* Line to Houston Ship Channel terminal hub under construction * Alleviate bottlenecks when finished in 2H 2013 HOUSTON, Jan 31 (Reuters) - Enterprise Products Partners LP expects a new oil pipeline connecting the recently expanded Seaway Pipeline to Houston refineries to be completed in the second half of the year, company officials said on Thursday. The completion of the line should help ease a bottleneck at the Jones Creek, Texas, terminal, at the end of the Seaway line, which currently has only two options to take away crude from storage tanks. Seaway operator Enterprise was forced last week to reduce throughput on the southern leg of Seaway after the Phillips 66 247,000 barrels-per-day (bpd) refinery in Sweeny, Texas, went into maintenance. The link to Sweeny is one of two pipelines that can draw crude from Jones Creek. The lateral pipeline from Jones Creek to Enterprise's ECHO terminal on the Houston Ship Channel is slated to be completed in the third or early fourth quarter this year, Bill Ordemann, group senior vice president of unregulated natural gas liquids, crude and natural gas assets, said during the company's fourth-quarter earnings conference call. The recently expanded Seaway pipeline can carry up to 400,000 bpd of crude to the Jones Creek facility from Cushing, Oklahoma, the delivery point of the benchmark U.S. crude contract. The curtailment order issued by Enterprise restricted flows to an average of 175,000 bpd on that final leg of the pipeline into Jones Creek. Ordemann said Seaway was operating as designed, and the new lateral "will have the ability to alleviate most of the bottlenecks we're seeing right now." U.S. crude futures fell sharply relative to international benchmark Brent on expectations the reduced Seaway throughput would increase inventories at the Cushing hub. Stockpiles at Cushing have swelled to record levels as rising volumes of crude produced in North Dakota and Canada pour into the hub, which has limited capacity to move it to the Gulf Coast refining center. Enterprise, which co-owns Seaway with Enbridge Inc, said the penultimate delivery point on the pipeline in Katy, Texas, can compensate for restrictions at Jones Creek. Ordemann also told analysts that the line's flow has fluctuated since the expansion started up earlier this month, with the high point at 380,000 bpd. Further relief to the bottleneck at Jones Creek could come from plans for Phillips 66 to run higher volumes of sweet crude at the Sweeny plant, which could mean it takes more oil from Seaway. Seaway can carry both light and heavy oil. On Wednesday Phillips 66 Chief Executive Greg Garland told analysts that the company was looking at running all sweet crude at Sweeny. It is primarily a heavy crude refinery that can run up to 60,000 bpd of sweet crude now, he said. An investment of up to $50 million would help increase its ability to process sweet crude, he said.