AnnArbor.Crowdmap.com is an online system which has been collecting storm reports from the May 2011 flooding in Ann Arbor, as well as having in it previous information from past flood events and other incidents in Ann Arbor where there was widespread problems.
Crowdmap is a tool that allows you to crowdsource information and visualize it on a map and timeline.
I've typed in a bunch of these, but if you notice a news report of flooding, sewer spills, landslides, closed roads or fish flopping around on the road please add in a dot on the map with a link.
The image shows storm-to-date stormwater related incidents in Ann Arbor and the surrounding area – I will leave it to the world to decide how far away "surrounding" is, but certainly the Huron River watershed is in scope, and I suspect that the area to watch is roughly the size of the Arborwiki catchment basin.
More about Crowdmap at Tech Cocktail. A 2009 Business Insider story covers eBay founder Pierre Omidyar's investment in Ushahidi, the system that Crowdmap was built out of.