Enterprise Products Partners LP (EPD) cut its Seaway pipeline oil deliveries by more than half after a major refinery in Sweeny, Texas, reduced demand while it undergoes maintenance, an Enterprise spokesman said Thursday.

Enterprise reduced the flow of its newly expanded 400,000 barrel-a-day pipeline Wednesday to 175,000 barrels a day because its Jones Creek storage terminal was filled to capacity.

The reduction was not because of technical problems with Seaway, or with the terminal, but because customers were not taking enough oil out of the terminal, Enterprise spokesman Rick Rainey said.

"This is not a Seaway issue--we can still transport 400,000 barrels a day," Mr. Rainey said. "There is at least one downstream issue that we are aware of."

Phillips 66 (PSX) has taken its 247,000 barrel-a-day refinery in Sweeny offline for planned maintenance, Phillips spokesman Rich Johnson said. Mr. Johnson declined to say how long the refinery would be down or whether the maintenance was directly related to the backup at the Jones Creek terminal.

Houston refiners can still receive Seaway oil from the pipeline's storage terminal in Katy, Texas, Mr. Rainey said.

The pipeline carries crude from Cushing, Okla., the delivery point for the benchmark U.S. crude futures--West Texas Intermediate, or WTI. A glut of oil there has driven down WTI prices over the past two years. The longer the pipeline is unable to transport crude from Cushing, the more likely WTI prices will fall, traders and analysts said.

Wednesday, WTI futures fell 1.5% after the Seaway reduction was announced, its biggest decline in a month, in part because Seaway's problems would let crude levels build up in Cushing.

Write to Ben Lefebvre at ben.lefebvre@dowjones.com

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