Try the following for races...<br>
setupevents.com<br>
tricolumbia.org<br>
piranha-sports.com<br>
restontriathlon.org<br>
runwashington.com<br><br>
Unfortunately, lots are already full for this year.<br><br>
Try the following for clubs...<br>
trirats.net<br>
tricats.org<br><br>
Not a whole lot of open water swimming opportunities nearby, but there's always the bay, some further away lakes and lots of pools. I use the W&OD Trail for most of my biking/running, but then I'm out past Dulles.