Pipeline Right-of-Ways: Making the Connection between Forest Fragmentation and the Spread of Lyme Disease in Southwestern Pennsylvania

Lyme disease has been a growing concern across the United States as cases have continued to spread in recent years. While many ecological factors may contribute to the spread of Lyme disease, two of the most significant factors are believed to be climate change and forest fragmentation.

This study uses multiple linear regression to assess the role that different pipeline construction proxies play in the change in average annual Lyme disease rate in Pennsylvania counties from 2001 to 2019. The findings of this research suggest a possible relationship between one of the pipeline proxies (the cumulative number of wells drilled in each county) and change in average annual Lyme disease rate.

Oil and Gas Pipelines and Lyme Disease Rates

At the beginning of the 21st century, Lyme disease was only concentrated in small pockets of Pennsylvania. However, over the past 20 years, cases have spread to every county in the state. A major contributing factor to the spread of cases in southwestern Pennsylvania could be increased forest fragmentation caused by pipeline right-of-ways. Oil and gas pipelines require that 50 to 100 feet right-of-ways be cleared for the entire length of the pipeline. Fracking has increasingly dominated the region since the early 2000s, meaning that the need for new pipelines has also grown.

Mapping Variables Used in This Study

This interactive map looks at the cumulative number of wells drilled, total change in forest edge, total change in forest cover, and average annual change in population from 2001 to 2019 in each Pennsylvania county, which were all inputted independent variables in a multiple linear regression model against the dependent variable of observed average annual change in Lyme disease rate.

View the map “Details” tab below in the top right corner to learn more and access the data, or click on the map to explore the dynamic version of this data. Data sources are also listed at the end of this article.

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• Lyme disease has spread throughout the entire state of Pennsylvania over the past two decades.
• Research done by the U.S. Geological Survey indicates that approximately 67% of new forest fragments in southwestern Pennsylvania from 2000 to 2010 could be attributed to natural gas infrastructure.
• Forest fragmentation and climate change are believed to be key contributors to the spread of Lyme disease.
• Data on the construction of pipelines over time in Pennsylvania is not well documented, so it is difficult to know whether forest fragmentation caused by pipeline right-of-ways is contributing to the spread of Lyme disease or not.

The results of this study indicate that there may be an association between the construction of pipeline right-of-ways and Lyme disease rates, however, more research is recommended to validate these findings. This research is intended to bring attention to the influence that oil and natural gas infrastructure might have on the spread of Lyme disease, but also on the need for better data on pipelines. Efforts have been made to map the locations of gathering lines, but the data that has been collected is by no means complete (FracTracker Alliance, 2020). In order to understand the health impacts that pipelines have on communities, it is essential to have quality data on where they are located.

Read the full study by FracTracker Environmental Health Fellow Ana Abel below.

Acknowledgements

Support for this research provided by FracTracker Alliance. Funding for this fellowship provided by Community Foundation for the Alleghenies and The Heinz Endowments.