This story has been updated.

The construction of Metro’s Silver Line extension to Dulles Airport is beginning to impact the commutes of thousands of people who park and board buses at the Herndon-Monroe Park and Ride.

Drivers in and around the area should expect changes to traffic patterns this fall as work begins on sewer and water lines that will serve the parking facility and the future Herndon Metro Station under construction in the median of the Dulles access road.

Lane shifts have already occurred in advance of excavation, which will last until at least February. Drivers should expect slow traffic and trucks entering and exiting the work area in the access road.  Precast and steel work in the spring will likely require some lane closures, a project spokeswoman said.

Meantime, commuters using the Park and Ride should expect changes to traffic patterns, the Kiss and Ride, and bus bays at the facility.

This week crews began utility relocation, and they are expected to start drilling for the utility tunnel next week.  As part of the project, the popular Park and Ride will be expanded to provide access to the new rail station expected to open in 2020.

The Herndon station is one of six under construction as part of the phase II of the Silver Line, a project of the Metropolitan Washington Airports Authority.  They new stations will extend Metro’s newest line from the Wiehle-Reston East Metro station to Ashburn, with a stop at Dulles Airport.

The impacts to the Herndon parking facility are expected to continue through the end of the year.

The Kiss & ride on the north side of the bus platform will be relocated starting next week to provide room for the drilling work, officials said. A temporary Kiss and Ride will be in place across from the garage entrance.

Some bus bays also will be relocated in coming weeks, affecting the commutes of the 3,800 people who take the Fairfax Connector buses on weekdays. The Park and Ride has 1,700 parking spaces and is served by 12 Fairfax Connector routes and a Metrobus.  The buses provide connections to Dulles and the Wiehle–Reston East Metro station.

After the utility work is completed this year, construction will start on a pedestrian pavilion and bridge that will carry pedestrians to cross over the toll road and airport access road to the rail station, project spokeswoman Marcia McAllister said.

The six stations in the project are: Reston Town Center, Herndon, Innovation Center, Dulles International Airport, Loudoun Gateway and Ashburn.