A map of the area of the Irving Dam in Irving, Michigan on the Thornapple River. The Irving dam is actually three different structures, which are labeled on the map as follows:

P - The powerhouse
O - The old flow control structure
S - the new flow control structure
This map is modified from a
USGS/USCB  TIGER generated map - link to original map

This TerraServer-USA topographical map shows the area clearly as well. Google maps are lacking in detail in this area.
Original PNG version (Image:Thornapple_TIGER_Irving_dam_area_map3c.PNG) generated by User:Lar (w:en:User:Lar) using the US Government provided TIGER tool. This map was then redrawn as an SVG by Amada44 and reuploaded.