Wood and Water Doesn't Make a Good Seal

It's been a while again. I have new door on my side entrance. I have a new roof above my cellar entrance. Hopefully I'll show the details soon. Now, I'm working on getting windows installed. 

Last night, I tore out the old sill under one of the windows that will be installed soon. As you can see, It was very rotten. Keep in mind this was under the old cellar roof for a number of years. My plan is to cast custom concrete 4"x6" sills to fit right back in the same hole. More on that soon...hopefully.