Photo by Kyle Walton.

In addition to the security upgrades part and parcel for the anniversary of the September 11 attacks, Metrorail riders will have some track maintenance to deal with over the weekend.

Riders on the Red, Blue, Orange and Green lines will experience single-tracking beginning at 10 p.m. this evening along the following sections of track:

>> Red Line: between Dupont Circle and Judiciary Square
>> Blue/Orange Lines: between Eastern Market and Stadium-Armory
>> Green Line: between Greenbelt and College Park

Additionally, the last Shady Grove-bound train on the Red Line will depart from Glenmont 11 minutes earlier than usual every night this weekend — so those of you who plan on staying out late, take note. In general, WMATA estimates that riders should add between 20 and 30 minutes of travel time if they’re planning on traveling along any of those sections of track. All work will last through the end of service on Sunday.

There are also a few bus detours in place for the weekend — details on those can be found here.