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

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

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

Types of Loads point loads non-point loads rural urban

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

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

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)

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

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

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

Critical Evaluation of P TMDL for Onondaga Lake 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  ( )   previously presented information presentation outline issues addressed in this talk

Independent Long-Term Monitoring Program U D

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

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

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

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

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

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

Implications of Lake Flushing: Response Curve for METRO Loads response curve driven by high flushing and timing of TP guidance value effect of interannual variation in runoff 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

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 Implications of Lake Flushing: Response Curve for METRO Loads response curve driven by high flushing and timing of TP guidance value effect of interannual variation in runoff

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

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

Lake more dense Density and Plunging Inflows Inflow less 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 plunging underflow

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

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

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

Stratification Model Application Density and Plunging Inflows

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

Bioassay Setup Bioavailability algal bioassay experiments to determine bioavailability of PP

Bioavailability of P According to Sources dissolved Pparticulate P TP Bioavailability

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

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

Contrasting Bioavailablity of PP Bioavailability consistent with literature tribs

Contrasting Bioavailability Rates of PP Bioavailability consistent with literature tribs

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

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

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

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

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

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

Critical Evaluation of P TMDL for Onondaga Lake 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 issues addressed in this talk

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

Effective TDP Loading: Prevailing (kg·d -1 ) Synthesis annual productive season to productive layers effective load apparent load METROTributaries

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

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

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

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

TMDL Analysis Did Not Include 1. Seneca River load Q I/S conclusions

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

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

4. contrasting bioavailability and settling characteristics of PP for different sources conclusions TMDL Analysis Did Not Consider model applied was an inappropriate framework

4. TP tributary concentrations of Onondaga County monitoring program are false high no turbidity high turbidity conclusions TMDL Analysis Did Not Recognize

5. target richness and feasibility of non-point load reduction goals conclusions 50% non-point loading reduction goals are not feasible rural urban TMDL Analysis Did Not Fully Consider METRO

6. apparent verses effective loads conclusions TMDL Analysis Did Not Consider effective load apparent load short-comings caused understatement of METRO’s role and overstatement of tributaries role METROTributaries

Important Features of TMDL Analysis accommodation of –important system specific characteristics –critical environmental conditions –recurring features of seasonality model – quantitative linkage between external loads and lake concentrations –synthesis of understanding of the system –behavior of phosphorus (P)

Conclusions existing P TMDL analysis developed by the NYSDEC cannot be considered a reliable basis to guide rehabilitation of the lake’s related problems conduct a valid P TMDL analysis for Onondaga Lake now (don’t wait until 2009) develop a plan to eliminate the Seneca River inflow reconsider management strategies Recommendations