At the fishery we've been able to get away with 300' of anchor rope. Fresh shad is best, you can catch them below bonneville. Fishing for sturgeon upstream of beacon rock closes during the spawning season, don't have the exact dates. I normally catch shad in the willamette, don't know exactly where's best on the columbia. This is hard water and you'll be using heavy lead to keep the shad on the bottom, hook out of the head and half hitches to the back of the body. Cut off the tail fin and operculum to reduce drag and keep bait on bottom. Bob is right, the guide boats will show you where's best, but don't be afraid to do a little exploring, as long as you stay outside the shipping channel.