Several water quality monitoring networks exist within Indiana that are sampled to satisfy the water management needs of the organization conducting the sampling. For this paper, a total of 13 agencies or groups are identified that sample at least quarterly for multiple classes of chemicals, including nutrients, pesticides, and suspended solids or sediment. Sites that are sampled only for E. coli are not included in these networks. These 13 groups include the Indiana Department of Environmental Management (IDEM), the U.S. Geological Survey’s (USGS) National Water Quality Assessment (NAWQA) Program and National Stream Quality Accounting (NASQAN) networks, the U.S Department of Agriculture (USDA) Agricultural Research Service (ARS), the Ohio River Valley Water Sanitation Commission (ORSANCO), the cities of Indianapolis, Muncie, and Elkhart, several universities—Purdue University, Indiana University Purdue University Indianapolis (IUPUI), Manchester University, and Notre Dame University, the Marion County Public Health Department, and the St. Joseph River Watershed Initiative. All of these sites as well as active USGS streamflow gaging stations are identified in figure 1. A total of 300 sampling sites are included in these networks (Appendix 1). The intent is to add other agencies and groups to this document as they are identified.
Figure 1. Location of existing water quality networks and USGS streamflow gages in Indiana.
Each of the agencies/groups described below have different reasons for continued monitoring over time. The reason for the monitoring influences how long they have monitored, what they monitor, and when they monitor. Below is a description of the monitoring for each of the 13 agencies/groups shown in Fig. 1 and appendix 1.