Transform Baltimore Health Impact Assessment

Authors: Johns Hopkins University - Center for Child & Community Health Research

Location: Baltimore, Maryland, United States

Completion Date: August 2010

HIA Report: Zoning for a Healthy Baltimore: A Health Impact Assessment of the Transform Baltimore Comprehensive Zoning Code Rewrite

Summary of the HIA

Proposed Policy or Project

The purpose of this project is to conduct an HIA of the Baltimore zoning code rewrite in order to maximize the potential for the zoning recode to prevent obesity and other adverse health outcomes and reduce inequities in these outcomes among children and adolescents in Baltimore. This HIA will generate transferable knowledge about how zoning can be used to improve child health in urban environments and how to optimize the utility of HIA's in informing and influencing policy processes. Obesity, crime, safety, and other related outcomes will be measured. Specific recommendations to address the key health impacts identified will be given to local stakeholders and residents.

Background and Policy Context

In Baltimore, zoning is regulated through a City Council ordinance that is administered by the Department of Planning. In 2007, the city began a 3-year project to revise and modernize its zoning code, which was late updated in 1971. This process is known as the Transform Baltimore zoning code rewrite. Modernization of the city's zoning code is mandated by the city's comprehensive plan, which was completed in 2006. 

The Baltimore City Health Department (BCHD) has been working in collaboration with the Public Health Working Group since 2008 to promote the incorporation of public health objectives into the zoning code rewrite. This collaboration helped to identify the potential role for a HIA in influencing this major zoning revision. While many HIAs have looked at built environment policies, most involved specific development projects. This is among the first HIAs to evaluate a major revision of a municipal zoning code in the US. 

Scope and Methods

The methods for this HIA include:

  • Interviews with stakeholders and decision-makers including planners, developers, and elected officials. 
  • Assessment of baseline health and socioeconomic conditions in Baltimore. 
  • Literature review of the scientific evidence related to the health impacts of the built environment features governed by zoning.
  • Analysis comparing the current zoning code and the draft new code, with emphasis on the health impacts of the draft new code. 
  • Quantitative assessment of the maximum potential impact of the draft new code on the built environment
  • Development of recommendations based on analysis results and expert opinions. 

Following the scoping interviews with stakeholders & decision makers, the Transform Baltimore HIA focused on the following pathways:

  • Violent Crimes
  • Obesity and obesity-related illnesses
  • Physical actvity
  • Pedestrian safety
  • Diet & nutrition

Summary of Findings

Literature review found evidence that:

  • off-premise alcohol sales outlets are associated with increased crime. 
  • pedestrian-oriented environments are associated with lower crime rates, increased walking and decreased obesity. 
  • mixed land use is associated with increased walking and decreased obesity, but more so for higher income than lower income populations. 
  • Increased availability of healthy food options, such as supermarkets and farmers markets, are associated with healthy eating behavior and decreased obesity rates. 

Decisions/Actions following the release of the HIA

Transform Baltimore Draft Zoning Maps are currently in the public comments period. Please go to the following link if interested:

Products Produced

Policy Brief: 


Rachel LJ Thorton, MD, PhD

Project Director


(410) 614-2908