Fighting crime through environmental design

By BILL SCHMIDT
Guest columnist

While safety by design has long been practiced through building code requirements and local ordinances, the impact of its use to prevent crime in public spaces is a relatively new concept. In urban environments, Crime Prevention Through Environmental Design (CPTED) combines urban design strategies and architectural elements to optimize safety in outdoor spaces.

This approach is based on four basic principles:

Natural surveillance

Designing spaces that maximize visibility allows for constant observation of behavior. A well-documented example of natural monitoring in practice is the effects of tree canopy in cities.

While it may seem counterintuitive, areas with more trees have been shown to encourage people to spend time outdoors, creating easier observation areas than environments that require indoor gatherings. A study conducted by environmental researchers at the University of Illinois found that areas surrounded by lush vegetation had 48 percent fewer property crimes and 56 percent fewer violent crimes.

Territorial reinforcement

Territorial reinforcement in landscape architecture uses hardscape elements or natural barriers to define public and private areas. In simpler terms, design elements are used strategically to draw a line between “my space” and “your space.” Features such as shrub barrier plantings that separate a local park from a family residence deter users from trespassing on private property or engaging in illegal activities. Other common examples of these design elements include fences, bollards, water features and retaining walls.

Natural access control

Natural design elements are used as tools to subtly guide users without physically restricting their access to a space. An example of this is signage that is often found along hiking trails. The designation of approved public rights-of-way not only provides a sense of direction in the area, but also promotes the intended pedestrian flow. This limits the opportunities for crime as perpetrators develop a sense of risk when they move away.

maintenance

Regular maintenance of outdoor areas shows that a space is cared for and allows for its intended use, thereby preventing criminal activity. An unkempt space could prevent design elements from achieving their desired CPTED effect and be a sign of lack of concern for the environment. For example, overgrown bushes obscure users' views and make natural surveillance difficult. Inconsistent maintenance of an area can even signal to potential criminals that there is a higher tolerance for chaos, making the area a prime target for unwanted behavior.

By thoughtfully combining creativity and functionality, landscape architects have the opportunity to create urban havens where crime declines and communities thrive.

Bill Schmidt, PLA, ASLA, LEED AP, is director of landscape architecture at Weihe Engineers, Inc.