The USEPA participated in the 2015 Cooperative Science and Monitoring Initiative (CSMI) focus year for Lake Michigan. This work is describd here: http://www.iiseagrant.org/pdf/LakeMichiganCSMI2015FullReport.pdf As a small sub-component of this work EPA staff collected water quality data at the locations listed in grand_musk_tp.csv. The fields in grand_musk_tp.csv are described in grand_musk_tp.metadata.csv. This data was collected to support (provide validation data for) EPA nearshore nutrient modeling work described in the paper (in prep.) “Nearshore Nutrient Circulation in the Great Lakes - can a simple model provide transparency and utility?”.