What plant is this?

I found this growing in mud along the Columbia River near Portland, OR today. The plant is about a foot tall with 1, 2 or 3 stalks. At the top of each stalk is one distinctive looking leaf. I picked one and scanned it in (it's a little worse for wear from being in my pocket). I sized the scan so it's life size, on my monitor at least.

 

Sagittaria may be?

 

Thanks, I looked it up and it sure looks like it.