From the research I have done for my personal business spring is going to be weird next year. The highest HS spring break for the areas I checked, (AL, TN, GA, IN, OH, MS, MO.. ETC) was April 2. March 25 week was also high. April 8 was fair, March 18 was fair, and March 12 was the high college week. Thats per my personal research for my business, which does not have as broad of a range as UO. I say weird because usually April 8 starts what we call "Crap weeks." Next year it's looking like it'll still be a decent week.
If you stay on site you will have the least impact of the crowds as you will get an express pass. Or you can purchase it. I recommend that for people who are traveling and have no idea how the crowds are going to be. Take a look at the power pass black out dates- those are usually when they're expecting higher crowd volumes. Mardi Gras concerts also have a very high impact on the weekends. Depending on who's playing you could have a VERY large crowd Saturday. That will not be posted for a very long time though.
