Potential MUTCD Criteria for Selecting the Type of Control for Unsignalized Intersections (2015)

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6 CHAPTER 2: REVIEW OF POLICIES AND GUIDELINES BACKGROUND This chapter summarizes the findings from the review of policies and guidelines used by state and local transportation agencies. It opens with a broad overview of the criteria in the current edition of the MUTCD and summarizes previous and anticipated changes to the sections of interest. MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES 2009 MUTCD Sections 2B.04 to 2B.09 The 2009 MUTCD (1) provides guidance on application of YIELD signs (Sections 2B.08 and 2B.09) and STOP signs (Sections 2B.05 through 2B.07) on one or more approaches to an intersection. STOP and YIELD signs are also discussed in Section 2B.04, which covers right of way at intersections. History of Existing MUTCD Sections 2B.04 through 2B.09 The current MUTCD (1) has been revised several times including in the 1948 (2), 1961 (3), 1988 (4), 2000 (5), and 2003 (6) editions. The following subsections address the major revisions that have been made to the MUTCD up to and including the 2009 edition (1). Right of Way at Intersections The 2009 MUTCD includes a new section addressing right of way at intersections pertaining to both STOP and YIELD signing. The new section provides a general overview of the criteria to be considered for any intersection control, using a combination of new text and text moved from other sections of the previous manual. The 2009 MUTCD provisions include the following: Engineering judgment should be used to establish intersection control. The following factors should be considered: A. Vehicular, bicycle, and pedestrian traffic volumes on all approaches; B. Number and angle of approaches; C. Approach speeds; D. Sight distance available on each approach; and E. Reported crash experience. YIELD or STOP signs should be used at an intersection if one or more of the following conditions exist:

7 A. An intersection of a less important road with a main road where application of the normal right-of-way rule would not be expected to provide reasonable compliance with the law; B. A street entering a designated through highway or street; and/or C. An un-signalized intersection in a signalized area. In addition, the use of YIELD or STOP signs should be considered at the intersection of two minor streets or local roads where the intersection has more than three approaches and where one or more of the following conditions exist: A. The combined vehicular, bicycle, and pedestrian volume entering the intersection from all approaches averages more than 2,000 units per day; B. The ability to see conflicting traffic on an approach is not sufficient to allow a road user to stop or yield in compliance with the normal right-of- way rule if such stopping or yielding is necessary; and/or C. Crash records indicate that five or more crashes that involve the failure to yield the right-of-way at the intersection under the normal right-of-way rule have been reported within a 3-year period, or that three or more such crashes have been reported within a 2-year period. STOP Sign Applications The initial criteria for STOP sign applications were included in the 1948 edition (2) and remained the same through the 2003 edition (6). Those criteria considered the following conditions:  Intersection of a less important road with a main road where application of the normal right- of-way rule would not be expected to provide reasonable compliance with the law.  Street entering a through highway or street.  Unsignalized intersection in a signalized area.  High speeds, restricted view, or crash records indicating a need for control by a STOP sign. The 2009 MUTCD (1) relocated the above criteria into the new Section 2B.04 and added the following for STOP sign applications: The use of STOP signs on the minor-street approaches should be considered if engineering judgment indicates that a stop is always required because of one or more of the following conditions: A. The vehicular traffic volumes on the through street or highway exceed 6,000 vehicles per day; B. A restricted view exists that requires road users to stop in order to adequately observe conflicting traffic on the through street or highway; and/or C. Crash records indicate that three or more crashes that are susceptible to correction by the installation of a STOP sign have been reported within a

8 12-month period, or that five or more such crashes have been reported within a 2-year period. Such crashes include right-angle collisions involving road users on the minor-street approach failing to yield the right-of-way to traffic on the through street or highway. Four-way or Multi-way STOP Signs The application of four-way or multi-way STOP signs was added to the 1961 MUTCD (3) and remained basically the same through the 1988 edition (4). The following conditions may warrant a multi-way STOP sign installation in the 1988 edition: 1. Where traffic signals are warranted and urgently needed, the multi-way stop is an interim measure that can be installed quickly to control traffic while arrangements are being made for the signal installation. 2. An accident problem, as indicated by five or more reported accidents of a type susceptible of correction by a multi-way stop installation in a 12-month period. 3. Minimum traffic volumes: a. The total vehicular volume entering the intersection from all approaches must average at least 500 vehicles per hour for any 8 hours of an average day, and b. The combined vehicular and pedestrian volume from the minor street or highway must average at least 200 units per hour for the same 8 hours, with an average delay to minor street vehicular traffic of at least 30 seconds per vehicle during the maximum hour, but c. When the 85th-percentile approach speed of the major street traffic exceeds 40 miles per hour, the minimum vehicular volume warrant is 70 percent of the above requirements. The 2000 (5), 2003 (6), and 2009 (1) MUTCD editions revised Item 3a above on minimum volumes and added other conditions that could be considered. The criteria presently read as follows: The following criteria should be considered in the engineering study for a multi- way STOP sign installation: A. Where traffic control signals are justified, the multi-way stop is an interim measure that can be installed quickly to control traffic while arrangements are being made for the installation of the traffic control signal. B. Five or more reported crashes in a 12-month period that are susceptible to correction by a multi-way stop installation. Such crashes include right- turn and left-turn collisions as well as right-angle collisions.

9 C. Minimum volumes: 1. The vehicular volume entering the intersection from the major street approaches (total of both approaches) averages at least 300 vehicles per hour for any 8 hours of an average day; and 2. The combined vehicular, pedestrian, and bicycle volume entering the intersection from the minor street approaches (total of both approaches) averages at least 200 units per hour for the same 8 hours, with an average delay to minor-street vehicular traffic of at least 30 seconds per vehicle during the highest hour; but 3. If the 85th-percentile approach speed of the major-street traffic exceeds 40 mph, the minimum vehicular volume warrants are 70 percent of the values provided in Items 1 and 2. D. Where no single criterion is satisfied, but where Criteria B, C.1, and C.2 are all satisfied to 80 percent of the minimum values. Criterion C.3 is excluded from this condition. Other criteria that may be considered in an engineering study include: A. The need to control left-turn conflicts; B. The need to control vehicle/pedestrian conflicts near locations that generate high pedestrian volumes; C. Locations where a road user, after stopping, cannot see conflicting traffic and is not able to negotiate the intersection unless conflicting cross traffic is also required to stop; and D. An intersection of two residential neighborhood collector (through) streets of similar design and operating characteristics where multi-way stop control would improve traffic operational characteristics of the intersection. YIELD Sign Applications The YIELD sign was added to the MUTCD in the 1961 edition (3), and the criteria for application remained the same through the 1988 edition (4), with the following conditions: 1. On a minor road at the entrance to an intersection where it is necessary to assign right-of-way to the major road, but where a stop is not necessary at all times, and where the safe approach speed on the minor road exceeds 10 miles per hour. 2. On the entrance ramp to an expressway where an acceleration lane is not provided. 3. Within an intersection with a divided highway, where a STOP sign is present at the entrance to the first roadway and further control is necessary at the entrance to the second roadway, and where the median width between the two roadways exceeds 30 feet. 4. Where there is a separate or channelized right-turn lane, without an adequate acceleration lane.

10 5. At any intersection where a special problem exists, and where an engineering study indicates the problem to be susceptible to correction by the use of the YIELD sign. The 2000 (5), 2003 (6), and 2009 (1) MUTCD editions consolidated the criteria into four items for consideration as follows: YIELD signs may be installed: A. On the approaches to a through street or highway where conditions are such that a full stop is not always required. B. At the second crossroad of a divided highway, where the median width at the intersection is 30 feet or greater. In this case, a STOP or YIELD sign may be installed at the entrance to the first roadway of a divided highway, and a YIELD sign may be installed at the entrance to the second roadway. C. For a channelized turn lane that is separated from the adjacent travel lanes by an island, even if the adjacent lanes at the intersection are controlled by a highway traffic control signal or by a STOP sign. D. At an intersection where a special problem exists and where engineering judgment indicates the problem to be susceptible to correction by the use of the YIELD sign. The 2009 edition (1) of the MUTCD also added a fifth item to the YIELD options as follows: E. Facing the entering roadway for a merge-type movement if engineering judgment indicates that control is needed because acceleration geometry and/or sight distance is not adequate for merging traffic operation. Potential Change to MUTCD NCUTCD recently reviewed the term “approximately equal” as used within the multi-way stop control section. The committee presented the following discussion (7): The support statement in Section 2B.07 states: Multi-way stop control is used where the volume of traffic on the intersecting roads is approximately equal. How do we define the term “approximately equal”? Section 2B.07 guidance provides criteria in paragraph C as follows:  Vehicular volume entering the intersection from the major street approaches (total of both approaches) averages at least 300 vehicles per hour for any 8 hours of an average day; and  The combined vehicular, pedestrian, and bicycle volume entering the intersection from the minor street approaches (total of both approaches) averages at least 200 units per hour for the same 8 hours.

11 This language provides a reasonable indication that approximately equal at the minimum value is 200 units on the minor street and 500 units in total volume. This is a ratio of 40% minor street volumes to the total volume. However, this does not provide a definition or indication of the maximum volumes on either the major or minor street. It only deals with the minimum volume end of the spectrum. The Highway Capacity Manual (HCM) does provide some insights in Chapter 17, Unsignalized intersections. The critical criteria may be found in the critical gap and delay studies. The delay study along with the level of service at the intersection must be factored in along with the turning volumes. The MUTCD already has language in this section indicating a delay of at least 30 seconds for the minor street approach during the highest hour. The principal elements affecting selection of intersection traffic control are:  Functional classification of each intersecting street  Peak hour traffic volumes (vehicular and pedestrian)  Crash History  Intersection geometrics  Sight Distance Functional classification and traffic volumes are the two parameters that largely influence the question of “approximately equal volumes”. The classification of intersecting legs should also be factored in before electing to use a multi-way stop control.  At a local-local intersection, no control or yield control is more appropriate.  At a local-collector intersection, a yield or one- or two-way stop control is more appropriate.  At a local-major intersection a one- or two-way stop control is more appropriate.  Where a collector intersects with a collector with medium vehicular activity level, an all-way stop control may be appropriate.  Where two major roadways intersect, an all-way stop control may be appropriate or signal. ITE studies have demonstrated that when the 8 hour minimum volumes from all approaches of 180–400 vehicles per hour with at least 40% from the minor or secondary street would then provide the point at which a multi-way stop could be considered. More recent studies have shown that when the 8 hour minimum volumes from all approaches of 500 vehicles per hour with at least 40% from the minor or secondary street would provide the point at which a multi-way stop could be considered, in addition to the sight distance criteria.

12 Based upon these considerations, the following suggested change was made and endorsed by the full NCUTCD within item number 2 of the minimum volume criteria: 2. The combined vehicular, pedestrian, and bicycle volume entering the intersection from the minor street approaches (total of both approaches) is at least 40% of the total vehicular volume entering from all approaches and averages at least 200 units per hour for the same 8 hours, with an average delay to minor- street vehicular traffic of at least 30 seconds per vehicle during the highest hour;… Another recent effort is to develop revisions to the MUTCD to define the application of traffic control devices to sites open to public travel. Several changes are being considered by the NCUTCD for sites open to public travel, such as sign size or the use of a STOP or YIELD sign at the end of a parking lot aisle. There is also an ongoing effort to consider reorganization of the MUTCD to group existing sections into chapters by topic area. The purpose of this effort is to enhance the usability of the MUTCD in both the print edition and the electronic edition. REVIEW OF STATE AND LOCAL DOCUMENTS The research team conducted online searches for guidelines and manuals from all 50 states to review their current policies. The two main online sources for locating state manuals used in this task were:  FHWA website for MUTCDs and Traffic Control Devices Information by State (http://mutcd.fhwa.dot.gov/resources/state_info/) (accessed in October 2013).  FHWA website for State Roadway Design Manuals (http://www.fhwa.dot.gov/programadmin/statemanuals.cfm) (accessed in October 2013). Many manuals recommend selection of traffic control devices based on an engineering study/investigation or after consultation with the agency’s traffic department on an intersection- by-intersection basis, and they point to the federal or state MUTCD for guidance. In some cases the language focuses on two-way stop control (TWSC) or all-way stop control (AWSC). A few states (Minnesota, Washington, and Wisconsin) provide specific procedures or processes for intersection control selection. A few other states (Indiana and Maryland) have language in their manual that provides additional guidance on application of STOP and YIELD signs. Table 1 and Table 2 categorize states by the level of guidance on selecting traffic control devices for unsignalized intersection.

13 Table 1. Level of Guidance on Selecting Traffic Control Device for Unsignalized Intersections Available in (Online) State Manuals. States with Guidance (in Addition to or Different from MUTCD) on Selecting Traffic Control Device for Unsignalized Intersection States with Guidance on Converting Stop or Yield Control States with Intersection Control Evaluation/Analysis Procedure Florida (TWSC) Idaho Indiana Kentucky (YIELD) Maryland Montana Pennsylvania Wisconsin Indiana Maryland Minnesota Washington Wisconsin Table 2. States Not Included in Table 1. States without Online State MUTCD or Other Manual on Selecting Traffic Control Device for Unsignalized Intersection States with MUTCD Criteria Same as 2009 MUTCD States with Guidance to Use MUTCD for Traffic Control Device Selection at Unsignalized Intersection Alabama Arkansas Connecticut District of Columbia Georgia Hawaii Kansas Louisiana Mississippi Nevada New Jersey North Dakota Oklahoma Rhode Island South Dakota Vermont West Virginia Wyoming Alaska Arizona California Colorado Iowa Maine Michigan Missouri Nebraska New Mexico New York North Carolina Ohio South Carolina Tennessee Texas Virginia Arizona Colorado Delaware Florida (AWSC) Illinois Indiana Kentucky (STOP) Massachusetts Nebraska Nevada New Hampshire Ohio Oregon Tennessee Utah Virginia Washington (AWSC, local roads) State Guidance in Addition to MUTCD STOP Sign Idaho’s Traffic Manual (8) recommends use of STOP signs on minor-road approaches at intersections with arterials and other major roadways, except when a traffic signal is warranted or an engineering investigation determines other control to be safer, operationally better, and more desirable. Idaho’s Traffic Manual also recommends STOP signs at other intersections with state highways. Examples are alleys or shopping centers or high-volume (greater than

14 500 average daily traffic [ADT]) private approaches where it has been determined that the installation of such signs is in the best interest of safety and mobility on the State Highway System. The 2011 Indiana Design Manual (9) provides guidance for use of multi-way stop control in residential areas (in addition to the warrants provided in the MUTCD). Multi-way stop control is recommended at intersections of two collector streets that are primary to the area, or at intersections where there are three or more crashes in 1 year. The volume split guideline is 60–40 percent (or closer) for four-way intersections and 75–25 percent (or closer) for three-way intersections. Maryland MUTCD Section 2B.04 (Right-of-Way at Intersections) (10) has the following text in addition to the support statement in the federal MUTCD:  STOP signs should not be used to control cross traffic within medians less than 50 ft in width. Even within medians wider than 50 ft, YIELD signs should be considered rather than STOP signs.  STOP signs are not to be placed along any two adjacent intersection approaches where all traffic along that approach is not expected or required to stop unless channelizing is provided to direct certain movements away from the STOP sign.  STOP signs are not to be placed along certain intersection approaches, and omitted from other intersection approaches, when driver expectations are violated as to which approaches stop and which do not. Section 18.2.1 (STOP/YIELD Signs) of Montana’s Traffic Engineering Manual (11) provides the following guidelines, in addition to the criteria in the MUTCD, for appropriate application of STOP signs along state facilities:  Use a STOP sign on the approach of a county/city facility where it intersects the state facility.  Provide a STOP sign at the minor approach of an intersection with a private facility or service road that provides access to major traffic generators such as an office complex.  AWSC should not be used unless the traffic volume for each approach leg is approximately equal.  STOP or YIELD signs may be used at railroad/highway grade crossings that have two or more trains per day and are without an automatic traffic control device.  STOP or YIELD signs may also be used where a state facility crosses over an at-grade railroad crossing just prior to a stop/yield-controlled intersection, ensuring the availability of sufficient sight distance. Depending on the available and needed storage length, a DO NOT STOP ON TRACKS sign needs to be added. Pennsylvania’s Official Traffic Control Devices publication (12) allows inclusion of both reportable crashes and non-reportable crashes documented in the police files when checking for the MUTCD multi-way STOP sign warrant B (crashes). Additionally, the crashes considered are to be within a 12-month period during the most recent 3 years of available crash data. Pennsylvania’s guidelines also prohibit the use of multi-way stop control at intersections with

15 limited available corner sight distance unless there is no practical method of improving the sight distance or reducing the speed limit to satisfy the minimum corner sight distance values. Washington’s Design Manual (13) states that multi-way stop control is most effectively used on low-speed facilities with approximately equal volumes on all legs and total entering volumes not exceeding 1,400 vehicles during the peak hour. The text refers to the MUTCD for guidance on the application of multi-way stop control. The Florida Intersection Design Guide (14) notes that the TWSC mode requires minimal justification, and there are no numerical warrants to be applied. YIELD Sign The research team found that few state manuals had any information on the application of YIELD signs. The Indiana Design Manual (9) recommends the use of a YIELD sign at an intersection only if it is operating in a merge condition (e.g., channelized intersection with a turning roadway). Kentucky’s Traffic Operations Guidance Manual (15) recommends that YIELD signs be used to assign right of way for turning movements and not be used to assign right of way for an entire approach at any intersection. Convert STOP to YIELD Sign The Indiana Design Manual (9) references the following publications that engineers can use to select between STOP and YIELD signs:  Stop, Yield, and No Control at Intersections, Report No. FHWA/RD-81/084, FHWA, June 1981. This document provides analysis of control type, region, location (urban/rural), geometry (three-leg/four-leg), major-roadway volume, and sight distance at 140 low-volume intersections in the United States. The authors found that stop control produces the longest travel times/road-user costs, and yield control resulted in the lowest road-user costs.  NCHRP Report 320: Guidelines for Converting Stop to Yield Control at Intersections, Transportation Research Board (TRB), October 1989. This document provides a review of crash experience at 756 yield- and stop-controlled intersections in six cities. Some of these intersections were converted from stop to yield control, providing a before-after perspective. The researchers found that intersections converted from stop to yield control are likely to experience an increase in crashes, especially at higher traffic volumes. Also, four-leg intersections with yield control had a higher crash rate than T-intersections with yield control. On the other hand, because of reduced delay, lower fuel costs, and lower vehicle operating costs, it was found that yield control is more cost effective than stop control at all volume levels studied. Section 2B.06 of the Maryland MUTCD (10) provides guidance on STOP sign applications and conversion from Stop to Yield control. Table 3 lists these guidelines.

16 Table 3. Maryland MUTCD Table 2B-1a: Guidelines for Conversion from Stop to Yield Control (10). 1 Identify a stop controlled intersection candidate for change to yield control. 2 Review with the local traffic engineer and police for any known problems that might be impacted by less restrictive control. 3 Determine whether current MUTCD warrants for stop control are met by current traffic conditions. 4 Review accident data for the past three years. Intersections should not be considered for STOP to YIELD sign conversion unless there have been two or less reported accidents in a year, or four or less in three years. 5 Based on the ADT’s (or estimated volume ranges) for both the major and minor approaches, determine the relative priority of conversion, as follows: a. Major roadway volume (ADT) of less than 2,000 and minor roadway volume of less than 200 indicates a high priority for probable conversion. Field confirmation of good sight distance shall be obtained. b. If either the major ADT is between 2,000 and 3,000 or the minor ADT is between 200 and 500, the priority drops to medium. A field study to confirm good sight distance shall be obtained; a short peak period turning movement count shall be obtained to determine that volumes have not increased substantially, and confirm that no problems such as abnormal amounts of forced stops or conflicts with major street traffic exists. c. Greater volumes up to 10,000 major and 1,000 minor indicate a low priority and consideration shall proceed only after a more detailed study of volumes, conflicts and driver behaviors to determine if the safety risk from proposed conversion is acceptable. 6 Field check to measure the sight distance at the intersection approach where the stop control is being considered for change to yield control. Ascertain that the measured sight distance complies with sight distance standards that are consistent with the latest edition of AASHTO’s “A Policy on the Geometric Design of Highways and Streets.” 7 After following the procedure outlined above and concluding that traffic demand can be accommodated safely and more effectively, stop control may be changed to yield control. Intersection Control Evaluation Processes Minnesota The Minnesota Department of Transportation’s (MnDOT’s) Office of Traffic, Safety, and Operations provides guidelines on intersection control evaluation (ICE) for intersections on trunk highways. MnDOT does not require an ICE report for intersections that are determined to need minimal traffic control (two-way stop or no control), but requires it for any other type of control (all-way stop, roundabout, traffic signal, median treatment to reduce traffic movements, or other advanced traffic control systems such as continuous flow intersections). Also, if the ADT for the minor leg or the intersection is less than 1,000 ADT, an ICE is not required. The guidelines recommend evaluation of the four-way stop if the combined ADT is between 7,500 and 50,000. Table 4 is the guide provided in the Intersection Control Evaluation report (16) for determining which intersection options should be evaluated based upon combined ADT volumes. For intersections with volumes close to the range boundaries in the table, it is recommended that options given for both ranges be evaluated. Figure 1 shows a flowchart summarizing the ICE process. For analysis of multi-way stop control, the Minnesota MUTCD warrants (same as those in the federal MUTCD) are to be considered.

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18  Existing condition: Current physical characteristics (e.g., speed and sight distance) and collision history are to be reviewed to identify any problematic movements.  Delay analysis: The delay analysis focuses on determining the peak-hour level of service (LOS) of an individual intersection. When the through roadway daily traffic is 3,500 or less, delay analysis is not required except in cases where the higher-volume roadway is controlled or where channelization is proposed. For AWSC, guidance provided in the MUTCD is to be followed.  Operational considerations: An operational analysis is a more encompassing review of the ability of the intersection to provide sufficient capacity in the network, and includes consideration of the environment that users will encounter at all hours of the day. In an operational analysis, the effect of the type of intersection control on the surrounding network is to be reviewed.  Benefit/cost analysis: The only societal costs/benefits the Washington State Department of Transportation evaluates are those due to collisions and delay. Project costs include cost of design, right of way, construction, and annual maintenance.  Bicycle/pedestrian facilities: The need for pedestrian/bicycle facilities is to be reviewed, along with required Americans with Disabilities Act accommodations.  Context-sensitive/sustainable design: The intersection should be reviewed not only for its physical aspects as a facility serving specific transportation objectives, but also for its effects on the aesthetic, social, economic, and environmental values, needs, constraints, and opportunities in a larger community setting. Wisconsin Wisconsin’s Facilities Development Manual (17) provides guidance on the selection of intersection control through the ICE process for intersections on state trunk highways. The ICE process is conducted in two distinct phases: scoping and alternative selection. In the scoping phase, a memorandum that recommends traffic control alternatives for further evaluation in the next phase is prepared. As part of this phase, a review of crash diagrams, signal warrants, all-way stop warrants, operations (using the 2010 Highway Capacity Manual), and alternative feasibility (e.g., potential environmental impacts and right-of-way impacts) is conducted. In the alternative selection phase, a more detailed evaluation of the alternatives is documented in the ICE worksheet to assist the region in selecting the type of traffic control, lane configuration, and intersection type for the studied intersection. In the alternative selection phase, factors considered include safety, operational analysis, right-of-way impacts, costs, practical feasibility, pedestrians and bicycle users, oversize-overweight freight network, and environmental impacts. AWSC warrants are discussed in Wisconsin’s Traffic Guidelines Manual (18) within Section 13-26-5. This review includes all of the criteria in MUTCD Section 2B.07, both guidance and optional, and the following supplemental criteria:  Functional highway classification: For desirable AWSC, the intersecting roadways should have the same or similar functional class (i.e., different by only one level) on at least three approaches.  ADT: For AWSC, it is highly desirable for the intersecting roadways to have closely balanced ADTs on at least three approaches, i.e., the volume of at least one of the minor

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20 OUTREACH TO PRACTITIONERS While some potential methodologies have been documented through large-scale research studies and distributed through national publications, other methodologies may be under consideration and/or experimentation in more localized applications. To try to identify these guidelines, the research team used the following posting on the ITE Online Community on October 23, 2013: Dear Colleagues, NCHRP Project 3-109 is evaluating criteria for selecting the type of control at unsignalized intersections. These criteria will be considered for inclusion in the MUTCD. The reason for this investigation is that the current MUTCD guidelines date back to 1971. As part of this process, we are looking for novel approaches for selecting traffic control at unsignalized intersections used by state and local agencies. Please email your agencies’ approach to selecting traffic control at unsignalized intersections to me or respond to this forum post. Responses regarding STOP and YIELD signs were received from six individuals. Three respondents provided documents from MnDOT, including the fall 2007 Intersection Control Evaluation report (16) and the 2007 Intersection Control Evaluation (20) draft document. These documents provide a process that identifies the best intersection control through a comprehensive analysis. One of these respondents also included a sample report. Two of the respondents were from Wisconsin. One of the respondents shared Wisconsin’s Traffic Guidelines Manual (18) section on STOP signs. This document is discussed in the “Intersection Control Evaluation Processes” section. The other Wisconsin respondent shared the City of Janesville, Wisconsin, criteria (21); see Table 5. The criteria provide the following support for their STOP and YIELD sign procedures: STOP Sign Procedure As is documented in the report, our recommendations are influenced by the fact that a consistent, predictable pattern of arterial streets (STOP signs) results in an overall safer system than having control at all intersections. We, therefore, first look at whether a requested STOP sign location fits into that system. Minimum traffic volumes, as outlined in the criteria of 2,000 vehicles per day entering the intersection, are generally required before consideration of installation of an isolated STOP sign that is not part of the overall arterial street system. General YIELD Sign Procedure YIELD signs are most useful at intersections which are isolated and are not part of the arterial street system where entering volumes are greater than 1,000 vehicles per day. In many YIELD sign requests, the concern is blocked vision. In such cases, our first response is to look at the intersection, determine if a vision blockage is in violation of the City’s vision triangle ordinance. If so, we administratively enforce the ordinance which usually requires trimming of bushes or trees which may in turn eliminate the need for the traffic control sign. In other cases where the isolated volumes are higher than 1,000 vehicles per day and/or

21 where vision problems are not able to be so easily corrected, a YIELD sign is appropriate. A representative of Portland noted that he uses NCHRP Report 562 (22) to guide decisions on how to enhance pedestrian/bike crossings. Table 5. City of Janesville, Wisconsin, Criteria (21) for Installation of Traffic Control Devices, Dated August 1977. Criteria Yield Control Stop Control Multiway Stop Control Signals a 1. Arterial Street N/A Yes Both Both 2. Entering Volume (Minimum) 1,000 vpdb 2,000 vpd 4,000 vpd Major 65% of Total Major street 400 vphc for any 8 hr, both legs; minor street 120 vph for same 8 hr, either leg. 3. Preventable Crashes (Last 12 Months) 3 3 5 5 NOTE: If crashes exceed these figures, volume requirements can be reduced by 25% 4. Safe Approach Speed >10 mph (by Vision) <10 mph (by Vision) N/A N/A 5. Interruption of Continuous Flow N/A N/A N/A Major street 750 vph for any 8 hr, both legs; minor street 75 vph for same 8 hr, either leg. 6. Progressive Movement N/A N/A N/A Major street 300 vph for any 8 hr, both legs; minor street 120 vph for same 8 hr, one leg. 7. School Crossing Volume N/A N/A N/A 100 grade school children for each of 2 hr; 400 vph for same 2 hr. 8. Pedestrian Volume (Minimum) N/A N/A N/A 150 pedestrians for each of 4 hr/day, 400 vph for same 4 hr. 9. Turning Movements N/A N/A N/A N/A 10. Actual Approach Speed N/A N/A N/A N/A Minimum Number of Criteria to Be Met One of the Above One of the Above All of the Above #1 and One Other a Signal criteria now follow state/federal guidelines (as of 1996). b vpd = vehicles per day c vph = vehicles per hour