Starting today, Cedar Rapids will being converting Second Avenue from one-way to two-way in downtown. This is one block east of Business 151. It’s going to take a while because the city is going to add “bump-outs” — things on corners that stop you from driving straight ahead from the parking area — and new railroad crossing signals have to be put in. Here is a city map (PDF) showing what streets are going to be converted the next couple of years, and which ones are staying one-way.
The Second and Third avenue bridges are going to have angle parking installed, with one lane of traffic in each direction. While Second and Third currently have three lanes of through traffic, addition of the bike lanes probably takes that down to one each way. All the stoplights along Second Avenue downtown are going to be taken out and replaced with four-way stops, too.