1. San Francisco Estuary Institute Small Tributaries Loading Study Zone 4 Line A Sources Pathways and Loadings Workgroup May 6 th 2010 Rand Eads RiverMetrics LLC www.rivermetrics.com rivermetrics@gmail.com 503-435-7516 Item #3c Alicia Gilbreath SFEI

2. San Francisco Estuary Institute Item #3c

3. San Francisco Estuary Institute Item #3c Years sampled so far

4. Flow-Sediment Summary UnitsHY07HY08HY09HY10 Seasondays171132190189 Q peak > 50cfs1551228 Q peak > 100cfs52216 Q peak > 150cfs2117 Q totcfs44,56911,83161,29299,204 Q maxcfs224236165248 Turbidity maxNTU1041892437860 Rainfallin10.582.1111.7413.26 SSC samplescount84527480 SSC maxmg/L2,7441,050478NA SS loadkg84,96233,61443,726NA San Francisco Estuary Institute Item #3c

5. San Francisco Estuary Institute Item #3c

6. San Francisco Estuary Institute Item #3c

7. Flow -Turbidity - Sediment Characteristics Rapid response to rainfall Duration of hydrograph is short Poor relation between flow and sediment Phase and amplitude of flow and turbidity peaks often different Turbidity-SSC relation is good to excellent Storm-wise SSC loads slight improvement over annual loads Storms with multiple flow peaks often have declining turbidity peaks San Francisco Estuary Institute Item #3c

8. Sample Inventory Item #3c San Francisco Estuary Institute 2007200820092010 HgT40323035 HgD, MeHgT, MeHgD20161019 HgR910 PCBs20321618 PBDEs20858 OC Pesticides, PAHs788 Pyrethroids8 Se – T,D,(IV),(VI),Me10 Trace Elements211611 (Cu) Fe1610 SSC100 80 Nutrients12 DOC, POC161314

9. Item #3c HgT range (n=76*): 1.4 – 113 ng/L * only samples during times the turbidity was recorded are reported. San Francisco Estuary Institute

10. Item #3c t-PCB range (n=43*): 332 – 52,375 pg/L * only samples during times turbidity was recorded are reported.

11. Item #3c Rainfall data downloaded from Western Regional Climate Center (www.wrcc.dri.edu) San Francisco Estuary Institute

12. Item #3c Loads HgT (g) Cu (kg) t-PCBs (g) 2007 2009 Long-term Avg 2007 2009 Long-term Avg 2007 2009 Long-term Avg

13. San Francisco Estuary Institute Item #3c

14. San Francisco Estuary Institute Item #3c

15. Side-by-side Automated Hg Sampling San Francisco Estuary Institute Item #3c 3.3% 0.8% 11.6% 3.8% 54% RPD =

16. Automated PCB Sampling San Francisco Estuary Institute Item #3c 3.3% 0.8% 11.6% 3.8% 54% RPD =

17. What We Don’t Know Item #3c Upper end of discharge rating only 1 measurement above 135 cfs Low flow discharge & turbidity spikes unrelated to rainfall Contaminant-turbidity relationship at higher turbidity Not sampled a wet year with high intensity rainfall

18. Acknowledgements Item #3c Labs: MLML Axys Analytical Brooks Rand Romberg-Tiburon Center for Environmental Studies Site Access and Rainfall Data: Alameda County Flood Control and Water Conservation District

19. San Francisco Estuary Institute Item #3c Loads: Area-normalized

20. San Francisco Estuary Institute Item #3c FWMC