California

The graphs on the left show the rate of growth compared to the earliest year for which we have data -- in most cases 2003. The gray lines represent a theoretical constant annual rate of change. The bar charts on the right show the actual values for each year we have data. For example, in 2011, California had 2,294 new wells drilled.

Notes: Data for number of wells drilled in 2011 and total wells in 2009 and 2010 were taken from the Department of Conservation's website. The enforcement action data supplied by the state include deficiencies, violations, formal orders and civil penalties. Enforcement staff includes energy and mineral resource engineers, oil and gas technicians and engineering geologists, who are responsible for the majority of inspections. The state also employs associate oil and gas engineers for whom inspections are a minor component of their jobs. Total wells include active oil and gas wells.

BLM Data

In California, much of the oil and gas drilling takes place on land that is federally regulated, which can include national parks or Native American reservations. Data provided by the Bureau of Land Management represents wells drilled on that land.

Notes: Data are for the fiscal year.