Commuters will start to experience the biggest impact of the New York Avenue Bridge reconstruction in late April. At that point, the lane capacity between Penn Street NE and Florida Avenue NE — an area traversed by thousands of drivers during the morning and afternoon rushes — will be reduced by a third to make more room for the rebuilding over the next two years.

D.C. Mayor Vincent C. Gray issued a warning to travelers this morning about the long-term impact of taking away two lanes on a six-lane commuter route. In a prepared statement, he said:

“There’s no other way to do it — this aging structure needs to be replaced for the safety of everyone who crosses it and for the rail traffic underneath. But I don’t want to understate the impact of taking away two lanes: there will be backups and it will take you significantly longer to get down New York Avenue until this project is completed.”

The D.C. Department of Transportation, which is in charge of the project, estimates that rush-hour travelers should anticipate delays of 15 to 30 minutes in the work area for the duration of the lane reductions.

The transportation department has been working in various places along New York Avenue NE for the past several years. The most notable projects besides the reconstruction of this bridge north of Union Station are the now-completed reconstruction of the New York Avenue-Florida Avenue triangle, where the Wendy’s restaurant is, and the still-unfinished replacement of the Ninth Street NE Bridge over New York Avenue.

Knowing that this high-impact phase was coming, the department has set up several programs to help travelers get around or through the area where the lanes shrink.

Bridge Bucks

This commuter incentive program also was used during the summertime closing of the Frederick Douglass (South Capitol Street) Bridge several years ago. In the new version, the first 2,000 commuters accepted into the program will receive a monthly incentive of $50 for their SmarTrip cards or other fare payment systems. The incentive can be used to pay for commuting alternatives that include trains, buses and vanpools — any transportation alternative that reduces the number of solo drivers on New York Avenue.

Applications are being accepted now through the project’s Web site at

Live traffic updates

Look for the variable message boards on the approaches to the New York Avenue corridor. The transportation department says they will be updated constantly to reflect current traffic conditions in the work zone. (This is unusual. We’re used to seeing boards with preset messages. Help us monitor the accuracy of the information on the boards.)

Tweets about the project

Travelers signed up to the project’s Twitter account at @NYAve411 will get construction alerts and traffic updates. For everyone’s safety, please check text messages before getting in the car, or have a passenger do it.

Alternative routes

Here’s the department’s list of alternatives for drivers who normally use the New York Avenue corridor. Let us know if you think the list should be expanded, or if you have questions about these options.

* Montana Avenue to Rhode Island Avenue to North Capitol Street

* West Virginia Avenue to Florida Avenue

* South Dakota Avenue to Rhode Island Avenue to North Capitol Street

* I-295 to two potential exits: Benning Road or East Capitol Street