California’s New Oil Wells Average 13.5 Barrels/Day — Far Below State Projections

Introduction

The California Governor’s Office has proposed legislation aimed at fast-tracking permits for new oil and gas wells. The bill would remove standard environmental reviews under the California Environmental Quality Act (CEQA) and eliminate bonding requirements for the transfer of non-producing wells, which increases the risk of orphaned wells and improperly abandoned infrastructure.

Last week (August 20th) at a joint oversight committee meeting of the California State Assembly, presentations to the California State Assembly provided data on current production trends and projected outcomes under the proposed legislation. The stated goal is to increase California’s annual crude oil production to 125 million barrels, based on the assumption that new wells produce an average of 30 barrels per day (bbl/day).

This analysis examines the validity of that production claim, using publicly available CalGEM data and independent calculations, and provides more accurate estimates of the number of wells required to meet the state’s production target. The study also evaluates production decline rates and incorporates the role of enhanced oil recovery and support wells in overall output.

Analysis Overview and Methods

Oil and gas production volumes were downloaded (8/21/25) from CalGEM’s WellStar database, which reports monthly totals. Spud dates for individual wells previously acquired via public records requests to CalGEM were used as reference points to estimate the start of production. The analysis was conducted using Python 3.12.7, and the corresponding notebook is publicly available (FracTracker Alliance Data Hub). The dataset was limited to wells spudded between January 1, 2019, and December 31, 2023, ensuring at least one full year of production data, with 2024 as the most recent complete production year.

Production Estimates

In 2024, the Energy Information Administration (EIA) reported that California produced approximately 104 million barrels of crude oil. Because CalGEM includes condensates in their totals, we normalized their figures against EIA crude oil estimates to ensure comparability, applying a 92.05% conversion factor (based on 2024 data) to approximate the crude oil portion of CalGEM’s reported volumes (a slightly higher total of 113 million barrels). This adjustment factored into the estimate of average production per well but did not have a substantial impact on the reported results.

To achieve the proposed target of 125 million barrels per year, California would need to increase production by 20.975 million barrels. If new wells were truly capable of producing an average 30 barrels per day (or 10,950 barrels per year), this would require an additional 1,916 production wells. The following analysis evaluates whether these assumptions align with observed well performance and realistic production data.

Annual production for each well was calculated by summing monthly volumes over the first five years following the spud date. Multi-year and individual annual averages were computed. The analysis also incorporated additional enhanced oil recovery (EOR) and support wells, which contribute to overall production, when calculating daily averages. These data were further used to estimate average decline rates.

CalGEM spud date records indicate that 786 wells drilled between 2019 and 2024 were not present in the monthly production databases. These include gas storage wells, EOR wells, and support wells necessary to maintain production volumes. To account for these, a five-year average of 157.2 additional wells per year was included in average production calculations, which had very little impact on estimates.

Maximum Possible Production Threshold

To explore how the 30 bbl/day figure may have been derived, a scenario was modeled to maximize production. Adjustments included:

• Ignoring real-world time frames and normalizing daily production by only the days a well reported non-zero output.
• Excluding support and EOR wells from the calculation.
• Removing months with zero production.
• Using raw “oilorcondensate” figures without adjustment to EIA crude oil totals.

This approach produces the highest theoretical daily production estimates but does not reflect realistic operating conditions, as it ignores downtime, support wells, and the actual elapsed time since drilling. 

Results, discussed below, showed that even under best-case assumptions—ignoring downtime and support wells—California wells would still produce an average of only approximately 21 bbl/day, 30% below the figure used in state projections.

Results

Realistic Well Productivity

New California wells average 13.52 barrels per day over the first five years, producing roughly 4,935 barrels per year. Productivity peaks in year two at approximately 14.55 barrels per day, then declines steadily. This is 55% lower than the 30 bbl/day figure cited by CalGEM. Compared with highly productive regions like the Permian Basin, where a single average well produces in three days what a California well produces in a year. The state of California production decline makes it unreasonable to drill enough wells to accomplish this goal.

Table 1. Estimates of average daily crude production for California oil wells 2019 – 2024. Averages are presented for individual years, as well as for ranges of years post-drilling.

Decline Curves

The above analysis of all CalGEM wells drilled 2019-2023 showed that over their first 5 year span of production, many California oil wells experienced a peak second year that plateaued and was then followed by a rapid decline in production. A longer eight-year analysis of wells drilled in 2016 was consistent, and showed annual declines averaging 15.5% over the first six years, then tapering as wells produce marginal volumes for the remainder of their lifespan. The trends in decline for both datasets followed the classic sigmoidal pattern. Of note, the documented decline rates were much faster than the 7% rate assumed in policy projections.

Annual production decline rates for the wells drilled in 2016 are presented in Table 2 and plotted in Figure 1 below. The data shows that decline rates during the rapid decline period were as high as 21.7% from year four to year five. Production decline rates then flattened leaving the wells to produce stripper volumes for their remaining lifespans.

Table 2. Production decline rates for California oil wells drilled in 2016.

Figure 1. The plot shows year to year production decline rates for the oil and gas production wells drilled in California in 2016.

Maximized Production Scenario

Even when adjusting assumptions to maximize production (excluding downtime, ignoring support wells, and normalizing production only over days reporting output) the highest achievable estimates were estimated at an average of 20.9 bbl/day over the five-year period, still well below the 30 bbl/day claim. Average decline rates were measured at 29.3% over the five-year period, with indications of the steepest decline rate just starting at year 5. These results demonstrate that California wells have intrinsic production limits, and ambitious targets require far more wells than policymakers anticipate, with substantial environmental and economic consequences.

Table 3. Unrealistic maximized estimates of daily crude production for California oil wells. Methods do not reflect true time frames.  Averages are presented for individual years, as well as for ranges of years post-drilling.

Conclusions

Current policy discussions significantly overestimate California oil well production. Claims of 30 barrels per day per well are nearly double the observed average of 13.52 bbl/day, with actual decline rates averaging 15.5% annually. Meeting the state’s 125-million-barrel target would require drilling an impractical count of new wells, with thousands more over the following years to maintain, generating substantial land disturbance, air pollution, and orphaned well risks. Given the low productivity relative to other U.S. regions, aggressive drilling expansion is economically inefficient. Policymakers should base decisions on realistic production data, decline rates, and environmental impacts, and consider cleaner alternatives.

Downloads

• Assessment of California Oil and Gas Production from New Wells by Kyle Ferrar (2025). Download PDF 🡥