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Peter D. O'Bryan From: Troy Rice [trice@sjrwmd.com] Sent: Monday, February 11, 2013 10:44 AM To: Peter D. O'Bryan Cc: jthurlowlippisch@comcast.net Subject: RE: SJRWMD Reponse to TCCLG's Letter to the Governor Hi Commissioner O'Bryan, It was nice speaking with you at last week's symposium. As you likely heard during the technical presentations on Thursday morning, high salinities were a bigger contributing factor to the bloom events in the northern portions of the lagoon (north of Melbourne) with the particular phytoplankton species predominate during the 2011 'Super Bloom` -- tolerant of higher salinity, and the Brown Tide species that bloomed in 2012 from Titusville north through much of Mosquito Lagoon, seeming to prefer hyper-saline conditions. Excess nutrient-rich freshwater and groundwater discharges to the Central IRL are still occurring daily through the C-1 Canal in Palm Bay,the 3 IRFWCD Relief Canals, Fellsmere Canal,Sotille Canal,the St.Sebastian River drainage including the Sebastian River Water Control District, and C-25 discharges at Fort Pierce being the largest contributors,that more than compensate for the salinities associated with ocean waters entering through the inlets on the incoming tides and evaporation from the surface waters of the lagoon. So it is very unlikely that a minimum-flows criteria of freshwater for the lagoon would ever need to be established from the C-54/USJRB, unless a persistent extreme drought of decadal proportions were to occur. Then I am certain that freshwater use priorities in that unlikely scenario would be allocated to potable uses. Freshwater discharges from the C-54 canal in the past did impact lagoon salinity and water quality as far north as Melbourne-Pineda segments of the lagoon, but had little impact north of the S.R. 518 causeway, where the past bloom's impacts were greatest, and in all likelihood additional freshwater discharges to the lagoon in 2011 and 2012 would have strengthened and expanded the 'secondary bloom' south of Melbourne to Ft. Pierce, providing additional nutrients of nitrogen and phosphorous for the phytoplankton to feed upon. I will certainly keep you and the TCCLG apprised of future findings associated with the seagrass loss investigations and any potential future management options(i.e. seagrass transplanting)that may be initiated to try and 'kick start' seagrass propagation in areas with heavy losses if associated water quality conditions are achieved. Thanks-Troy Troy Rice, Director Indian River Lagoon National Estuary Program St.Johns River Water Management District 525 Community College Pkwy, SE Palm Bay, Florida 32909 (321)984-4950 I C ►rt' r Y4y.... 1 g � • �- I �