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Lake County Water Authority Nutrient Reduction Facility (NuRF). Lance Lumbard Water Resources Project Manager. Chairman Larry M. Everly, Sr. District 3. Everett Kelly District 5. Vice Chairman Sean M. Parks Member at large. Ann Wettstein-Griffin District 1. Nancy H. Fullerton
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Lake County Water Authority Nutrient Reduction Facility(NuRF) Lance Lumbard Water Resources Project Manager
Chairman Larry M. Everly, Sr. District 3 Everett Kelly District 5 Vice Chairman Sean M. Parks Member at large Ann Wettstein-Griffin District 1 Nancy H. Fullerton District 2 Lake County Water AuthorityBoard of Trustees Keith Farner Member at large Larry Everly, Jr. District 4
Lake Apopka Lake Apopka is presently at 65.46 ft. which is below the regulatory level of 67.25 ft. and below the minimum desirable level of 66.50 ft. The Apopka-Beauclair Lock and Dam discharge was reduced to 23 cfs, the base flow, on October 30, 2005 and then to 11 cfs on in June 2006 and has continued to flow at that rate since then.
Lake Eustis Lake Harris Lake Dora Lake Eustis is presently at 61.26 ft., Lake Harris is presently at 61.31 ft. and Lake Dora is presently at 61.32 ft. all below the regulatory level of 63.30 ft. for these lakes and at or below the minimum desirable level of 62.0 The Burrell spillway was reduced to base flow (30 cfs) in mid-March and has continued to flow at the base flow rate since then.
Lake Griffin Lake Griffin is presently at 58.05 ft, which is below the regulatory level of 59.25 ft. yet above the minimum desirable level of 58.0 ft. The Moss Bluff spillway was reduced to base flow (30 cfs) in mid-March and has continued to flow at the base flow rate since then.
Lak Lake Eustis Lake Dora Lake Beauclair Lake Apopka Harris Chain of Lakes
Problem Statement • Between 1991 and 2000, Apopka-Beauclair Canal discharged 13,300 kg (14 tons) of total phosphorus (TP) per year into Lake Beauclair causing persistent algal blooms in Lake Beauclair, Lake Dora and Lake Eustis.
Total Maximum Daily Loads(TMDLs) • Established by the Department of Environmental Protection in 2003 for Lakes Apopka, Beauclair, Carlton, Dora, Eustis, Harris, and Griffin • Provide a target for lake managers • Phosphorous TMDL is very important since phosphorus is generally limiting
Important Phosphorus TMDLs • Lake Apopka = 55 ppb • Lake Beauclair = 32 ppb
Apopka Marsh Flow-way • Maximum capacity of 200 cubic feet per second • Phosphorus removal estimated at 30% • Directs cleaner water downstream to Lake Beauclair and back into Lake Apopka GOOD BUT NOT QUITE ENOUGH!!!
Why do we need a NuRF? • Recent TP in Lake Apopka = 100 ppb • 30 % TP removal by flowway = 70 ppb • TMDL Target for Lake Beauclair = 32 ppb another 38 ppb to go!
Lake Beauclair April, 2006
Lak Lake Eustis Lake Dora Lake Beauclair NuRF Lake Apopka Harris Chain of Lakes
Proposed NuRF Site Location (254 acres)
Lock and Dam Storage Tank and Centrifuge ALUM Alum storage and pump building Clay Disposal Areas Floc Settling Ponds Dewatered Solids Storage Area
Expected Results if NuRF had been in place starting February, 2004 • Would have removed 15,371 kg phosphorus (17 tons) and treated 43 billion gallons (94% of total flow) • Would have met the TMDL for 2004-2006 • Increased water clarity and revegetation in Lake Beauclair and downstream
Sample Collected 6/26/06 Day 0 Day 1 Day 2 Day 3 Day 5 Day 6 Distilled Water Alum-Treated Flow-Way Water Untreated Flow-Way Water
Environmental Variables • Rainfall – without rainfall, there is no flow and the NuRF does not operate (doesn’t cost anything either) • Hurricanes!! • Internal nutrient loading – sediments may release nutrients under certain conditions • Vegetative response – more plants result in greater sediment stability (watch out for hydrilla)
Potential Lake Beauclair Replanting Area 200 acre increase
Cost Compared to Traditional Technologies • 50% less than stormwater retrofit • Average retrofit project removes about 50 pounds TP per year • That’s 246 retrofit projects!