Searay, you can check out this site from the NH DES
http://www.des.state.nh.us/Beaches/current.asp
Even though you would think the lake is getting a wash out with heavy rains in and the dam open, it's not the way the bacteria counts work. I have worked for the MA state park system for a number of years and supervised four public beaches. Besides the resident Canada Geese population that exaceberated the bacteria counts, usually after a heavy rainstorm water samples would be high bacteria. What accounts for this is the natural leaching of the water over a vast amount of the watershed. Which means that the water droplets move over a variety of geographical features including septic systems, stormwater drains that collect stuff off the roads and parking lots and in areas that can carry fecal matter of wildlife and pets and livestock into the water either directly or indirectly (called non-point pollution). Good luck to your wife in the Timberman