Loading of Phosphorus and Sediment to the South End of Cayuga Lake LOADEST Estimates Based on CSI-Volunteer Synoptic Sampling Partnerships, 2002-2013 Tompkins County Water Resources Council April 21, 2014

Cayuga Lake Watershed: CSI Monitoring Sites

Synoptic Sampling of Streams, From Mouth to Headwaters Volunteer groups monitor tributary streams in southern Cayuga Lake watershed “Monitor” means that groups perform synoptic sampling several times per year at fixed locations along a stream’s entire length CSI’s lab performs certified analyses of synoptic samples for phosphorus, sediment and other water quality parameters Results are posted on CSI’s website and may be searched and downloaded free of charg

Combine Synoptic Monitoring Results with USGS Flow Measurements Load = Concentration x Flow = mg/L x L/sec Transform units to get load in tons/year Concentrations come from synoptic monitoring Flows come from USGS gauging stations Flows estimated in absence of gauging station LOADEST Calculations by Dr. Matthew Yarrow

Simple step-by-step description of LOADEST Load Estimation Methodology More Info 1 Download Phosphorus concentration data from CSI Website Website 2 Download daily average and instantaneous flow data from USGS website 3 Download Latest LOADEST version (2013) and documentation 4 Calculate watershed area at CSI monitoring location - StreamStats 5 Estimate flows at CSI monitoring site using watershed are ratio method   6 Create Calib file for each analyte (SRP and TP) including instantaneaous flow estimations and CSI concentration data TP_Calib!A1 7 Create Est file using daily average flow data 8 Run LOADEST for Model 1 and using model auto-select option 9 Select model with best model fit stats for a given analyte and watershed Model Fit'!A1 10 Obtain load results from LOADEST for each parameter for selected model Load_Results!A1 11 Sum loads over water years to get final yearly load numbers Yearly Totals'!A1 12 Optional step: determine days with significant stormwater flow in order to estimate loads occurning during stormwater events versus days with base flow. Online baseflow separation tool LOADEST Documentation Runkel, R.L., Crawford, C.G., and Cohn, T.A., 2004, Load Estimator (LOADEST): A FORTRAN Program for Estimating Constituent Loads in Streams and Rivers: U.S. Geological Survey Techniques and Methods Book 4, Chapter A5, 69 p.

Sediment Loading To Fall-Virgil Creek TSS Loads (tons/yr) 2009 2010 2011 2012 2013 Davis Road Bridge 558 500 1502 409 733 Virgil Creek Freeville 1736 1686 6090 1083 2598 Fall Creek Freeville 1340 1220 3816 954 1807 Freese Road Bridge 7834 8435 35432 4118 13774 Cayuga Street Bridge 10946 10882 40862 6562 16996

Total Phosphorus Loading to Fall-Virgil Creek TP Loads (tons/yr) 2009 2010 2011 2012 2013 Davis Road Bridge 2.86 2.49 6.10 2.37 3.48 Virgil Creek Freeville 2.95 2.59 7.02 2.32 3.72 Fall Creek Freeville 4.03 3.52 8.89 3.30 4.96 Freese Road Bridge 12.28 10.80 29.22 9.66 15.46 Cayuga Street Bridge 15.06 13.40 38.49 11.41 19.45

Soluble Reactive Phosphorus Loading to Fall-Virgil Creek SRP Loads (tons/yr) 2009 2010 2011 2012 2013 Davis Road Bridge 1.46 1.27 2.95 1.24 1.75 Virgil Creek Freeville 0.92 0.80 1.87 0.78 1.11 Fall Creek Freeville 1.78 1.55 3.62 1.51 2.14 Freese Road Bridge 3.53 3.07 6.65 3.09 4.18 Cayuga Street Bridge 3.24 2.82 6.34 2.80 3.87

Sediment (TSS) Loading from Major Tributaries to Cayuga Lake (tons/year) 2011 2012 2013 Average Fall Creek Mouth 40,862 6,562 16,996 21,473 Six Mile Creek Mouth 30,241 3,202 4,343 12,595 Cayuga Inlet Mouth 43,388 8,366 8,475 20,076 CI – Farmers Market 51,933 7,642 8,191 22,589 Cascadilla Creek Mouth 2,240 633 615 1,163

Total Phosphorus Loading from Major Tributaries to Cayuga Lake (tons/year) 2011 2012 2013 Average Fall Creek Mouth 38.49 11.41 19.45 23.11 Six Mile Creek Mouth 17.56 4.57 4.55 8.89 Cayuga Inlet Mouth 45.26 13.42 12.61 23.76 CI – Farmers Market 45.80 11.91 11.40 23.04 Cascadilla Creek Mouth 3.88 1.74 1.56 2.39

Soluble Reactive Phosphorus Loading from Major Tributaries to Cayuga Lake (tons/year) 2011 2012 2013 Average Fall Creek Mouth 6.34 2.80 3.87 4.34 Six Mile Creek Mouth 2.12 0.99 0.89 1.33 Cayuga Inlet Mouth 5.18 2.21 2.02 3.14 CI – Farmers Market 4.84 2.10 1.92 2.95 Cascadilla Creek Mouth 1.26 0.60 0.54 0.80

Comparisons of Average Loads for Sediment (TSS), Total Phosphorus and Soluble Reactive Phosphorus 2011-2013 Average TSS Load (tons/yr.) 2011-2013 Average TP Load (tons/yr.) 2011-2013 Average SRP Load TP/TSS x 1,000 SRP/ TP Fall Creek Mouth 21,473 23.11 4.34 1.07 0.19 Six Mile Creek Mouth 12,595 8.89 1.33 0.71 0.15 Cayuga Inlet Mouth 20,076 23.76 3.14 1.18 0.13 CI – Farmers Market 22,589 23.04 2.95 1.02 Cascadilla Creek Mouth 1,163 2.39 0.80 2.06 0.33