Prototype how to parse out #anchors in document url?

I'm trying to use effect.ScrollTo to automatically smooth scroll to the anchor in the location bar. I can't use onclick because the link calling the anchor is on another site.

How can I have prototype scrollto based on the url and not a link?

 

location.hash

Code (markup):

?

 

The browser will jump to the anchored div on load by default. I need a way to intercept that event and replace it with the smooth scrolling effect.