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(Corrects spelling of analyst's last name to Forrest, notForest, paragraph 9)
* Sept WCS trades at $19.45/bbl below WTI
* Sept synthetic trades at $4.75/bbl below WTI
By Nia Williams
CALGARY, Alberta, Aug 13 (Reuters) - The outright price ofCanadian heavy crude was mired near its lowest level in at leasta decade on Thursday, keeping pressure on producers in westernCanada who are increasingly hard pressed to cover production,transportation and blending costs.
The discount on Western Canada Select heavy blend crude forSeptember delivery narrowed slightly after Enbridge Inc reopened its 600,000 barrel per day Flanagan South pipeline inthe U.S. Midwest.
Flanagan South is one of the key conduits for Canadian crudeto reach the U.S. oil futures hub at Cushing, Oklahoma, and theGulf Coast.
Its closure along with the adjacent Spearhead line after aspill on Tuesday prompted a blow out in WCS differentials totheir widest level this year at $21.75 per barrel below the WestTexas Intermediate benchmark.
WCS last traded at $19.45 per barrel below U.S. benchmark,according to Shorcan Energy brokers, tightening from asettlement of $19.90 per barrel below on Wednesday.
That put the outright price of Canadian crude at around$22.78 a barrel, with U.S. crude closing down 3 percent at$42.23 a barrel after data showed a big rise in key U.S. crudestockpiles.
On Wednesday the outright price of Canadian crude slumpedintra-day to around $22.50 a barrel.
Canada's oil sands hold the world's third largest crudereserves after Saudi Arabia and Venezuela, but carry highoperating costs because of energy-intensive production methods.
ARC Financial analyst Jackie Forrest estimated the averagecash costs for a thermal oil sands would be in the range of $25a barrel, once operating costs, blending costs and the cost oftransporting crude to the marketing hub of Hardisty, Alberta,are combined.
WCS differentials also came under pressure this week fromunplanned maintenance at BP Plc's Whiting, Indiana,refinery, which is one of the largest consumers of Canadianheavy crude.
Light synthetic crude from the oil sands for Septemberdelivery narrowed to $4.75 per barrel below WTI from Wednesday'ssettlement of $5.15 a barrel below the benchmark. (Editing by David Gregorio)
