Steven Effler, Susan O’Donnell, David Matthews, Carol Matthews, David O’Donnell,

1. The Disconnection Between Limnological Information and the Phosphorus “Total Maximum Daily Loads” (TMDL) Analysis for Onondaga Lake Steven Effler, Susan O’Donnell, David Matthews, Carol Matthews, David O’Donnell, Martin Auer, and Emmet Owens

2. the central role of phosphorus (P) loading Eutrophy at Onondaga Lake • oligo-mesotrophic before European settlement • cultural eutrophication has lead to • phytoplankton blooms • nuisance cyanobacteria • poor clarity • rapid hypolimnetic DO loss • fall DO depletion • fish exodus • high summer average epilimnetic [TP] (> 50 µgP·L-1)

3. inflow outflow lake load = inflow X concentration in the inflow mass/time volume/time mass/volume represented as throughout talk What are Loads? load

4. rural urban Types of Loads point loads non-point loads

5. current load (all sources) [TP] >50 µgP·L-1 ? current in-lake concentration [TP] = 20 µgP·L-1 established goal TP guidance value for mid-May to mid Sept. What is a TMDL Analysis? Total T M D L a quantitative framework to guide rehabilitation Maximum Daily Load determine the loading rate that will help meet an established goal

6. [TP] = 20 µgP·L-1 guidance value WLA/METRO TMDL Components LA/Tribs TMDL = WLA + LA + MOS WLA = Waste Load Allocation = METRO LA = allocation for non-point sources and natural background =Tribs MOS = margin of safety

7. Important Features of TMDL Analysis • accommodation of • important system specific characteristics • critical environmental conditions • recurring features of seasonality • consistency with format of standard • TP guidance value; summer average (mid-May to mid-September) epilimnetic concentration of 20 µg·L-1 (upper bound mesotrophy) • model: quantitative linkage between external loads and lake concentrations • synthesis of understanding of the system • behavior of phosphorus (P)

8. prevailing TP (TMDL) loading TMDL TP Load (2012) Tribs 65% Tribs. 32% MOS 10% METRO Effluent METRO 25% ME bypass total METRO = 68% NYSDEC TMDL Analysis 1998 • based on annual loads reported from Onondaga County monitoring program, 1990-1995 • TMDL analysis calls for 50% reduction in Tribs 90% reduction in METRO

9. TP loading METRO and tribs. outflow/Seneca River settling UML mixing LML settling sediment release UML = upper mixed layer, ~epilimnion LML = lower mixed layer, ~hypolimnion Model Framework Used in TMDL Analysis

10. Stage Starting Year METRO [TP] CSO’s Flow I 1998 550 µgP·L-1 62% reduction II 2006 120 µgP·L-1 85% reduction P TMDL/Management Plan/ACJ • phase I - composed of 3 stages (1998-2012) • continuing in-lake discharge III 2012 20 µgP·L-1* no further reduction • *METRO reductions have feasibility issues • also a LA (tributary) reductions of 50% during phase I • phase I I - update TMDL analysis in 2009

11.  ( )  previously presented information Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of particulate phosphorus (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading  presentation outline

12. D U Independent Long-Term Monitoring Program

13. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

14. Stratified River Flow D lake sediments U outlet - normal river lake sediments outlet - bi-directional flow salinity ~ 0.35 °/°° QI/S salinity ~1.1 °/°° • bi-directional/stratified flow in outlet • man made causes • lowering lake water surface elevation to that of river • salinity pollution of lake • net river flow into lake called QI/S throughout talk • water quality concerns – P load to lake • QI/S has not been quantified • river rich in bioavailable P

15. QI/S QMETRO four year summer average compared to METRO Estimate(s) of Seneca River Inflow (QI/S) • conducted chloride mass balance around the lake/river system for 4 years • estimates of QI/S varied year to year and seasonally • first approximation of summer average QI/S • river summer avg [TP]>60 µgP·L-1 • future METRO summer avg [TP]= 20 µgP·L-1

16. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

17. inflow outflow UML LML Interplay Between Lake Flushing Rate and Timing of the TP Guidance Value what is flushing rate? flushing rate = inflow rate ÷ lake volume high flushing rate – entering water remains in lake only a short time

18. summer average (mid-May through mid-Sept.,timing of guidance value) epilimnetic concentration of tracer calculated from model output response Implications of Lake Flushing: Formation of a Lake Response Curve • tracer injected for one month • model run • repeated each month • 30 year inflow record • formation of lake “response curve”

19. effect of interannual variation in runoff Implications of Lake Flushing: Response Curve for METRO Loads response curve driven by high flushing and timing of TP guidance value • critical loading interval April-August instead of annual loading rates • minor impact of loads received early fall through following spring • time averaging interval of METRO permit (12 months) not protective • interannual variations of Q are important

20. effect of interannual variation in runoff Implications of Lake Flushing: Response Curve for METRO Loads response curve driven by high flushing and timing of TP guidance value • critical loading interval April-August instead of annual loading rates • minor impact of loads received early fall through following spring • time averaging interval of METRO permit (12 months) not protective • interannual variations of Q are important • 12 month averaging appropriate for lakes with low flushing rates

21. Effect of Seasonality of TDP Loading Rate critical loading interval April-August instead of annual loading rates tributary loading rates are lower for April – August compared to annual loads

22. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

23. Inflow less dense Lake plunging underflow more dense Entry of Inflows • density () is a function of temperature (T) and salinity (S) • depth inflow enters is a function of density difference (T,S) between an inflow and the lake Density and Plunging Inflows

24. Inflow less dense Lake more dense Differences in Density large density difference (T,S) leads to plunging inflows Density and Plunging Inflows

25. Inflow less dense Lake UML more dense metalimnion H metalimnetic peak caused by plunging inflow Inflow Entry and Lake Stratification Density and Plunging Inflows

26. TMDL model Model Performance UML LML stratification model mixed (UML) plunging sub-model metalimnion H Stratification Model for Plunging Inflows

27. Stratification Model Application Density and Plunging Inflows

28. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

29. Bioassay Setup algal bioassay experiments to determine bioavailability of PP Bioavailability

30. TP Bioavailability of P According to Sources dissolved P particulate P Bioavailability

31. TP P available for algal growth high settling low settling Bioavailability of P According to Sources all forms of P are not equally available to support algal growth Particulate P inorganic P dissolved P organic P Bioavailability

32. tribs Bioavailability: Contrasting Contributions of TDP to TP • total dissolved phosphorus (TDP) is bioavailable • TDP/TP ratio as an indicator Bioavailability

33. tribs Contrasting Bioavailablity of PP consistent with literature Bioavailability

34. tribs Contrasting Bioavailability Rates of PP consistent with literature Bioavailability

35. Contrasting Associations of Bioavailable PP and Settling Site Onon. Ck. upstream Onon. Ck. downstream Ninemile Ck. METRO P Associations inorganic organic/inorganic inorganic organic Settling fast medium fast slow widely different deposition rates of bioavailable PP Bioavailability

36. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

37. no turbidity spectrophotometer cuvette high turbidity Analytical Issue TP Issue failure to correct for turbidity during the TP analysis leads to false high TP loads

38. Annual Load Estimates for 2000 Analytical Issue: Effect on TP Loads failure to correct for turbidity during the TP analysis leads to false high TP loads

39. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

40. common literature ranges Tributary TP Loads: Prevailing versus Literature UAL = unit area loads, kgP·km-2·yr-1 urban rural Sites Literature • lake tributaries are not rich targets • 50% reduction goal ?

41. Critical Evaluation of P TMDL for Onondaga Lake issues addressed in this talk • the Seneca River as source to the lake • lake flushing • “plunging inflows” • contrasting bioavailability of (PP) sources • analytical problems • loads/targets and feasibility • synthesis of above effects to estimate effective phosphorus loading presentation outline

42. algal growth What is Effective P Loading? effective P loading is that portion of the total loading that will support algae growth in the lake Synthesis

43. METRO Tributaries EffectiveTDP Loading: Prevailing (kg·d-1) apparent load annual productive season to productive layers effective load Synthesis

44. METRO Tributaries Effective PP Loading: Prevailing (kg·d-1) apparent load unblanked annual productive season bioavailable not deposited to productive layers effective load Synthesis

45. NYSDEC prevailing TP (TMDL) loading tribs. 32% METRO 80% tribs. 14% Sen. Riv. 7% METRO 86% METRO 68% tribs. 13% without river with river Effective P Loading Contributions TMDL TP Contributions realistic prevailing loading conditions Synthesis

46. bypass METRO tribs. Sen. Riv. manageable Futuristic Partitioning “Effective” P Loading Contributions stage III: METRO limit (20 µgP·L-1), other prevailing target richness only fraction of trib. load subject to management Synthesis

47. Conclusions NYSDEC TMDL Analysis is fatally flawed in the following ways...

48. TMDL Analysis Did Not Include 1. Seneca River load QI/S conclusions

49. inflow outflow UML LML TMDL Analysis Did Not Consider 2. implications of rapid lake flushing 12 month averaging for METRO effluent is not protective of the lake conclusions

50. Inflow less dense Lake UML more dense metalimnion H TMDL Analysis Did Not Consider 3. implications of the plunging inflows phenomenon model applied was an inappropriate framework conclusions