Nighttime detours begin Sunday night at the Interstate 83 South ramps at Lowther Street in Lemoyne, according to PennDOT.
PennDOT spokesman Mike Crochunis said that because of construction activities, the Lowther Street ramp to I-83 South will be detoured for approximately two nights, while the southbound I-83 ramp at Exit 41-B will be detoured for approximately two weeks.
Drivers will be directed around the closed ramps using a signed detour between the hours of 9 p.m. and 6 a.m.
Southbound I-83 traffic to Lowther Street will be directed to Exit 42 for Lemoyne and continue straight on Lowther Street.
Route 581 traffic to Lowther Street will be directed to continue on I-83 North and take Exit 41-B for Highland Park to Lowther Street.
Lowther Street traffic headed to I-83 South will be directed to continue east on Lowther Street, enter I-83 North, proceed across the Susquehanna River to Exit 44-A for 13th Street, turn right onto 13th Street, then turn left onto the ramp to I-83 South.
The $22.1 project to improve the I-83 interchange with Route 581 is scheduled for completion in the summer of 2015.