Appendix Three: State of Iowa Bicycle and Pedestrian Accommodation Guidance

IOWA DEPARTMENT OF TRANSPORTATION
BICYCLE AND PEDESTRIAN ACCOMMODATION GUIDANCE

ADOPTED BY THE IOWA TRANSPORTATION COMMISSION

May 11, 1999

BICYCLE AND PEDESTRIAN ACCOMMODATION GUIDANCE

Iowa’s roadways serve several modes of transportation including trucks, automobiles, buses, motorcycles, bicycles, and pedestrians. Bicyclists carry the same rights and responsibilities, as motor vehicle drivers are currently legal on virtually all public roadways in Iowa.

It is federal transportation policy to "promote increased use of bicycling, and encourage planners and engineers to accommodate bicycle and pedestrian needs in designing transportation facilities for urban and suburban areas." The Iowa Department of Transportation will consider the needs of all transportation users and also encourage metropolitan and regional planning agencies to plan for bicycle and pedestrian accommodations in their areas.

Bicycle Accommodation Guidance

The department’s policy is to provide safe, convenient and adequate bicycle facilities along the state highway system. As part of the development of every highway construction project, the department will consider the following situations to determine whether further bicycle accommodation is needed within the highway corridor.

When highways in and around rural communities are the primary means of bicycle transportation due to the limited availability of other facilities.
When the highway provides primary access to a park, recreational area or other significant destination.
When the highway provides unique access across a natural or man-made barrier, i.e., bridges over the rivers or roads or over/under access-controlled facilities and roadways.
The highway provides a connection in an otherwise continuous bicycle facility.
When the highway project negatively affects the recreational or transportation utility of an independent bikeway or trail. Highway projects will negatively affect at-grade paths and trails when they are severed, when the projected roadway traffic volumes increase to a level that prohibits safe crossings at-grade, or when the widening of the roadway prohibits sufficient time for safe crossings.

The department will also provide further bicycle accommodation within the highway corridor if a Regional Planning Affiliation (RPA) or Metropolitan Planning Organization (MPO) can provide a forecast of the bicycle traffic five years after project completion that shows the volume of two-way bicycle traffic averages at least 25 bicycles per day during the peak three months of the bicycling season and motor vehicle traffic on the highway or street exceeds 1,000 vehicles per day. The forecast of bicycle and motor vehicle traffic will be reviewed and approved by the department. In addition to the forecast, the RPA or MPO will show through an analysis of alternatives, that the best alternative is accommodation within the state highway corridor. The department will provide a methodology to the RPAs and MPOs to follow when developing the travel forecasts and when evaluating alternatives.

Design Guidance

The department will utilize the AASHTO Guide for the Development of Bicycle Facilities as the basis for design guidance. Further guidance is provided in FHWA’s Selecting Roadway Design Treatments to Accommodate Bicycles.

The location of the bicycle accommodation may be on the highway (e.g. bike lanes, paved shoulders, etc.) or off the highway as a separated bicycle path. In most cases, the preferred location of bicycle accommodation is on the highway. The AASHTO Guide for the Development of Bicycle Facilities lists several reasons bicycle accommodations are preferred on the highway:

At intersections, motorists entering or crossing the highway often will not notice bicyclists on separated bicycle paths approaching from their right, as they are not expecting contra-flow vehicles. Motorists turning to exit the highway may likewise fail to notice the bicyclist. Even bicycles coming from the left often go unnoticed, especially when sight distances are limited.
Signs posted for roadway users are backwards from contra-flow bike traffic on separated bicycle paths, and therefore these cyclists are unable to read to read the information without stopping and turning around.
Many bicyclists will use the highway instead of the separated bicycle path because they have found the highway to be more convenient, better maintained, or feel safer riding on the road.
Although the separated bicycle path should be given the same priority through intersections as the parallel highway, motorists falsely expect bicyclists to stop or yield at all cross-streets and driveways. Efforts to require or encourage bicyclists to yield or stop at each cross street and driveway are inappropriate and frequently ignored by bicyclists.
Stopped cross-street motor vehicle traffic or vehicles exiting side streets or driveways may block the separated bicycle path crossing.

In some cases, a separated bicycle path may be appropriate due to the factors such as traffic volume, type of motor vehicles, traffic speed, and skill level of users.

Types of Bicycle Improvements/Design Treatments

There are several ways in which roadways can be constructed to enhance bicycle transportation. Adding or improving shoulders can often be a feasible way to accommodate bicycles in rural areas. Bicycle lanes and wide curb lanes are the primary improvements for urban areas, where available road space is a concern. The following design treatments are extensively explained in the AASHTO Guide for the Development of Bicycle Facilities.

Shoulders: A paved portion of the roadway to the right of the edge stripe. AASHTO recommends paved shoulders specifically for bicycle accommodation improvements in rural areas. Shoulders will be paved in accordance with design standards and paved shoulder studies. Bicycle traffic on a paved shoulder will typically be one-directional with the flow of traffic; therefore both shoulders will be paved when providing accommodation for bicyclists.
Wide Curb Lanes: An outside travel lane on highway sections with a width of greater than 12 feet (14 feet typically). Used primarily in urban areas, the wide curb lanes can allow road use by both bicyclists and motorists without conflict.
Bicycle Lane: A portion of the roadway, which has been designated by striping, signing and pavement markings for the preferential or exclusive use of bicyclists. Bicycle lanes should always be one-way facilities carrying traffic in the same direction as adjacent motor vehicle traffic, and they should not be placed between parking spaces and the curb. Bicycle lanes offer a channelizing effect on motor vehicles and bicycles.
Separated Bicycle Path: A bikeway physically separated from motorized vehicular traffic by an open space or barrier, and either within the highway right-of-way or within an independent right-of-way.

Incidental design factors that improve the safety of bicycle travel will be considered on all state highway improvements. These include, but are not limited to:

Drainage grates and utility covers suitable for bicycle travel
At-grade railroad crossings that accommodate bicycle movements

Implementation

Consideration of bicycle accommodation will occur at all stages of planning and project development. When feasible, the recommended design treatments will be implemented as part of new construction, reconstruction, or preservation of the roadway.

Accommodations requiring grading and/or the purchase of right-of-way will normally not be considered as part of a highway preservation improvement. Consideration of bicycle accommodation will not occur as part of highway maintenance activities. When accommodation is provided as part of a highway improvement project, the cost for the facility will be considered an additional highway construction cost.

Providing bicycle accommodation independent of a highway construction project will be considered with construction funding obtained from local jurisdictions or other federal and non-road use tax state sources.

Maintenance

The department will be responsible for the ongoing maintenance of bicycle facilities within the state highway right-of-way.
The department will not be responsible for maintenance of bicycle facilities within the state highway right-of-way.

Pedestrian Accommodation Guidance

The department will consider the impacts to pedestrian accommodation at all stages of the project development process and encourage pedestrian accommodation efforts when impacted by highway improvements. Cost of these accommodations made at the time of the highway improvement will be considered additional roadway construction costs. Providing pedestrian accommodation independent of a highway construction project will be considered with construction funding obtained from local jurisdictions or other federal and non-road use tax state sources.

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