Can you fish the Blue river from the park banks? Irwin Park I mean.

Yes and fishing license are required

In indiana you have to purchase a fishing license for age 16 and over for any public waters. One csn be purchased st the corner of 252 and eisenheier at the bait shop, or other known retailers

I have seen many people fishing from the bank there. I believe here in Indiana 17 and under can fish w no license.

I believe so but I would recommend calling them to be positive and I do know fishing license is necessary unless I think under 16. I may be wrong on age.