Unconventional Drilling Activity Down In Pennsylvania

By Matt Kelso, Manager of Data & Technology

Wells Spudded (Drilled)

The number of newly drilled unconventional wells in Pennsylvania peaked in 2011.

Figure 1: Newly drilled unconventional wells in Pennsylvania peaked in 2011.

Unconventional oil and gas drilling is well established in Pennsylvania, with over 9,200 drilled wells, an additional 7,200 permitted locations that have not yet been drilled, and 5,300 violations all happening since the turn of the millennium. It took a while for the industry to gather steam, with just one unconventional well drilled in 2002, and only eight in 2005. But by 2010, that figure had ballooned to 1,599 wells, which was greater than the previous eight years combined. There were 1,956 wells drilled in 2011, representing the peak for unconventional drilling activity in Pennsylvania (Figure 1).

None of the three full years since then, however, have seen more than 70% of the 2011 total. Halfway through 2015, the industry is on pace to drill only 842 unconventional wells statewide, which would be the lowest total since 2009, and only 43% of the 2011 total.

Pennsylvania Shale Viewer. Click here to access the full screen view with a legend, layer details, and other tools.

Taken cumulatively, the footprint on the state is immense, as is shown in the map above, and impacts remain for some time. Of Pennsylvania’s 9,234 unconventional wells 8,187 (89%) are still active. Only 474 wells have been permanently plugged so far, with 570 given an inactive status, and one well listed as “proposed but never materialized,” despite being included on the spud report.

Permits & Violations

The number of permits and violations issued have been declining over the past five years as well.

Five years of unconventional oil and gas activity in Pennsylvania, July 2010 through June 2015.

Figure 2: Five years of unconventional oil and gas activity in Pennsylvania, July 2010 through June 2015.

Figure 2 shows the monthly totals of permits, wells, and violations over the last 60 months. Linear trendlines were added to the chart to give a visual representation of changes over time if we ignore the noise of the peaks and troughs of activity, which is an inherent attribute of the industry. Each of the three trendlines has a negative slope1, showing downward trends in each category.

In fact, permits for new wells are declining more rapidly than the drilled wells, and violations issued are declining at a still faster rate. Over the course of five years, these declines are substantial. In July 2010, the smoothed totals that are “predicted” by the trendline show 304 permits issued, 159 wells drilled, and 128 violations issued per month.  60 months later, one would expect 213 permits, 81 wells drilled, and just 12 violations issued2.

Location of Drilling Activity

The oil and gas industry has been more selective about where unconventional wells are being drilled in recent years, as well. Altogether, there are unconventional wells in 39 different counties, with 32 counties seeing action in both 2010 and 2011. That number is down to 22 for both 2014 and the first half of 2015. There has been drilling in 443 different municipalities since 2002, with a maximum of 241 municipal regions in 2011, which shrank to 161 last year, and just 88 in the first half of 2015.

Summary of unconventional wells drilled in each Pennsylvania county by year, through June 30, 2015. Click here to access the full screen view with a legend, layer details, and other tools

Clicking on any of the counties above will show the number of unconventional wells drilled in that county by year since the first unconventional well was spudded in Pennsylvania back in 2002.  The color scheme shows the year that the maximum number of unconventional wells were drilled in each county, with blues, greens, and yellows showing counties where the activity has already peaked, oranges showing a peak in 2014, and red showing a peak in 2015, despite only six months of activity.  30 of the 39 counties with unconventional wells in the state saw a peak in activity in 2013 or before.


  1. The equations for the three trendlines are as follows:
    • Permits: y = -1.5128x + 303.81
    • Wells: y = -1.2939x + 158.95
    • Violations: y = -1.9334x + 127.53
  2. The lowest actual value for each category are as follows:
    • Permits: 117, in July 2012
    • Wells: 43, in February 2015
    • Violations: 16, in August 2014.