Connectivity
Paved paths connect cul-de-sacs in this community.
A child who lives a stones throw from a school must be driven or bused if there is not a connection between home and the school.
The connectivity of various bicycle and pedestrian facilities directly impacts the ability to walk or bicycle to school. Characteristics of a well-connected road or path network include short block lengths, numerous three and four-way intersections and minimal dead-ends (cul-de-sacs).[27] As connectivity increases, travel distance decreases and route options increase. A network of streets, sidewalks, bicycle lanes and paths in which all parts are well-connected to each other reduces the distance children have to travel to get from home to school, allows for the use of more local streets rather than major roadways and provides a greater choice of routes to travel to and from school.
Street layout directly impacts the ability to walk or bicycle to school. Frequently, the layout of subdivision streets makes distances much longer than they need to be. Long neighborhood block lengths and cul-de-sacs contribute to this problem. Neighborhoods that are designed with long blocks and numerous cul-de-sacs are often barriers to walking and bicycling to school; they reduce connectivity and increase travel distance between the home and school.
The diagram on the left illustrates a street layout based on a grid system, and the diagram on the right illustrates a layout which consists of many dead end streets with few exits or entrances. The diagram on the left provides a greater street connectivity than the diagram on the right. A trip from home to school for a child who lives in the neighborhood on the left is feasible on foot or by bicycle. It features a short distance using local streets with no major streets to navigate. For the child who lives in the neighborhood on the right, the trip is longer and takes place mostly on busy streets. As a result, many parents will choose to drive their child to school, which will overburden the arterial street system and create unnecessary traffic congestion at the school.
To help solve the cul-de-sac issue, connector paths between cul-de-sacs and other destinations can be constructed in one of three ways including:
- At the time when the subdivision is first developed.
- As a voluntary retrofit.
- As a mandatory retrofit when the property is sold or redeveloped.
Connectivity is an important consideration when making a community walkable.
Another potential solution is to create zoning ordinances that prohibit or limit the number of cul-de-sacs in a defined area or subdivision. Once constructed, attempts to retrofit existing cul-de-sacs with connectors often require significant efforts to garner support from neighbors and elected officials. Zoning ordinances can also be used to establish a maximum block length.
School connectors can be built on dedicated public rights-of-way or on sidewalk easements. Children will frequently find their own informal ways of walking or bicycling to school. Instead of discouraging these paths, pay attention to the children and formalize the connections they make. Not all routes to school need to be paved, but paved routes will provide for an all-weather connection that can be used on rainy days by pedestrians or bicyclists.
Treatment: Increasing Connectivity
Description/Purpose
Increasing connectivity of streets, paths and sidewalks reduces travel distances and makes it easier for pedestrians and bicyclists to access destinations.
Expected Effectiveness
The presence of paths, bridges or other neighborhood connectors can increase the number of walking and bicycling trips and decrease the time and distance it takes to travel from one point to another.
Costs
Costs vary by project conditions and scope; no additional costs are associated when connectivity is included in initial construction.
Keys to Success
- Sidewalk and roadway connectivity should be considered at the outset of design.
- Developments can be retrofitted for connectivity with the use of cut-throughs.
Key Factors to Consider
- Increasing roadway connectivity may sometimes cause an increase in unwanted through-vehicle traffic. Appropriate studies should be performed to estimate the effects of increasing roadway connectivity.
- It may be possible to retrofit existing, poorly connected street networks with a pedestrian path, bridge or sidewalk to increase connectivity.
Evaluation Measures
- Pedestrian and bicycle volume.
Putting It Into Practice: Connector Paths
Mary Scroggs Elementary School, Chapel Hill, NC
The path between the two houses in the cul-de-sac creates a connection to the local school.
One of the main barriers to walking and bicycling to school is distance. A child who lives a short distance from a school may need to be bused or driven if there is not a reasonable connection between home and the school. Disconnected subdivision street layout often makes distances between origins and destinations much longer than the straight line distance between the two locations. By not connecting to another street, cul-de-sacs contribute to the problem.
As part of a new subdivision in Chapel Hill, NC a connector path was built to connect Mary Scroggs Elementary School to a cul-de-sac of an adjacent residential street. Sixty percent of students at Mary Scroggs Elementary School now walk or bicycle to school.