A bit of good news for Dulles Toll Road users who’ve had to endure five straight years of rate hikes — the Metropolitan Washington Airports Authority, which manages and operates the toll road, will be giving away preloaded E-Z Pass transponders as part of a birthday celebration.

Next month, the Dulles Toll Road will be 30, and to celebrate the occasion, MWAA is hosting a drawing for 30 E-Z Pass transponders, preloaded with $15 in toll credits. Winners of the Oct. 1 drawing who register their transponder online will get an additional $20 in toll credits.

Current E-ZPass customers won’t be left out — they’ll  be entered in a bonus drawing for a $30 credit to their accounts.

MWAA has been doing its best to nudge toll road users to use the E-Z Pass. Moving to a system of  all-electronic toll collection would reduce costs for the authority and, they say, help ease congestion on the 16-mile toll road since drivers would not longer have to stop at gates to pay their tolls.

The extra dollars would no doubt come in handy, particularly for folks who’ve been less than pleased that they’ve been saddled with paying the bulk of the costs of the Silver Line rail project. The first phase of the $5.6 billion project opened July 26 with four stops in Tysons Corner and one in Reston at Wiehle Avenue. Work on the rail line’s second phase, which will include a stop at Dulles International Airport, is underway.