The last thing you want is a gritty chowder; trust me on this. So cleaning the steam clams is a must. 1. Inspect--Check the clams and toss any cracked or broken ones. If any are open, tap them gently. If they close, they're good to go. If they don't close, they're dead, so throw them out. 2. Soak--Place a colander in a large bowl and fill it with cold water. Add the clams, gently swish them around, then let soak for a few minutes. Lift the colander full of clams out of the bowl. Drain and refill the bowl. Repeat soaking, draining, and refilling until the water is clear and grit-less.