An East Hampton man who was charged on Sunday with driving while intoxicated, his third such arrest in eight years, could face “significant” jail time if convicted of the felony charges he is facing.East Hampton Town police stopped Dalton D. Donegal, 39, a little before midnight on Three Mile Harbor Road in East Hampton, saying he was speeding and swerving across the double yellow line. Back at Wainscott headquarters his breath test reportedly produced a reading of .18.Because Mr. Donegal was convicted of misdemeanor D.W.I. here in 2008, and of felony D.W.I. in county court in 2010, the latest arrest means that he faces elevated felony charges. He was arraigned on Monday morning before East Hampton Town Justice Steven Tekulsky, who told him that the district attorney’s office had asked for bail to be set at $50,000. Brian Francese, Mr. Donegal’s Legal Aid Society attorney, asked for bail of $1,000, pointing out that his client has lived in East Hampton for 15 years and has a wife and three children.“Fifty thousand is excessive,” Justice Tekulsky said, though he warned that Mr. Donegal faced “significant” jail time if convicted. He set bail at $21,000. Besides the speeding and failure to maintain lane charges, police also charged Mr. Donegal with having unsafe tires, not wearing a seatbelt, and driving a vehicle with a suspended registration.Justice Tekulsky asked him if he was going to be able to post bail. He responded that he did not think so.Mr. Donegal was in county jail in Riverside as of yesterday morning, unable to meet the bail requirement. He will be released tomorrow if no indictment against him is handed down by then. If he is indicted, either before tomorrow or after, his case will be moved to county court in Riverside.