Kevin L. Burdick
Executive Vice President and Chief Commercial Officer at ONEOK
Thanks, Walt. Let's start with our natural gas liquids segment. Second quarter 2023 NGL volumes increased 11% year-over-year and compared with the first quarter 2023. Higher volumes were driven by increased producer activity, particularly in the Rocky Mountain region and Permian Basin. Both regions saw double-digit volume increases year-over-year and compared with the first quarter of 2023. Permian Basin volumes saw the largest increase, up 26% year-over-year, driven by continued growth from existing plants and volume from a new plant connection in the first quarter of 2023.
Volumes in the Rocky Mountain region increased 17% compared with the first quarter of 2023 and 14% compared with the same period last year, driven by increased propane plus volume and slightly higher incentivized ethane. MidContinent region volumes increased 8% compared with the first quarter of 2023, partially driven by increased ethane recovery. While we've seen ethane prices decreased recently from July highs, they remain at a level driving recovery in most basins. We think the recent volatility in ethane pricing is the market responding to some short-term dynamics along with the general tightening in the overall supply and demand balance. Given these market conditions, we remain confident in our ethane recovery assumptions included in our updated guidance. The Permian in near-full recovery, the MidContinent in partial recovery and opportunities to incent recovery in the Williston.
As Walt mentioned, we've begun initial work, including purchasing long-lead time components for two NGL pipeline expansion projects. Activities are underway to complete the looping of West Texas NGL pipeline, which will more than double ONEOK's NGL capacity out of the Permian Basin. The full loop is expected to be in service in the first quarter of 2025, which aligns with our customers' needs. We also are taking steps towards expanding the Elk Creek pipeline to 400,000 barrels per day to provide capacity for growing volumes in the Williston.
In the natural gas gathering and processing segments, second quarter processed volumes averaged nearly 2.2 billion cubic feet per day, a 16% increase year-over-year. In the Rocky Mountain region, processed volumes averaged nearly 1.5 billion cubic feet per day during the second quarter and have averaged more than 1.5 BCF per day in the month of July. We've connected more than 280 wells in the region through the first half of the year compared with approximately 160 connections in the first half of 2022, a 75% increase.
As we sit today, we're on pace to reach the high-end of our 475 to 525 well connect guidance range for the year. Currently, there are approximately 35 rigs and 20 completion crews operating in the basin with 19 rigs in approximately half of the completion crews on our dedicated acreage, which remains more than enough activity to grow production on our acreage.
In the MidContinent region, second quarter processed volumes increased 12% year-over-year and decreased slightly compared with the first quarter of 2023, primarily due to the timing of new pads coming online. We've seen some recent decreases in STACK and SCOOP activity in the past few months, but continue to see increased activity in Western Oklahoma as producers are focusing on higher crude producing areas. We currently have nine rigs on our dedicated acreage in the MidContinent and have connected 23 wells in the region through the first half of the year.
In the natural gas pipeline segment, the strong year-to-date results continue to benefit from demand for natural gas storage and transportation services. And we now expect the segment to exceed the high-end of its original earnings guidance range. We've recently completed an expansion of our natural gas storage capabilities in Oklahoma, allowing us to utilize and subscribe an additional 4 billion cubic feet of our existing capacity. We have subscribed 100% of this incremental capacity through 2027 and 90% through 2029.
We continue to evaluate the Saguaro Connector pipeline, a potential intrastate pipeline project that would provide natural gas transportation to the US and Mexico border for ultimate delivery to an export facility on the West Coast of Mexico. There continues to be positive developments related to the potential LNG export project with support from multiple large well known customers, anchoring the project. We expect to make a final investment decision on the ONEOK pipeline later this year.
Now, I want to end where Pierce left off, with a micro look at the Magellan transaction synergies. I will discuss how we define each category, an example of the opportunity, the sensitivities and comments on the overall risk-weighting. The dollar ranges between our assumed case and the near-term potential are shown on Page 6 of our investor presentation for all four categories.
Liquids pipelines provide opportunities to move natural gas liquids and refined products through the same product pipelines. Both companies refer to this as batching. This operational technique utilizes available capacity and combined connectivity to ship a refined product or natural gas liquid to a demand center to capture a higher value. An annualized average of 100,000 barrels per day in any combination of refined products or NGLs at $0.07 per gallon would result in more than $100 million annually.
The ability to mix products to obtain a higher value is called blending. The combined assets will increase unleaded butane blending as well as other incremental blending opportunities. Increasing an additional 25,000 barrels per day annually at a $0.20 per gallon uplift on any given slate of products or NGL would result in approximately $75 million, annually.
As volumes grow or contracts expire, a wider variety of services can be combined or bundled to offer greater value to customers. This focuses on optimizing system utilization and connectivity to and from key customers and market centers. This is the one category where time and decisions, primarily by customers, will jointly be needed to realize this synergy, picking up an incremental 25,000 barrels per day at $0.10 per gallon would provide approximately $40 million a year.
Additional opportunities that can be realized within the one to four year timeframe include incremental refined product, NGL and crude oil, storage and optimization activities. We also see value and opportunities to leverage Magellan's proven marine export expertise. We have consistently said that acquisitions of this size often result in a 25% reduction in G&A cost, which in this case would be $200 million. However, we have assumed only $100 million in both the assumed case and the near-term potential case.
It's also important to point out when the transaction was announced, we significantly risk-weighted our financial assumptions to come up with our total assumed $200 million of synergies. This should highlight the level of conservatism we've applied to our expectations and also the potential upside to our assumptions, which we think could drive synergies to more than $400 million. As we've said previously, we have a high level of confidence in achieving the assumed $200 million of near-term synergies.
For obvious commercial reasons, we're not going to provide specific project level details at this time. However, we have provided realistic potential outcomes by categories. We believe our ability to batch and blend products on our combined pipeline systems as well as bundled services to increase value for customers will provide significant synergy opportunities over the next one to four years.
Pierce, that concludes my remarks.