There is a country Store not far from the Dam that has minnows , shiners , night crawlers , etc. It is a BP. From the Dam just head towards Jamestown. It is about 5 miles roughly on the right. You cannot miss it.
And I bet you can plan on plenty of water from the Dam. They have been running 5 generators and 4 sluice gates. I have not heard of anyone doing much good in a boat when they are generating so much !
Good Luck, And post on the trip and let us know how it goes.