1. Automated Continuous Streamflow and Water-Quality Monitoring in the Blackstone River at the Massachusetts-Rhode Island State Line U.S. Geological Survey New England Water Science Center in cooperation with Massachusetts Dept. of Environmental Protection Division of Watershed Management US Department of Interior US Geological Survey U.S. Department of the Interior U.S. Geological Survey

2. Blackstone River Basin Blackstone River at Millville, MA 01111230 DRAFT

3. Objectives: Monitor streamflow and water-quality at USGS station 01111230 (Blackstone River at Millville, MA) Collect data sufficient to produce reliable estimates of nutrient, suspended-sediment and trace-metal loads crossing the Massachusetts-Rhode Island state line Use surrogate water-quality indicators to develop equations to calculate real-time estimates of constituent loads Approach: Automated, composite sampling to provide a more accurate record of total loads and also variations in loads. DRAFT

4. USGS Station 01111230 Blackstone River at Millville, MA

5. Automated flow-proportional sampling with in-line filtration Refrigerator Logger, modem, and relay enclosure Pump and Filtration enclosure Heater Sampling and filtration pumps Filter bank for metal samples Flow switch Vented holding vessels Pinch valves Keypad and battery backup To refrigerated sample containers DRAFT

6. US Department of Interior US Geological Survey DRAFT

7. Manual EWI sampling from RR bridge for quality assurance of automated flow-proportional point samples DRAFT

8. US Department of Interior US Geological Survey Flow duration curve at Route 122 and manually sampled events at Millville sampled events Bridge/Point/Blank samples 04/16/14 flow: 1370 cfs Point sample 03/24/14 flow: 687 cfs Point sample 06/26/14 and 07/03/14 flows: 116 and 87 cfs Bridge/Point sample 06/19/14 flow: 172 cfs Bridge/Point sample 05/01/14 flow: 1250 cfs Provisional data pending final approval

9. 14-day nutrient loads, Blackstone River at Millville-October 2012 to November 2013 Provisional data pending final approval

10. US Department of Interior US Geological Survey Four-day metals loads, Blackstone River at Millville-October 2012 to November 2013 Provisional data pending final approval

11. Initial regressions on particulate metals and in situ turbidity US Department of Interior US Geological Survey Provisional data pending final approval

12. US Department of Interior US Geological Survey Conclusions: Continuous records and point samples collected in the Blackstone River at the MA-RI state line are representative of water-quality conditions in the river. Transport of nutrient and trace-metal species across the MA-RI state line can be monitored by automated, flow- proportional sampling. Continuous, real-time loads for nutrients, trace metals, and other constituents of interest may be estimated from surrogate records. Uncertainties associated with load estimates need to be confirmed. DRAFT