Kevin Boone
Executive Vice President and Chief Commercial Officer at CSX
All right. Thank you, Mike, and good afternoon, everyone. The team continues to build momentum with our customers, targeting mobile share conversion and quickly bringing solutions to the market that target profitable growth. Our ability to react quickly and provide solutions for our customers was highlighted by our efforts in Baltimore, where we rapidly stood up an alternative solution to meet the intermodal needs of the community.
Despite a continuing weak truck market, the team has done a great job focusing on developing new opportunities, including truck-to-rail conversion, industrial development, working closer with our rail partners to identify joint opportunities, and accelerating strategic discussions that allow our customers to benefit from our best-in-class service.
Communication and collaboration between sales and marketing and operations is a key differentiator for CSX. Our recent voice of the customer survey results for the first quarter shows the highest service scores since we began the survey, which highlights the positive trajectory that we are on.
Let's turn to Slide 7 to look at our merchandise performance. Our merchandise revenues were up 1% compared to last year with flat volumes and a 1% increase in RPU as contract renewals and slightly favorable mix more than offset the effect of lower fuel surcharge. Across the business lines, automotive accelerated nicely after a slow start at several manufacturing plants.
Chemicals, our largest market continues to gain momentum in plastics, food, and NGLs. Orange product volumes were flat overall but saw encouraging signs in pullboard and building products as the construction season appears to be off to a stronger start. We told you that minerals face a tough comparison for aggregates, which were unseasonably strong in the first quarter of 2023.
But total demand is very strong against a healthy backlog of large construction projects with infrastructure spending expected to accelerate. Metals volumes were a bit weaker year-over-year with the weather affecting flows in certain scrap markets. Finished steel has also been a bit sluggish, but we see opportunity for sequential improvement in the back half of the year.
Fertilizer volumes continue to be unimpacted by phosphate production issues here in Florida, but an early application season in certain markets supported demand for longer-haul, higher-yield shipments of potash and other fertilizers, which lifted our RPU.
Finally, our Ag and food business remains relatively soft, constrained by a strong global soybean supplies, which limit demand for U.S. exports and still high availability of local crops in many of our customer regions. Underlying demand across grains, feed, and food products is solid and we're optimistic challenging conditions will normalize into the back half of the year.
Turning to Slide 8. For the first quarter, coal revenue was flat year-over-year as 2% volume growth was offset by a 2% decline in all-in RPU, largely due to fuel surcharge. Our benchmark-based export yields were slightly lower compared to last year, but we also got some benefit from favorable mix on the domestic side.
As expected, shipments reflected the strength in export markets with export tonnage up 25% year-over-year. It really is a testament to the great work by the team, including the credible work by operations to meet the increased demand. We also anticipated that the domestic market would be challenged by low natural gas prices and lapping last year's restocking demand.
Domestic shipments for the quarter were down 17% against a very tough comparison in the first quarter of 2023. With Baltimore and the effects of the collapse of the key bridge, I'm going to stress how important our partnership is with the city. As Joe noted before, we have a long history with Baltimore, going back to the very beginning of our railroad. And the ONE CSX team is working hard to find alternative solutions to help the community and our customers. In terms of the revenue impact to CSX, export coal will see a near-term headwind with both our Curtis Bay facility and the dual-serve console marine terminal that are unable to load vessels.
Two days following the incident, Joe and I joined senior leadership from CSX to visit key alternative export facilities. We have already begun to divert a portion of our Baltimore volumes to other outlets. Currently, we estimate that the net revenue impacts to CSX from the port closure is between $25 million and $30 million per month, including the benefit of diverting some of these tons. It's still very early in the remediation process, but the Army Corps of Engineers has projected that the full channel depth, which we need for coal vessels to be reopened by the end of May.
It's also likely that you see a good amount of congestion immediately after reopening, but there's potential for it to take a few weeks to ramp back up to full run rate. In the meantime, we are studying in communication with our customers, business partners, state, local, and federal authorities. Growth was very strong for our international business as healthy consumer demand and more normalized inventories have supported higher import levels.
We saw volumes increase year-over-year with many of our shipping partners as we gained from new contracts, new lanes, and a comparison with last year's weak market conditions. We are very encouraged by the recovery we are seeing and continued positive demand signals as we look over the rest of the year.
Our domestic intermodal business also grew over the quarter at a more moderate pace than what we've seen over the last couple of quarters. What's been constant is our service performance, which continues to help us win new business and drive truck conversion even as the weak truck market conditions persist. We're optimistic that truck capacity will normalize in time and benefit the intermodal market. More importantly, we are confident that we will be prepared when the demand rebounds.
Finally, let's turn to Slide 10, where we have an update on our industrial development program. Our project pipeline remains strong with 100s of companies eager to partner with us to find attractive ways to expand their production capacity on rail surf sites. Something that's often overlooked is how diverse these development projects really are.
The chart on left shows the market split. Based on potential carload volume for the approximately 100 facilities that have come online over the last 12 months, these new sites and expansions represent $4.2 billion in total capital investment and have added new capacity in many of our key markets such as chemicals, minerals, and forest products.
But this is only scratching the surface. The chart on the right shows the market split for the full development pipeline ranging from projects we anticipate starting up later this year to project proposals that will be constructed several years from now. There are two key takeaways from this forward-looking view. First, the total estimated potential carload opportunity measured by expected capacity implies a meaningful acceleration in activity as we look forward. Scopes can change and timelines can shift, but the setup is very encouraging for meaningful growth contribution over multiple years.
Second, the long-term pipeline is also diverse. We are excited about the multiple electric vehicle manufacturing facilities that are scheduled to come online over the next several years. When combined together with related raw material or battery facilities, they represent approximately 12% of the total long-term volume potential. Minerals, metals, chemicals, and other projects represent larger contributors. This is a big opportunity for CSX and our industrial development team has been working non-stop to build the partnerships that make all of this possible. We're excited to tell you that there's much more to come.
With that, let me turn it off and let me hand it over to Sean. Thank you.
