Water samples were collected at two sites on the Cuyahoga River within the CVNP 4 days per week from June through August 2006. Old Portage, a site upstream from the southern boundary of the park, is an established USGS streamgage site (ID number 04206000). Real-time data for this site can be accessed at http://waterdata.usgs.gov/oh/nwis/nwisman/?site_no=04206000&agency_cd=USGS. Jaite, a site centrally located in the park, does not have an established gage on site, but previous studies in the park have provided streamflow data at the site. At both sites, sampling was done by use of a weighted bottle sampler lowered from a bridge. Water samples were collected using a sterile, 1-L bottle fitted into the sampler that was allowed to fill to within 2 in. of the top. Once the bottle and sampler were pulled back up to the bridge surface, the bottle was capped, removed from the sampler, and placed on ice in a cooler until analyses were performed. All analyses were performed by an NPS student employee who was trained specifically for this project.