The city is undertaking what they call the Rock Creek East II Livability Study, which focuses on transportation issues in Petworth, Crestwood, Brightwood and 16th Street Heights, plus anything north of Spring Road and Rock Creek Church Road (which I'd argue isn't quite Petworth, but that's another topic.)
And there's a number of ways to give feedback: there's a quick online survey, public meetings to give your opinion, and a cool interactive map where you can mark where issues are. (The map doesn't seem to work on Safari, though.)
Here's the full description, from their website -- and on the survey you can choose what are the three priorities for you.
As a reminder, the purpose of this study is to identify opportunities for safer travel for residents and visitors to the neighborhoods of Petworth, Crestwood, Brightwood Park, and 16th Street Heights. The goals of the study are to enhance the community quality of life through improvements to transportation safety, connections to destinations, green infrastructure, and sustainability.And there are two events where you can give feedback: Thursday at the the Georgia Ave-Petworth Metro from 4:30-6:30 pm and on Saturday, May 14 at the 14th and Kennedy Farmers Market from 9am-1pm.