April 17 (Reuters) - U.S. railroad operator CSX

reported first-quarter earnings above Wall Street estimates on

Wednesday, helped by higher intermodal volumes and coal export

demand, sending its shares up 2% in after-hours trading.

The Jacksonville, Florida-based company's net earnings fell

to $893 million, or 46 cents per share, for the quarter ended

March 31, from $987 million, or 48 cents per share, a year

earlier.

However, it narrowly beat profit estimates of 45 cents per

share, according to LSEG data.

Revenue slipped 1% to $3.68 billion, but it was slightly

above analysts' average expectations of $3.67 billion.

The year-on-year fall was due to lower fuel surcharge,

weaker trucking revenue and reduced export coal prices, which

offset gains in merchandise pricing and higher intermodal and

coal volumes.

The company reported quarterly merchandise volumes of

645,000 units, marginally down from 647,000 units a year ago.

Its total coal shipments were up 2% at 21.2 million tons, while

domestic shipments were down 17% on the back of replenished

utility stockpiles and weaker natural gas prices.

Unfavorable winter weather and the recent collapse of

Francis Scott key bridge in Baltimore posed infrastructure and

operational challenges to railroads, which continue to operate

in an elongated freight downcycle.

Earlier this month, CSX said it was starting a new freight

rail service between Baltimore and New York in order to

circumvent the closure of the Port of Baltimore following the

bridge collapse.

It also said its existing coal customers should expect

"potential shipment delays" after the accident and added that it

plans to keep its Curtis Bay coal pier operational, which is

located near the site of the accident.

The company's operating margin came in at 36.8% for the

quarter, down 2.7% from a year earlier.

CSX's East Coast competitor Norfolk Southern ( NSC ) is

scheduled to report its first-quarter results on April 24.