Baltimore’s efforts to affordably control traffic and promote resident safety have hit a bump in the road due to a shortage of poles, a basic component for the installation of stop signs, speed hump alerts and other street markers. The severity of Baltimore’s pole shortage, and how exactly supplies got so low, isn’t clear. Councilman Mark Conway said the shortage has delayed stop sign and speed hump installations in his district. And at one point earlier this year, the city was out of poles completely, according to Councilman Ryan Dorsey, who said a transportation staff member informed him months ago that the department had ordered too few poles.