LYNN – National Grid has begun upgrading its gas infrastructure in Lynn and the work is expected to continue through mid-September.The affected locations include Arvidson Road, Sanger Avenue and a stretch of Dartmouth Street between No. 7 and 82.According to National Grid spokeswoman Debbie Drew, approximately 1,725 feet of gas pipe will be installed. This upgrade project, designed to improve system reliability and safety, is part of the company’s overall plan to invest more than $200 million in gas main replacements across its service area through March 2010.National Grid’s contractor will perform the work in Lynn between 7 a.m. and 5 p.m., Monday through Friday. Streets will remain open, however, parking will be affected during working hours for the duration of the project.”The company will make every effort to minimize disruption to homes and businesses along the route and will employ traffic management plans and police details as appropriate,” said Drew, noting that the required work will be conducted in close coordination with town officials and public safety representatives.Customers can expect a brief service interruption upon completion of the work, as homes and businesses are connected to the new main, Drew said.Residents will be notified prior to any necessary construction on private property. Anyone with questions or concerns may contact National Grid Community Relations Coordinator John Upham at 781-907-2206.