Don't BLock Our Communities Act or the D-BLOC Act This bill prohibits railroad carriers from obstructing travel at public highway-rail crossings for more than 10 minutes, except under limited circumstances (e.g., safety issues). The Department of Transportation (DOT) must investigate and send notices to carriers of repeated incidents; carriers are subject to civil penalties for violations that occur after having received notice. Additionally, each Class I railroad carrier must publish on its home page an active link to the blocked highway-rail crossing portal that is maintained by the Federal Railroad Administration. The portal is used to (1) collect information from the public, including first responders, regarding blocked highway-rail grade crossing events; (2) solicit the apparent cause of the blocked crossing and provide examples of common causes of blocked crossings; (3) provide each complainant with the contact information for reporting a blocked crossing to the relevant railroad; and (4) encourage each complainant to report the blocked crossing to the relevant railroad.