Working with styrofoam

[Trackman Ed]

Alright all you experienced HO scale owners, I need some ideas on how to sculpt (cut, shape, what ever you call it) 1 inch styrofoam.  I have my pond and the creek that leads to it masked out and I've begun some of the greenery nearby.  My only holdup (frustration) is turning the masked area into a water like environment.  I am using Woodland Scenic's "Realistic Water" product.  The Woodland Scenics recommends 1/8" thickness when poured.  To achieve the 1/8" I must then do something with the styrofoam. 

I have watched many hours of videos from various web sites including Woodland Scenics.  What I need is some insight on how to remove some styrofoam from my planned area to get the 1/8" depth.  I need experienced ideas, ideas that a newcomer to the hobby can use with some certainty of good results

 

[electrical whiz kid]

The one thing I will tell you is to make doubly sure that the area intended is sealed off to prevent run-off.  I haven't had it happen personally, but I know several guys it happened to.  You will learn new words if you don't.
Also, there are a lot of different observations from guys like Dave Frary, George Sellios, Woodland Scenics, et al.
On Styrofoam sculpting, try to go to "you tube" and you will find a good amount of instructional data.
SGT C. 

[Jerrys HO]

Ed how big of an area? I used a bondo grater( http://www.repaintsupply.com/stanley-21-299a-surform-10-half-round-cheese-grater-blade-p3691.html?utm_source=google-shopping&utm_medium=organic) to sculpt mine and sanded smooth. I also used WS flex paste to seal the whole thing. The flex paste is sandable after curing and paintable.
The depth cutting was not an issue, the painting is/was. You can always add material to get your depth right or just add a little more water.

[AGSB]

Instead of digging out the styrofoam for a pond you could always build up the area around the pond. That way you can get more variation on the shore line.