Greenways are corridors of protected open space managed for conservation and recreation purposes. Greenways often follow natural land or water features and link nature reserves, parks, cultural features and historic sites with each other and with populated areas. Greenways can be publicly or privately owned and some are the result of public/private partnerships. Trails are paths used for walking, bicycling, horseback riding or other forms of recreation or transportation. Some greenways include trails, while others do not. Trails and greenways positively impact individuals and improve communities by providing not only recreation and transportation opportunities, but also by influencing economic and community development.
Greenways are “a linear open space established along either a natural corridor, such as a riverfront, stream valley or ridgeline or overland along a railroad right-of-way converted to recreational use, a canal, a scenic road or other route”. Greenways should be thought of as corridors. Some greenways serve as conservation corridors for plants and animals and do not permit human use. Land based greenway systems are normally composed of trails that traverse a variety of terrestrial based landscapes. Water based greenway systems use streams, rivers, lakes and larger bodies of navigable water, including inland seas. Some of the many trails and greenways benefits include,
- Making communities better places to live by preserving and creating open spaces
- Encouraging physical fitness and healthy lifestyles
- Creating new opportunities for outdoor recreation and non-motorized transportation
- Strengthening local economies
- Protecting the environment
- Preserving culturally and historically valuable areas
Types of Greenways
Greenway and trail systems vary in size, scope and function. They can include:
1. Local systems within a neighbourhood
2. Communitywide systems
3. Regional systems covering multiple counties
4. State-wide, multistate and national systems
Greenway systems also vary by location. They can include urban, suburban, rural, regional and state greenways. Greenways and trails have become two of the most popular products of the outdoor conservation movement, largely because they meet the needs of different constituent groups. Successful greenways and trails offer a wide range of benefits, including recreation, health and wellness, transportation, economic and education.
Planning and Design Elements
Several factors go into the development of functional and successful greenways systems.
1) Accommodating the User
Most greenways should serve the interests of a wide range of users, including people who want to walk, bike or view wildlife. Some greenways will be developed to serve conservation needs,
including habitat, floodplain or water quality protection. Greenways with trails should be designed and constructed to be accessible to all persons, regardless of their abilities.
2) Connectivity
The most successful greenways link people to popular destinations. Each segment of a system should have logical and functional endpoints. Greenways with trails that serve as links throughout a community are the most popular for users. Sometimes greenways will end abruptly, especially in urban areas. Greenways should be linked to other trails, conservation areas, parks and to an on-road network of bicycle facilities and sidewalks. Connectivity is especially important for plants and animals. In this manner, greenways serve as “gene-ways,” offering the opportunity for migration. Gene-ways are becoming important to the survival of plant and animal species worldwide due to fluctuations in temperature, rainfall and food source.
3) Multiuser Conflict
Multiuser conflict is regarded as the most serious safety concern for greenways and trails. Conflicts between cyclists and pedestrians are the most prevalent and are usually caused by reckless and unsafe behaviour, incompatible use values or by overcrowding. The most effective remedies begin with design and management. Trails should be designed to reduce conflict by widening the trail tread or by separating the trail tread for different users. The “tread” is the surface area used by trail users. Single tread, multiuse trails can also be managed to reduce conflicts, sometimes by separating users under a time-of-use or zoning policy. Involving user groups in the design of a trail is the best way to both understand local needs and resolve the potential for multiuse conflict. It is also important to post trails with a trail use ordinance and provide educational materials on how to use the trail.
4) Fitting Greenways to the Environment
The most enjoyable greenways celebrate the natural landscapes and native environments in which they traverse. Greenways should have rhythm and syncopation and flow within their surroundings so that they captivate users. Greenways should follow the natural contours of the land and take advantage of native landscape features such as water, groupings of vegetation, scenic views and interesting built features.
5) Integrating Greenways into the Built Environment
Greenways should also celebrate the built landscapes they traverse. Planners and designers often try to hide views deemed unpleasant. This may not always be a good idea. For greenways designed to be used by people, it is much better to keep view sheds open. Trails through urban landscapes provide an opportunity to interpret the surrounding environment. Great care must also be taken to successfully fit a new greenway and trail into the urban fabric. For example, the conversion of abandoned railroad corridors has been a growing resource for new urban trails in the past 20 years. But this practice presents challenges for different type of transportation activity. Creating new intersections between roads and converted rail-trails is the greatest challenge for these urban trails. It is important that intersections be designed to clearly determine who has the right-of-way. Intersections should also be very clearly marked for all groups to delineate crossing zones for trail users. Pavement markings, signage, lighting and texture pavement can all be used to make intersections safer.
Greenway Width
Greenways will vary in width depending on the amount of land available to support their intended use. Trail-based greenways may be quite narrow, with the sole purpose to support a hiking or biking trail. For metro or urban systems, urban trail greenway corridors should range in minimum width from 50 to 100 feet (15.2 to 30.5 meters). When urban greenway widths are less than 50 feet (15.2 meters), problems will occur with separation from adjacent land uses, maintenance and operations and enjoyment of use. For suburban greenways and rural greenways where other functions are to be included, such as storm water management, flood abatement, wildlife preservation or historic interpretation, minimum widths should begin at 100 feet (30.5 meters) and may extend beyond 300 feet (91.4 meters).
The width for a specific greenway project can and should vary according to the different requirements encountered. In some areas, extra land may need to be protected to support ecosystem preservation; in other areas of the project, a minimum width may be desirable to support through-passage of trail users.
Trail Width
For multiuse trails within a greenway, the American Association of State Highway Transportation Officials (AASHTO) recommends a minimum width of 10 feet (3 meters). This width, required for projects that use federal transportation funds, is necessary to accommodate two-way bicycle and pedestrian traffic on the prepared trail tread. To accommodate heavy traffic in urban areas, it may be necessary to increase the width to 12, 14 or even 20 feet (3.7, 4.3, or 6.1 meters). In some cases, it may be desirable to divide the trail into “wheeled” and “non-wheeled” treads if the right-of-way and landscape can support separate treads.
Wheeled trails support users who bicycle or use other mechanical, human-powered means, including rollerblades to navigate a trail. Wheeled trail treads should be 10 feet (3 meters) wide. Non-wheeled users are pedestrians, and normally include people with disabilities who use a wheelchair to navigate a trail. Non-wheeled trail treads can be 6 or 8 feet (1.8 or 2.4 meters) in width. For greenways not funded by transportation dollars, and that do not intend to accommodate multiple user groups, it may be possible to develop a trail tread that is 6 or 8 feet (1.8 or 2.4 meters) wide. Generally, this is done for single-user groups, such as pedestrians or equestrians. Even in these cases, maintenance and public safety accommodations may require a wider tread.
Public Involvement in Greenway and Trail Design
Incorporating public input into the design of a greenway and trail system or segment, is an important consideration. The manner in which public input is received and used will go a long way toward gaining acceptance and buy in for the project. Finding the most appropriate method for involving the public in the process is important. There are different ways to involve the public, including meeting with individual landowners, forming citizen’s advisory committees, hosting public workshops and conducting a public survey.
Regardless of which techniques are used, all public input should be recorded and made part of a permanent record of the greenway or trail project. Greenways often traverse landscapes that have historically been regarded as the back door or backyard for residential, commercial, office and retail lands. Having a public right-of-way in front of and behind a home or business often raises safety and security concerns for property owners. The best strategy to address these concerns is to collect and disseminate factual information about the greenway project. It may be necessary to provide examples of where successful projects have been developed in nearby communities or neighbourhoods. When facing opposition, it is important to emphasize that masses of greenways and trails have been successfully open to public use over the past 20 years.
Project Development
The actual development of a greenway or trail project depends on the availability of land and money. Adequate right-of-way is required to support the multiple purposes of a greenway. Appropriate land is also required to support the intended trail experience. One of the greatest shortcomings in greenway and trail planning is the inability of local communities to conserve and protect adequate land for a greenway or trail project. Some land corridors are too narrow to achieve intended results.
Factors that affect project costs include grading of terrain, drainage and subsurface construction. These costs can be lowered through the use of volunteer labour, donation of materials and below market services from local contractors and manufacturers. They can also help reduce maintenance costs. Some of the most important issues to address and resolve in developing a greenway or trail include the following.
- Adequate drainage of water away from the trail surface
- Public access points, spaced no more than one quarter mile (0.4 kilometers) apart
- Signage systems
- Appropriate inspection of greenway and trail landscapes to correct deficiencies
- Treatment of intersections with roadways and utilities
- Maintenance and public safety
Emerging Issues
Greenway and trail development has adapted to concerns over adequate recreation, an interconnected transportation network and the protection of floodplains. Currently, the dominant concerns include health and wellness and water quality.
a) Health and Wellness
An active community is a healthy community. Numerous studies affirm that sedentary lives and prolonged periods of inactivity are major deterrents to healthfulness. Communities can help combat sedentary lifestyles by developing and providing better access to landscapes that encourage people to venture outside and enjoy the outdoors, which includes greenways and trails. When these landscapes are incorporated as a system within the fabric of development, they become even more valuable to health and wellness pursuits. The result is an interconnected environment that supports a range of outdoor activities and encourages community residents to incorporate physical activity and exercise into their daily lives.
b) Water Quality
Greenways can serve as filter strips for overland runoff, trapping harmful pollutants before they enter creeks, streams, rivers and lakes. The key is to establish a system of greenways that mirrors the native hydrology of a local landscape. When these greenways are properly sized, they can be very effective in protecting source waters from degradation and may also be used to clean and restore degraded waters.
Complexity of Greenways
Greenway development is often a reflection of community values and the commitment to balancing conservation and land use development. Greenway and trail development is a complex undertaking. It requires understanding the opportunities and constraints of the natural and human made environments and accounting for the interests and needs of diverse user groups. Defining a logical process for planning and designing each and every greenway and trail system or segment, is one way to ensure that all factors influencing development have been appropriately addressed and resolved.
