Danielle Honour, P. E . , D.WRE Lake Tohopekaliga Nutrient Kimberly Lawrence Reduction Plan… Two Years Later Florida Stormwater Association Annual Conference June 12, 2014 Nutrient Reduction Plan Timeline Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Overview of Lake Toho Impairment • November 2010: Placed on Verified List by FDEP – Category 5: Impaired and Total Maximum Daily Load (TMDL) required – Initially impaired for nutrients due to increasing trend of Trophic State Index (TSI) • Osceola County and City of Kissimmee disagreed – Independent analysis showed no Upper Kissimmee Planning Unit TSI Impairment – Ambient nutrient content not related to algae Source: FDEP, 2011 Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Overview of Lake Toho Impairment (cont.) • FDEP reconsidered impairment – Agreed more research was needed – Imbalance of flora and fauna due to excessive macrophytes (hydrilla) • December 2011: Nutrient Reduction Plan (NRP) completed • February 2012: Final Listing – Category 4e : Impaired but ongoing restoration activities underway, no TMDL required Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later NRP Process Timing and Applicability ***Prior to TMDL adoption*** Evaluation • Causative pollutant is questionable or uncertain Strategic Nutrient Monitoring and Reduction Plan Initial Implementation • Highly managed or Assessment variable systems Final • Marginal impairment ‐ Impairment Listing & fluctuates over time Adoption Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later The TMDL Process Input based on findings Objectives, concerns, local during plan implementation knowledge, management activities, and monitoring Evaluation monitoring plan, data collection Strategic Implementation Monitoring and (e.g., BMAP) Initial Assessment NRP/RAP Review data and calculations, questions/ comments, reasonable assurance plan Ability to Development Challenge Final of Basin Impairment Management Action Plans Listing and (BMAPs) Adoption Development and Adoption of Total Maximum Public meetings, input and Public workshops, input and review on Daily Loads comments on plan development (TMDLs) appropriateness of targets set, initial and final allocations allocations and modeling What is a Nutrient Reduction Plan? Hybrid of a Basin Management Action Plan (BMAP) and Reasonable Assurance Plan (RAP) • Key Differences: – No water quality “targets” are set – No allocation of load reductions – Not a long term solution: stepping stone – Monitoring plan and research priorities will align to the goals and objectives identified by the stakeholders to determine future targets – Plan is not formally “adopted” Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Lake Tohopekaliga (Toho) Background • Upper Kissimmee River Basin • Headwaters to the Everglades • Watershed area = 473 sq. mi. • Lake = 34 sq. mi. • Class 3 fresh water lake • Popular for fishing, hunting, boating, bird watching and sightseeing • Economic importance Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later What Makes Lake Toho “Special” • Highly managed since the 1960s – Water level stabilization (1960s) – Sewage treatment plant effluent discharges (1940s to 1980s) – Major drawdowns to improve habitat (1969, 1979, 1987, 2004) – Introduction of Hydrilla species into the lake (1980s) – Change in Hydrilla management to support endangered snail kites • Impact of management activities still not fully understood Nutrient Reduction Plan Elements • Pollutant Load Analysis – Runoff‐based TN and TP Loads by Jurisdiction • Management Actions – BMPs to reduce TN and TP loads • Research Priorities – Hydrilla Literature Review • Strategic Monitoring Plan – Establish monitoring network • Track Implementation • Plan Commitment Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Tracking Implementation – 2014 Biennial Update Report • Coordination with FDEP on update elements • Accomplishments by participants • Research and monitoring – Monitoring results and trends – Research accomplishments • Implementation issues • Future activities • Feedback from FDEP – Detail on projects – Public education activities Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Lake Tohopekaliga Monitoring • Builds on existing efforts by municipal stakeholders and SFWMD • Data evaluated by WBIDs • Consistent with FDEP approach under Impaired Waters Rule – Mann Kendall test to determine statistical significance • Analyzed statistical long‐term (where available) trends • Tributary monitoring • Continued in‐lake monitoring Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Tributary Water Quality Trend Analysis Statistically Significant Results (2003 – 2012) • 95 percent confidence level (P < or = 0.05) • Remaining Tributary WBIDs –no trend WBID TKN NO2 TP Chl‐aAvg. Slope of /NO3 Concentration Trend (∆/yr) Hart Branch ↑ ‐‐ ‐‐ N/A 1.19 mg/l ‐0.941 Boggy Creek ↑↑ ‐‐ N/A 0.02,0.00 mg/l ‐0.001, ‐0.054 E. Lake Toho Drain ‐‐ ‐‐ ‐‐ N/A ‐‐ ‐‐ E. Lake Toho ‐‐ ↑↑↓ 4 ug/l 0.193 Shingle Creek ↓ ‐‐ ↑ N/A 0.83 mg/l 0.027 St. Cloud Canal ↓ ‐‐ ↑ N/A 0.76 mg/l 0.011 Mill Slough ↑ ‐‐ ‐‐ N/A 0.65 mg/l ‐0.206 ↑ Improving ↓ Declining - - No Trend Lake Toho Water Quality Trend Analysis Results (2005 – 2013) Parameter Statistically Slope of Significant Trend (∆/yr) Trend Total Phosphorus as PDecreasing‐0.002 Orthophosphate as P (mg/l) Decreasing 0.000 Total Kjeldahl Nitrogen as N (mg/l) Increasing 0.026 Nitrate/Nitrite (mg/l) None 0.000 Chlorophyll‐a None 0.000 Turbidity (NTU) Increasing 0.203 Color (PCU) Decreasing ‐4.355 pH (SU) Increasing 0.092 Conductivity (µmhos/cm) Increasing 2.140 Excluded 2003/2004 drawdown years due to possible anomalies Completed Literature Review on the Relationship Between Hydrilla and Nutrients • Information on the impact of large scale aquatic plant management on water quality is not readily available • Hydrilla has the ability to retrieve nutrients from both roots and shoots to varying degrees • Derives primary nutrition from bottom sediments • Water column nutrients have minimal influence on the ability to colonize large areas of the KCOL • Estimated sediment reserves of N&P and internal cycling of nutrients are adequate to sustain populations for extended periods of time Water Column Nutrients and Abundant Hydrilla Growth on Lake Tohopekaliga (Netherland et. al, 2012) Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Completed Literature Review on the Relationship Between Hydrilla and Nutrients • Hydrilla Growth on Lake Toho will continue – Shallow nature of lake – Large sediment pools of N&P – Water schedules that promote stabilization – Physiological adaptations – Invasive traits of the plant – Even if inflowing N&P are reduced Water Column Nutrients and Abundant Hydrilla Growth on Lake Tohopekaliga (Netherland et. al, 2012) Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Here Comes the Lake Okeechobee BMAP… • BMAP process initiated in 2013 • Drainage area spans over 3.5 million acres • Lake O TMDL – Target Concentration 0.04 mg/l TP – Target Load 140 MT/year (~63% reduction) • Northern Six Sub‐Watersheds is the focus of the BMAP – Upper Kissimmee – Lower Kissimmee Lake O Watershed Land Use % – Lake Istokpoga – Indian Prairie Agriculture 51.2 – Fisheating Creek Natural Areas 35.7 – Taylor Creek/Nubbin Slough Urban 11.9 Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Lake O BMAP TP Loading Summary Attenuated TP Reductions Sub‐Watershed Area (ha) TP Load %Load (MT/yr) (MT/yr) Fisheating Creek 128,708 79.0 19% 6.01 Indian Prairie 111,927 72.7 17% 6.22 Lake Istokpoga 159,529 18.3 4% 132 Lower Kissimmee 173,687 103.0 25% 19.06 Taylor Creek/Nubbin Slough 80,045 100.8 24% 22.06 Upper Kissimmee* 416,189 46.4 11% 4.32 Total 1,070,085 420.2 100% 59.0 *Lake Toho located in Upper Kissimmee Sub‐watershed What is the non‐attenuated source reduction needed to meet the attenuated reduction requirements? Cost per lb. reduced in Lake O become $$$ Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Upper Kissimmee’s Sub‐Watershed • Upper Kissimmee’s Sub‐Watershed – Lowest average TP concentration – Highest Discharge • Stakeholder ability to manage flow? Water Years 2001-2013 Source: FDEP, 2013 Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Lake Toho’s Role in the BMAP • Lake Toho Watershed – Located in Upper Kissimmee Sub‐ Watershed – 11% of the area in Lake O Northern Tributary Sub‐Watersheds – Contains the majority of the urban area (MS4) – Lake Toho Average TP: 0.05 mg/l Source: SFWMD, 2011 Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Stakeholders Have High Hopes for NRP’s Role in Lake O BMAP • Gives NRP stakeholders a “head start” • Strategic monitoring already in place • Demonstrated TP has been consistently decreasing in Lake Toho • Stakeholders already have projects and implementation underway – Streamlines process of submitting projects – Loads reductions will be re‐calculated due to different tools Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later As a Result, Water Quality Mandates are Driving the County’s Master Planning Process • County Comprehensive Plan requires stormwater master plan update every 5 years – Previous updates historically “flood control” driven • Designed a Master Plan to support existing and anticipated water quality requirements • Completed County‐Wide Master Plan Update in early 2014 Lake Tohopekaliga Nutrient Reduction Plan –2 Years Later Master Plan Designed to Support Existing and Anticipated Water Quality Requirements • Water Quality Regulatory Framework (TMDL,