Jason Krumholz Candace Oviatt Leslie Smith NEERS 4132012

Jason Krumholz, Candace Oviatt, Leslie Smith NEERS 4/13/2012

• • • Introduction and Background How have inputs to the Bay changed? How does this impact the standing stocks? Do we see changes in biology? What does it mean/Why do we care?

• 380 km 2 surface area. Watershed is ~ 4250 km 2 • Dominant circulation pattern is tidally driven • Watershed is home to 2 million people- very dense. • 65% of 2003 Nitrogen loading from sewage (Nixon et al. 2008) • Management intervention • (Brief) Survey Description

Lower Nutrients Less Chlorophyll Less Settling Organic Matter Less Benthic O 2 Demand Less Hypoxia

Average of annual average concentrations (2006 -2010)

• DIN/DIP ratio <16: 1 is traditionally viewed as a nitrogen limited system. • On an annual average basis, Narragansett Bay remains nitrogen limited throughout, though this limitation is more severe in the mid and lower bay. • On shorter time scales, some areas of the Upper Bay do show evidence of P limitation, which may become even more important as N inputs continue to drop. Average of annual average concentrations (2006 -2010)

700 Load (103 mol N/d) 50 Annual Sewage Nutrient Load 40 600 500 30 400 20 300 200 TN TP 100 0 2001 2002 2003 2004 2005 Year 2006 2007 2008 2009 10 Laod (103 mol P/d) 800 0 2010 Upgraded Non-Upgraded N Load (Kmol/d) 150 100 50 0 R 2 = 0. 0809 -50 2001 2002 2003 2004 2005 Year 2006 2007 2008 2009 2010

Standing Stock (10 6 Moles) 60 50 79 -80 yearly average 06 -10 yearly average 79 -80 summer average 06 -10 summer average *= P<0. 05 **= P<0. 01 40 30 20 ** * 10 * ** ** 0 DIN PO 4 Si. O 4 TN TP *

Chlorophyll-a (mg/L) 40 R 2 = 0. 1178 30 20 10 0 1975 7 Chlorophyll-a (mg/L) Annual Maxiumum Chlorophyll-a 1980 1985 1990 1995 2000 2005 2010 Annual Average Chlorophyll-a 6 5 4 3 2 1 0 1975 1980 1985

• Recent management efforts to reduce nitrogen loading have resulted in an approximately 1: 1 reduction in standing stock. • Phosphorus loads are already 30 -50% less than peak levels. – WWTF & non-point sources – May become more important to biology, especially in upper bay. • At present, no or minimal biological response to the loading reductions can be detected. • Future reductions may be large enough to elicit some biological response Adapted from Oviatt et al. 1986

Rossie Ennis Leslie Smith Scott Nixon Angelo Liberti Steve Granger Ashley Bertrand Catherine Walker Brooke Longval Christine Comeau Danielle Dionne Jamie Vaudrey Conor Mc. Manus Chris Melrose & NOAA/DEM Shuttle Team Funding Support: NOAA CHRP - Libby Jewett & Alan Lewitus, Project Officers NOAA Bay Window – Sarah Pike, Project Officer References Oviatt, C. (1980). Some aspects of water quality in and pollution sources to the Providence River. In R. Pastore, Report for Region 1 EPA. September 1979 -September 1980. Boston, MA: United States Environmental Protection Agency. Oviatt, C. , Keller, A. , & Reed, L. (2002) Annual primary production in Narragansett Bay with no bay-wide winter-spring phytoplankton bloom. Estuarine Coastal and Shelf Science, 54, 1013 -1026. Nixon, S. W. , Buckley, B. A. , Granger, S. L. , Harris, L. A. , Oczkowski, A. J. , Fulweiler, R. W. , & Cole, L. W. (2008). Nitrogen and Phosphorus Inputs to Narragansett Bay: Past, Present, and Future. In B. Costa-Pierce, & A. Desbonnet, Science for Ecosystem -based Management (pp. 101 -175). New York: Springer. Kremer, J. N. , J. M. P. Vaudrey, D. S. Ullman, D. L. Bergondo, N. La. Sota, C. Kincaid, D. L. Codiga, and M. J. Brush. 2010. Simulating property exchange in estuarine ecosystem models at ecologically appropriate scales. Ecological Modelling 221: 1080 -1088.

NET EXPORT 451 NET EXPORT 283

% Ammonium in DIN 70 2006 -2010 60 1979 -1980 50 R 2 = 0. 93 P>0. 001 40 30 20 10 0 0 10 20 30 Distance from Fields Point (km) 40 50

Phase 1: Operational 11/2008 Phase 2: 2009 -2013 Phase 3: 2015 -2021

General Form: Nd=N 0 e-kd 100 Modeled PO 4 1: 1 Modeled PO 4 (m. M) Modeled DIN R 2 = 0. 71 80 60 40 20 0 0 20 40 60 Observed DIN (m. M) 10 R 2 = 0. 78 8 6 4 2 0 80 0 2 1200 1000 800 600 400 200 0 10 20 30 Distance from Fields Point (km) 4 6 Observed PO 4 (m. M) 8 10 PO 4 residuals by distance Squared Residual DIN residuals by distance 0 1: 1 40 20 15 10 5 0 0 10 20 30 Distance from Fields Point (km) 40

14 12 10 8 6 4 2 0 2006 -2009 1979 -1980 0 5 10 15 20 25 30 distance from Fields Point (km) 35 40 45 50 Upper Bay Seasonal N/P Ratio DIN/DIP ratio Annual Average Downbay N/P ratio 2006 -2009 40 35 30 25 20 15 10 5 0 1979 -1980 Redfield 0 2 4 6 Month 8 10 12

Sound to Bay Phosphate flux 2006 25000 Moles/day 20000 15000 10000 Series 1 5000 0 0 50 100 150 Julian Day 2006 200 250 300

5 ln of concentration (m. M) 4 06 -09 Annual average TN 97 -98 Annual average TN 06 -09 annual average DIN 79 -80 annual average DIN 06 -09 annual average PO 4 79 -80 annual average PO 4 3 Intercept: NS Slope: NS 2 1 Intercept: NS Slope: P= 0. 008 0 -1 Intercept: P=0. 005 Slope: NS 0 10 20 30 distance from Fields Point (km) 40 50

Discharges to: Narragansett Bay Field's Point Bucklin Point Newport East Providence Bristol Warren East Greenwich a Quonset Point Jamestown Fall River* Blackstone River Worcester b Woonsocket Smithfield a Grafton* Millbury* Northbridge* Burrillville Hopedale* Leicester* Douglas* Upton* Ten Mile River Attleboro North Attleboro c Pawtuxet River Cranston a West Warwick Taunton River Brockton* Taunton* Somerset* Flow Mean 1. 7 x 105 8. 5 x 104 3. 5 x 104 2. 7 x 104 1. 4 x 104 7. 1 x 103 4. 1 x 103 1. 8 x 103 DIN St Dev 4. 2 x 104 2. 7 x 104 1. 1 x 104 8. 1 x 103 5. 1 x 103 2. 8 x 103 8. 5 x 102 4. 7 x 102 TN Mean 4. 6 x 107 1. 5 x 107 St Dev 7. 6 x 106 3. 3 x 106 6. 7 x 106 3. 9 x 106 1. 6 x 106 1. 3 x 106 1. 8 x 106 5. 2 x 105 1. 8 x 104 7. 2 x 104 1. 5 x 105 9. 5 x 102 DIP d TP Mean 6. 2 x 107 1. 9 x 107 1. 1 x 107 7. 6 x 106 6. 1 x 106 1. 9 x 106 8. 7 x 105 7. 3 x 105 1. 6 x 105 St Dev 9. 1 x 106 3. 1 x 106 2. 3 x 105 6. 0 x 105 1. 5 x 106 2. 5 x 104 4. 3 x 104 2. 2 x 103 1. 4 x 103 Mean 1. 5 x 106 2. 4 x 106 4. 0 x 105 4. 5 x 105 1. 2 x 105 3. 6 x 104 2. 9 x 105 6. 8 x 104 1. 7 x 104 St Dev 9. 1 x 104 2. 7 x 105 2. 8 x 102 9. 1 x 101 2. 1 x 101 1. 2 x 101 5. 8 x 10 -1 9. 3 x 10 -1 1. 9 x 100 Mean 3. 0 x 106 3. 1 x 106 5. 9 x 105 5. 2 x 105 1. 8 x 105 5. 2 x 104 4. 2 x 105 1. 0 x 105 2. 5 x 104 St Dev 5. 2 x 105 9. 1 x 105 1. 3 x 104 6. 8 x 103 2. 0 x 103 8. 0 x 102 4. 9 x 102 3. 0 x 102 2. 2 x 102 1. 5 x 106 1. 3 x 105 3. 3 x 105 4. 8 x 105 3. 4 x 105 1. 4 x 104 1. 6 x 102 7. 1 x 105 5. 0 x 105 2. 1 x 104 2. 5 x 105 1. 8 x 103 1. 1 x 105 2. 9 x 104 7. 6 x 103 4. 2 x 104 8. 9 x 103 1. 9 x 103 4. 5 x 106 1. 2 x 106 1. 3 x 106 2. 4 x 105 1. 7 x 107 5. 4 x 106 1. 5 x 106 3. 2 x 103 8. 4 x 102 1. 3 x 106 1. 2 x 105 1. 4 x 106 1. 2 x 105 1. 6 x 104 1. 3 x 102 2. 4 x 104 1. 8 x 103 1. 5 x 104 1. 6 x 104 4. 3 x 103 4. 4 x 103 7. 6 x 106 3. 0 x 106 4. 5 x 105 7. 8 x 105 1. 9 x 104 2. 1 x 104 1. 6 x 104 7. 0 x 103 2. 8 x 104 3. 0 x 104 2. 1 x 104 1. 5 x 104 4. 3 x 104 2. 3 x 104 1. 9 x 104 1. 0 x 104 6. 3 x 103 2. 0 x 103 1. 3 x 107 8. 2 x 106 4. 7 x 106 2. 4 x 106 1. 7 x 106 1. 0 x 106 2. 9 x 105 3. 0 x 105 1. 3 x 105 5. 0 x 103 2. 4 x 104 8. 0 x 104 4. 3 x 105 4. 4 x 105 2. 0 x 105 4. 6 x 104 1. 0 x 105 1. 3 x 105 1. 0 x 107 6. 9 x 106 3. 8 x 106 2. 4 x 106 1. 8 x 106 9. 4 x 105 * indicates facilities that do not have annual data. a Average and standard deviation values are for 2007 -2010 to avoid averaging over upgrade completion. b Average nitrogen and phosphorus load values are 2010 load values as this is the only year of data available after upgrades were completed. c Average and standard deviation values are for 2009 -2010 to avoid averaging over upgrade completion. d Average DIP load values for the Field’s Point, Bucklin Point, and East Providence facilities were calculated using the ratio between DIP and TP values from earlier measurements (Nixon, et al. , 1995). The ratio between DIP and TP for the remaining facilities was calculated by taking the average of the DIP to TP ratios of the Field’s Point, Bucklin Point, and East Providence facilities. Average DIP load values for the remaining facilities were calculated using this average ratio.

Flow DIN TN DIP TP Mean St Dev Mean St Dev Blackstone River a 2. 574 2. 874 66. 821 18. 452 89. 185 40. 222 2. 341 0. 744 5. 758 1. 641 Pawtuxet River 1. 071 1. 366 29. 047 6. 333 41. 413 10. 272 0. 923 0. 199 1. 949 0. 943 Woonasquatucket River 0. 225 0. 266 3. 744 0. 603 5. 526 1. 094 0. 052 0. 058 0. 172 0. 069 Moshassuck River 0. 115 0. 163 1. 877 0. 310 2. 612 0. 241 0. 006 0. 001 0. 014 0. 002 Ten Mile River 0. 320 0. 333 10. 780 2. 226 14. 087 1. 922 0. 095 0. 024 0. 028 0. 000 Taunton River 1. 502 1. 516 45. 340 13. 191 81. 273 22. 824 0. 804 0. 168 1. 290

Discharges to: Narragansett Bay Field's Point Bucklin Point Newport East Providence Bristol Warren East Greenwich a Quonset Point Jamestown Fall River* Blackstone River Worcester b Woonsocket Smithfield a Grafton* Millbury* Northbridge* Burrillville Hopedale* Leicester* Douglas* Upton* Ten Mile River Attleboro North Attleboro c Pawtuxet River Cranston a West Warwick Taunton River Brockton* Taunton* Somerset* Flow Mean 1. 7 x 105 8. 5 x 104 3. 5 x 104 2. 7 x 104 1. 4 x 104 7. 1 x 103 4. 1 x 103 1. 8 x 103 DIN St Dev 4. 2 x 104 2. 7 x 104 1. 1 x 104 8. 1 x 103 5. 1 x 103 2. 8 x 103 8. 5 x 102 4. 7 x 102 TN Mean 4. 6 x 107 1. 5 x 107 St Dev 7. 6 x 106 3. 3 x 106 6. 7 x 106 3. 9 x 106 1. 6 x 106 1. 3 x 106 1. 8 x 106 5. 2 x 105 1. 8 x 104 7. 2 x 104 1. 5 x 105 9. 5 x 102 DIP d TP Mean 6. 2 x 107 1. 9 x 107 1. 1 x 107 7. 6 x 106 6. 1 x 106 1. 9 x 106 8. 7 x 105 7. 3 x 105 1. 6 x 105 St Dev 9. 1 x 106 3. 1 x 106 2. 3 x 105 6. 0 x 105 1. 5 x 106 2. 5 x 104 4. 3 x 104 2. 2 x 103 1. 4 x 103 Mean 1. 5 x 106 2. 4 x 106 4. 0 x 105 4. 5 x 105 1. 2 x 105 3. 6 x 104 2. 9 x 105 6. 8 x 104 1. 7 x 104 St Dev 9. 1 x 104 2. 7 x 105 2. 8 x 102 9. 1 x 101 2. 1 x 101 1. 2 x 101 5. 8 x 10 -1 9. 3 x 10 -1 1. 9 x 100 Mean 3. 0 x 106 3. 1 x 106 5. 9 x 105 5. 2 x 105 1. 8 x 105 5. 2 x 104 4. 2 x 105 1. 0 x 105 2. 5 x 104 St Dev 5. 2 x 105 9. 1 x 105 1. 3 x 104 6. 8 x 103 2. 0 x 103 8. 0 x 102 4. 9 x 102 3. 0 x 102 2. 2 x 102 1. 5 x 106 1. 3 x 105 3. 3 x 105 4. 8 x 105 3. 4 x 105 1. 4 x 104 1. 6 x 102 7. 1 x 105 5. 0 x 105 2. 1 x 104 2. 5 x 105 1. 8 x 103 1. 1 x 105 2. 9 x 104 7. 6 x 103 4. 2 x 104 8. 9 x 103 1. 9 x 103 4. 5 x 106 1. 2 x 106 1. 3 x 106 2. 4 x 105 1. 7 x 107 5. 4 x 106 1. 5 x 106 3. 2 x 103 8. 4 x 102 1. 3 x 106 1. 2 x 105 1. 4 x 106 1. 2 x 105 1. 6 x 104 1. 3 x 102 2. 4 x 104 1. 8 x 103 1. 5 x 104 1. 6 x 104 4. 3 x 103 4. 4 x 103 7. 6 x 106 3. 0 x 106 4. 5 x 105 7. 8 x 105 1. 9 x 104 2. 1 x 104 1. 6 x 104 7. 0 x 103 2. 8 x 104 3. 0 x 104 2. 1 x 104 1. 5 x 104 4. 3 x 104 2. 3 x 104 1. 9 x 104 1. 0 x 104 6. 3 x 103 2. 0 x 103 1. 3 x 107 8. 2 x 106 4. 7 x 106 2. 4 x 106 1. 7 x 106 1. 0 x 106 2. 9 x 105 3. 0 x 105 1. 3 x 105 5. 0 x 103 2. 4 x 104 8. 0 x 104 4. 3 x 105 4. 4 x 105 2. 0 x 105 4. 6 x 104 1. 0 x 105 1. 3 x 105 1. 0 x 107 6. 9 x 106 3. 8 x 106 2. 4 x 106 1. 8 x 106 9. 4 x 105 * indicates facilities that do not have annual data. a Average and standard deviation values are for 2007 -2010 to avoid averaging over upgrade completion. b Average nitrogen and phosphorus load values are 2010 load values as this is the only year of data available after upgrades were completed. c Average and standard deviation values are for 2009 -2010 to avoid averaging over upgrade completion. d Average DIP load values for the Field’s Point, Bucklin Point, and East Providence facilities were calculated using the ratio between DIP and TP values from earlier measurements (Nixon, et al. , 1995). The ratio between DIP and TP for the remaining facilities was calculated by taking the average of the DIP to TP ratios of the Field’s Point, Bucklin Point, and East Providence facilities. Average DIP load values for the remaining facilities were calculated using this average ratio.

Flow DIN TN DIP TP Mean St Dev Mean St Dev Blackstone River a 2. 574 2. 874 66. 821 18. 452 89. 185 40. 222 2. 341 0. 744 5. 758 1. 641 Pawtuxet River 1. 071 1. 366 29. 047 6. 333 41. 413 10. 272 0. 923 0. 199 1. 949 0. 943 Woonasquatucket River 0. 225 0. 266 3. 744 0. 603 5. 526 1. 094 0. 052 0. 058 0. 172 0. 069 Moshassuck River 0. 115 0. 163 1. 877 0. 310 2. 612 0. 241 0. 006 0. 001 0. 014 0. 002 Ten Mile River 0. 320 0. 333 10. 780 2. 226 14. 087 1. 922 0. 095 0. 024 0. 028 0. 000 Taunton River 1. 502 1. 516 45. 340 13. 191 81. 273 22. 824 0. 804 0. 168 1. 290

Sound to Bay Phosphate flux 2006 25000 Moles/day 20000 15000 10000 5000 0 0 50 100 150 Julian Day 2006 200 250 300