- Statewide Raised Median Toolkit

RAISED MEDIAN ASSESSMENT TOOL

Purpose

The purpose of the Assessment Tool is to guide decision-makers to determine the appropriateness and potential benefits of raised medians on specific roadway corridors. Potential users of this tool include planners, design engineers, traffic engineers, and project managers.

Limitations

The Assessment Tool is not designed to be a strict mandate on whether or not raised medians should be installed. Instead, the tool provides information and guidelines to direct the user in making the best decision for a specific location. Key roadway criteria are combined with other considerations to provide a more complete picture of the facts, resulting in educated, defensible decisions.

Step 1: Key Roadway Criteria

1. What is the projected annual average daily traffic in the design year? required

2. How many total travel lanes will there be after the project is constructed? (Do not count turn lanes or center median lanes.) required

Step 2: Secondary Criteria

3. What is the setting of the project? optional

4. Looking at the crash history for the last 3 years on this corridor (within the project limits), what is the percentage of left turn (angle) crashes as compared to total crashes? optional

5. How many full-accesses are there on this corridor per mile? optional

To determine access density, look at the corridor on an aerial photograph and count the number of full-access driveways and cross-streets within the project limits. Count both sides of the street, so a cross-street would count as two accesses. Then divide this number by the length of the project in miles.

For example, if this corridor is 0.5 miles long and has 28 accesses, the access density is 28 / 0.5 = 56 accesses per mile.

Step 3: Other Considerations

ROADWAY GEOMETRY

Do you have the ability to provide U-turn opportunities at mid-block locations? optional

Have you considered opportunities to consolidate driveways and negotiate cross-access agreements with property owners? optional

PEDESTRIAN, BICYCLE AND TRANSIT ACTIVITY

Is this corridor either a designated bike route now or planned to be one in the future? optional

Will there be a buffer area or on-street parking between the sidewalk and roadway? optional

Are there currently mid-block pedestrian crossings on this corridor? optional

Will a median result in out-of-direction travel for transit vehicles? optional

LAND USE TYPES

Are there businesses that primarily draw customers from pass-by traffic (such as car washes, fast food restaurants, and gas stations) where access will be affected? optional

NEIGHBORHOOD CIRCULATION

Will a raised median cause traffic volume to increase on local streets due to re-routing of left-turning traffic? optional

ADJACENT PARCEL ACCESS OPTIONS

Review the adjacent parcels along the corridor in light of their current zoning and future land use as designated in approved city/county plans. Will all parcels have adequate access as determined by local ordinances? optional

COMMUNITY AESTHETICS

Are aesthetics an important consideration for the corridor? optional

EMERGENCY SERVICE ACCESS

Have emergency service providers identified concerns? optional

PUBLIC INPUT

Has the public input been positive? optional

Key Roadway Criteria

What is the projected annual average daily traffic in the design year?

How many total travel lanes will there be after the project is constructed?

Secondary Criteria

What is the setting for the project?

Looking at the crash history for the last 3 years on this corridor (within the project limits), what is the percentage of left turn (angle) crashes as compared to total crashes?

How many full-accesses are there on this corridor per mile?

Are raised medians appropriate for your corridor?

While no tool can tell you for certain that a raised median should definitely be constructed or not be constructed, if multiple categories in this assessment indicate Moderate or High Benefit, a raised median should reduce crashes, reduce travel times and provide better corridor operations.

Alternatively, if multiple categories indicate Low Benefit, raised medians may not be the best answer for your corridor. In this case, you may want to install raised medians for aesthetic or traffic calming reasons, but they will not provide a significant traffic operations or safety benefit.

Proceed to Step 3 to discover other things you should consider as you make your decision. Considerations such as pedestrian, bicycle, and transit activity; land use; neighborhood traffic circulation; emergency services access; and public input are just as important as the traffic operations and safety factors. The Engagement Guide can also help guide you when meeting with property owners and other stakeholders to refine your plan.