Iowa isn’t well known as a trout fishing destination, and compared to neighboring states such as Minnesota and Wisconsin, she doesn’t have a large number of wild trout streams. However, as Spencer Tracy famously said about Katherine Hepburn, “What she does have is cherce!” The Driftless Area of the Northern Mississippi valley covers parts of NE Iowa, delivering high quality limestone waters. Extensive work to establish sustainable agricultural practices have improved water quality in many areas, and trout fishing is now better in most streams than in living memory.
The image below illustrates the range of data which is available for free download. At this scale, it’s a little hard to see, but streams are presented as colored squiggles. These are downloadable as KML/KMZ files suitable for use in Google Earth, Google Maps, the National Map, and other mapping software and web services, so you can use them at much larger scales.
Source: Iowa DNR, Google Earth
These sources include mapping data for Cold Water Streams, and Trout Streams designated by the DNR. Additional information about the different data sets and color coding is available in the download system.