John D. Porter
Senior Vice President and Chief Financial Officer at Williams Companies
Thanks, Alan. Starting here on Slide four with a summary of our year-over-year financial performance. Beginning with adjusted EBITDA, we saw a 19% year-over-year increase. As we'll see on the next slide, our adjusted EBITDA growth included growth of over $100 million from our core large-scale natural gas transmission and gathering and processing businesses, including new records for both gathering and contracted transmission capacity. But it also included strong performance from our Sequent gas marketing business which dramatically overcame a perfect storm of severe winter weather impacts on our Wyoming businesses. Those Wyoming impacts included hits to both upstream and gathering and processing volumes as well as our Southwest Wyoming gas processing margins which were much lower from a surge in January shrink replacement gas price.
Our adjusted EPS increased 37% for the quarter, continuing the strong growth we've had in EPS over the last many years. Available funds from operations, AFFO growth was even better than adjusted EBITDA at 22% year-over-year. Also, you see our dividend coverage based on AFFO was a very strong 2.6 times and on a dividend that grew 5.3% over the prior year. Our balance sheet continues to strengthen with debt to adjusted EBITDA now reaching 3.57 times versus last year's 3.81 times. And that's even after closing the trade, NorTex and MountainWest acquisition and also repurchasing $83 million of shares since last year. On growth capex, you see an increase over first quarter last year primarily reflecting the progress we're making on some of our key growth projects, including Regional Energy Access and Louisiana Energy Gateway.
So before we move to the next slide and dig a little deeper into our adjusted EBITDA results for the quarter, we'll provide a few updates to our 2023 financial guidance. No change to our consolidated adjusted EBITDA guidance of $6.4 billion to $6.8 billion or any of our other consolidated financial performance metrics. Looking further into the year, our core transmission and gathering and processing businesses should see some additional growth from the first quarter level. For transmission in Gulf of Mexico, we'll see some ramp from a full quarter of MountainWest Pipeline and some other smaller sequential improvements through the rest of the year that should allow for a strong finish to the year. In the Northeast, we're expecting a modest increase toward the end of the year from the first quarter EBITDA level, primarily from our higher-margin liquids-rich systems.
Overall, though, we're not counting on a lot of additional growth in the Northeast from this $470 million first-quarter level, which was up 12% over the prior year. In the West, we are expecting some modest increases through the remainder of the year from the $286 million first-quarter level, especially reflecting improvement from some of the challenges we saw in the first quarter, which we'll discuss further on the next slide. For the marketing business, we've had a strong overall start to 2023. And importantly, hitting the midpoint of our guidance doesn't rely on any additional EBITDA from Sequent at this point. With respect to the upstream joint venture EBITDA guidance, it's been a tough start to our Wyoming operations with the extremely difficult winter weather that significantly impacted producing volume and our drilling plans. So we see this business likely trending toward the lower half of the $230 million to $430 million guidance range. But to be clear, for our consolidated adjusted EBITDA, we are still focused on hitting at least the midpoint of our guidance range at $6.6 billion. We are increasing our growth capex by $200 million to reflect the acceleration of our largest Transco project, Regional Energy Access, which we hope to bring into partial service later this year.
Early partial in-service for regional energy access won't have a huge impact on 2023 and is really just upside to our hitting the midpoint of our guidance for EBITDA. So let's turn to the next slide and take a little closer look at the first quarter results. Again, the first quarter matched our expectations for a very strong start to the year with 19% growth over the prior year. Walking now from last year's $1.512 billion to this year's record $1.795 billion, we start with our upstream joint venture operations that are included in our Other segment which were up only $3 million over last year. Our Haynesville upstream EBITDA was up about $32 million as there was really very little production in the first quarter of last year. However, the Haynesville increase was offset by lower Wamsutter results due primarily to the historically difficult winter weather we saw in Wyoming this year. In fact, we estimate overall weather-impacted volumes during the first quarter were probably about 3.5 times what we normally expect. And of course, that impact flowed through to our Wamsutter gathering and processing assets as well. Shifting now to our core business performance.
Our transmission in Gulf of Mexico business improved $31 million or 4%, due primarily from the partial contribution from the MountainWest Pipeline acquisition, which closed on February 14, and a full quarter from the NorTex acquisition. Our Northeast Gathering & Processing business performed very well with a $52 million or 12% increase driven by a $73 million increase in service revenue. This revenue increase was fueled by a 7% increase in total volumes in the Northeast focused in our liquids-rich areas, where we tend to have higher per unit margins than our dry gas areas. And in the appendix, you'll find a slide that compares our 7% volume growth to the overall basin growth of just under 2%. Shifting now to the West, which increased $26 million or 10% benefiting from positive hedge results and a full quarter of the Trace acquisition. But the West was significantly unfavorably impacted by the severe Wyoming weather and January processing economics at our Opal Wyoming processing plants.
Overall, gas processing margins were $44 million lower this year than last, and that was largely a January phenomenon. All in the West was about 3% short of our plan, although the winter weather impact was much worse than we had planned. And then you see the $165 million increase in our gas and NGL marketing business. And at our Analyst Day, we did point to a strong start to the year for this business due to the economics that we saw around our year-end Sequent transportation and storage positions. Ultimately, the $231 million for gas marketing was driven by positive transportation margins across all regions and strong storage margins that benefited from the lower cost or market write-down we discussed in the fourth quarter review. So again, a strong start to 2023 with 19% growth in EBITDA, driven by core infrastructure business performance with strength from our marketing business that dramatically overcame weaker-than-expected results from the upstream joint ventures.
And with that, I'll turn it back to Alan.
