Humboldt County General Plan Update Health Impact Assessment

Authors: Human Impact Partners, Humboldt County Public Health Branch, Humboldt Partnership for Active Living

Location: California, United States

Completion Date: March 2008

HIA Report: Humboldt County General Plan Update Health Impact Assessment

Summary of the HIA

Proposed Policy or Project

Humboldt County, a rural county in Northern California, was updating their General Plan. The General Plan Update (GPU) had three growth alternatives to accommodate future population: 1) denser development in urban areas, 2) some growth to exurban areas, and 3) unrestricted growth throughout the county.

Background and Policy Context

Humboldt County had a population of about 126,000 in the 2000 Census. The county has three urban centers, the largest one with about 26,000 people. Humboldt has a history of having major timber industry, though it is now in decline. Every 20 years the county updates its General Plan and there is active participation from the Humboldt community. After the Public Health Branch presented information to the Board of Supervisors about the relationship of the built environment and health, the Board requested that the Public Health Branch be involved in the GPU.

Scope and Methods

The HIA ultimately commented on six sections of the GPU: housing, transportation, public infrastructure, healthy economy, public safety and social cohesion, and environmental stewardship. Within these six domains, there were 35 indicators of healthy development (identified through the Healthy Development Measurement Tool) identified with data specific to Humboldt County, and focus groups of 50+ community groups and members were conducted. The HIA compared quantitatively and qualitatively what the three alternative growth scenarios would mean for the healthy development indicators based on population growth numbers provided through the Department of Finance and urban and rural population counts as defined by the Census.

Summary of Findings

In general, the most compact growth alternative was the most healthy in terms of the 35 indicators identified. For example, with the indicator of vehicle miles traveled (VMT), the HIA found that concentrating growth in urban areas (Alternative A) would result in the least amount of increase in VMT. In contrast, Alternative B (some exurban growth) would mean that 200 million more miles would be driven annually, and Alternative C (unrestricted growth) would mean that 400 million more miles would be driven annually.

Decisions/Actions following the release of the HIA

There have been many positive outcomes of the HIA. The Public Health Branch and community groups communicated the results of the HIA widely, through meetings with the Board of Supervisors, and at over 50 community meetings, conferences, and more. The Housing Element ultimately increased the amount of affordable housing due to the HIA's results, and the Transportation Element took some of the HIA research and findings and included it in that section. The HIA was included as an appendix to the GPU. Collaboration between the PHB and the Planning Department was positively initiated, and other collaborative efforts have taken place. Community engagement and education about the links has been widespread. The final decision about which alternative the GPU will adopt is still pending.

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Background Reports


Kim Gilhuly

Project Director

304 12th Street, Suite 3B

(510) 452-9442