Aaron Weiner has a post about the complete lack of bike lanes in Ward 8.
I should add two caveats. First, these numbers don't include off-road bike trails, like Ward 8's Anacostia Riverwalk Trail, which offers some of the most pleasant biking in town. And second, DDOT doesn't list bike lanes on streets that form the border between two wards as belonging to either ward, and there are 0.59 miles of bike lanes listed separately as being shared by wards 7 and 8—presumably the lane on 25th Street SE and Naylor Road SE. Still, a caveat to that caveat: I've been listing the "grand totals" of bike lanes, which include not only dedicated lanes, but also shared lanes and bus/bike lanes. Looking only at proper bike lanes, the mileage shared by wards 7 and 8 is just 0.32 miles.
There may be some sharrowed lanes, but there is another caveat he leaves out.
The area EOTR was mostly developed after the car came along. This means that the roads were all designed to be the ideal width for car traffic.
Older streets in DC - like on Capitol Hill - were not and thus are not some multiple of 11 feet wide. This means that on Capitol Hill, once they put in auto lanes the road often has a little extra space left over. DDOT has been turning that extra space into bike lanes. On Capitol Hill, they turned a lot of wide one-way, one lane streets into normal one-way, one lane streets with a bike lane. They can't do that EOTR. EOTR, putting in bike lanes means taking out parking or taking out a traffic lane.
So that's the main reason why Ward 8 doesn't have bike lanes. Putting in bike lanes would be a massive fight.
But additionally, CM Barry is probably the least interested in biking. He's not opposed to it or anything, he just doesn't show a lot of interest. I've never seen him at Bike to Work day. He rarely fills his seat on the Bicycle Advisory Council. He doesn't go to oversight hearings or get involved. Every other CM does. So, they're hasn't been a lot of pressure on DDOT. Squeaky wheel gets the bike lanes.
Update: Also, the bike plan didn't include many bike lanes in Ward 8, so DDOT's doing what they planned to do.