WASHINGTON — Red Line trains will be slowed for weeks or more near the Rhode Island Avenue  Metro station after follow up inspections tied to the station’s closure last week found additional “degraded concrete” on the bridge structure holding up the outbound track just outside the station.

Metro is planning a more significant repair for the structure during what had been planned as a three-week shutdown of that area of the Red Line for track work beginning in October. 

The area was initially included in the major track work zone primarily due to the need for significant track repairs in the area, including an interlocking where trains move from one track to the other.

The exact timing of the work zone and at least some of the others remaining is expected to be announced in the next few weeks after plans are adjusted based on new federal safety recommendations and independent inspections.

In the case of the bridge at Rhode Island Avenue, Metro said in a statement Wednesday “the structure is safe for trains to use. However, Metro has put in place a temporary speed restriction in order to reduce stress on the structure and thereby lessen the rate of deterioration until permanent repairs can be made later this year.”

The speed restrictions are expected to add up to four minutes to Red Line trips toward Silver Spring and Glenmont, which could have somewhat of a ripple effect down the line.

Even after concrete repairs are made, the restrictions are expected to remain for “several weeks” while the concrete cures, Metro said.