By Julia Warren, City of Lake Oswego
Crime Prevention Through Environmental Design (CPTED) is a concept applied by combining both design and crime prevention strategies.
It has been found that design tools such as lighting, fencing, foliage, and even color can be facilitated to welcome “intended users”. Proper use of these design tools may allow increased “natural surveillance” while establishing clear access points and boundaries, reducing the opportunity and occurrence of crime. When this occurs, a sense of ownership and the feeling of a safe community is enhanced.
“Unintended users” are those who may use the space to commit crimes or who exhibit other behaviors unwelcome to “intended users”. “Intended users” are residents, customers, or citizens using the area for non-criminal purpose. CPTED applies the theory that when the amount of “intended users” increases, the amount of “unintended users” decreases.
Imagine a neighborhood that is having problems with “unintended users” using an alley that runs behind several neighborhood houses. Residents have expressed that they do not feel safe using the alley or going into their back yards at night. The alley has been overrun with litter, graffiti, and drug paraphernalia. Several of the neighbors have put up chain-linked fencing with barbed wire along the top to prevent the possibility of “unintended users” entering their property.
Using CPTED strategies, the neighborhood may solve the problems in the alley with a few minor changes.
Lighting is a great start because criminals do not like to be noticed or seen. Lighting that easily identifies anyone will discourage “unintended users” from using the area. CPTED takes into account lighting and fixtures that allow for low light pollution, good color rendition, and smooth transition between one light source to the next. Good lighting not only causes “unintended users” to feel exposed, it allows for great identification for witnesses and mechanical surveillance.
Selecting a good fence is also encouraged. While chain-linked fencing provides “access control”, it can often give “intended users” a feeling that the area is not safe. Because it is good to have “intended users” use an area, they should perceive it as safe. An option is to use fencing that allows for “natural surveillance” while presenting a less threatening appearance, such as decorative wrought iron.
“Natural Surveillance” is a term used to describe how well people can see an area without obstruction. If an “unintended user” senses they can be easily seen, they are less likely to use an area for criminal purpose.
Opening up back yards to the alley can increase a sense of ownership for residents and allow them to socialize and get to know their neighbors. When neighbors know each other, they are more likely to recognize people who do not belong.
It is also important that the appearance of the alley be maintained and exhibit a well cared for appearance. Review the two images and decide which alley you would feel comfortable entering.
An “intended user” would be more likely to feel safe in the alley presented in Figure 1. A criminal or “unintended user” would be more likely to use the alley presented in Figure 2.
In Figure 1, notice the well-groomed foliage. The plants and fencing are used to create “symbolic barriers” between private and public space while allowing “natural surveillance”. The windows of the houses have a clear view of the alley. In addition, having the garages face the alley insures that residents will be driving through the alley, further increasing surveillance.
Because the alley in Figure 1 is well maintained with high visibility, it is unlikely that “unintended users” would enter this alley with criminal intent.
The alley example is only one of many. CPTED has been used to convert everything from bus stops to entire communities, accomplishing it’s goal to reduce the occurrence and fear of crime while improving the quality of life.