Caltrans construction crews will close State Route 78 (SR-78) in both directions, between Indian Oaks Road and Weekend Villa Road in Ramona starting Friday, April 21.
The construction will last up to four consecutive weekends from Fridays starting at 9 p.m. until Mondays at 5 a.m.
Caltrans says that motorists can expect delays and are urged to allow extra time for travel during the closures.
The closures are needed to allow crews to construct a retaining wall to stabilize the slope on the north side of the highway.
A detour will extend from Cloverdale Road/San Pasqual Road to Main Street/State Route 67 (SR-67).
Eastbound motorists will be detoured south on Cloverdale Road/San Pasqual Road, south on Bear Valley Parkway/Via Rancho Parkway, south on Interstate 15, east on Scripps Poway Parkway and north on SR-67 to SR-78.
Westbound motorists will follow the same detour in the opposite direction.
Local traffic will still be able to access SR-78 between Cloverdale/San Pasqual Road and Indian Oaks Road and between Weekend Villa Road and SR-67/Main Street.