zone must be given equal consideration when developing a traffic control plan. Each traffic control plan is developed to be consistent with the Manual on Uniform Traffic Control Devices (MUTCD).
The Road Commission relies on the cooperation of various news media in publicizing the implementation of major road closures and detours as a method of keeping the public well informed.
In general, left turn phasing has popular public support while the traffic engineering community, because of inherent traffic delays and possible increase in other than head-on-left-turn crash experience, is typically less enthusiastic about its use unless a significant need can be established. Some factors to be considered when evaluating the need for left turn phasing include: traffic volumes, intersection capacity, pedestrian volumes, traffic signal progression, crash history and left turn motorist delay.
There are two modes of left turn signal control: permitted mode and protected mode. In the permitted mode a left turning motorist is provided either a flashing red ball or a flashing yellow arrow. The driver is permitted to turn left whenever there is an adequate gap in opposing traffic. In the protected mode a left turning motorist is provided a green arrow display while opposing traffic is stopped.
Most left turn signal operations consist of a combination of the permitted and protected modes. However, there are instances where a left turn signal is operated in the protected only mode and left turn vehicles are not given the opportunity to make a permissive left turn. The considerations for installation of a protected only left turn signal include:
- High left turn traffic volume
- High opposing through volume
- An existing crash history
- Limited sight distance
- High speed opposing through traffic
- Left turning vehicles must cross 3 or more lanes of opposing through traffic
- There are multiple left turn lanes
Note: The flashing yellow arrow is now the national standard for permissive left turn signal operation. All new left turn signal installations with a permissive mode will have the flashing yellow operation. In addition, existing flashing red balls will be replaced with flashing yellow arrows as traffic signals are upgraded/modernized.