The resources on the web, that are available pertaining to watersheds, are great.  Here is a list of sites that are especially interesting to folks working on watershed issues in Montana.  The federal and state agencies have done an excellent job making this information readily available to the public.  The sites listed here are excellent resources for maps and general information, as well as more specific regulatory information on certain watersheds.  Some sites that hold especially relevant information to the Ashley Creek Watershed are listed here:

DEQ Surf Your Watershed.
The TMDL schedule related to the Ashley Creek watershed is available here, as well as information on the 303d (impaired stream) status of Ashley Creek.
Go directly to the 303d report for Ashley Creek
Go directly to 303d summary for the state

Natural Resource Information System
This site was created by the state of Montana as a resource for natural resource information.  Access to maps and associated GIS data is available through this site.