Marco Island s Septic Systems Their Potential Impacts on Health and Water Quality

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1 Marco Island s Septic Systems Their Potential Impacts on Health and Water Quality City of Marco Island October

2 Agenda Septic Systems on Marco Island Sewer System Implementation Acknowledgements Jon Iglehart Director, South District Office, Florida Department of Environmental Protection (FDEP) Gary Lytton Director, Florida FDEP/National Oceanographic Atmospheric Administration, Rookery Bay National Estuary Research Reserve Michael Shirley Ph.D. Research Coordination Rookery Bay National Estuary Research Reserve 2

3 The City s number 1 priority is affordably preserving the highest quality of life for Marco Island residents 3

4 Marco s multiple waterways create a unique setting as a premier coastal community 65% of Marco Island residential properties are on water 75% of those properties use septic systems High density community 4

5 The original vision for the Island recognized that septic systems are not ideal in coastal communities There will be no septic systems on the Island Deltona Corporation However, exponential growth and immediate need for wastewater treatment resulted in septic systems 5

6 Sewage treatment can be accomplished in two ways Central wastewater treatment system (including sewers) Marco Island Wastewater Treatment Plant 6

7 Sewage treatment can be accomplished in two ways Onsite wastewater treatment system Cleanout Septic Tank Sewer Pipe Distribution Leachfield 7 Typical Septic System

8 A properly functioning septic system collects and treats wastewater Normal Conditions Leachfield Distributes wastewater evenly over soil Seawall Septic Tank Removes solids and some organics Scum Sludge Effluent Area Where Treatment Occurs Septic tank effluent is degraded by bacteria in the soil layer below the leachfield 8

9 A properly functioning septic system collects and treats wastewater High Tide Seawall Scum Effluent Sludge Area Where Treatment Occurs Soils are Flooded No Treatment Occurs Pollutants Enter Waterways 9

10 Tidal cycle affects flow of pollutants toward waterway Leachfield Seawall High Tide 10 Groundwater Table Tidal-influenced groundwater creates steep local gradient causing faster movement of contaminants to surface water Canal Low Tide 2 Times a Day

11 Off-season effects when septics are not in use Septics Rely on Bacteria in Soils to Remove Pollutants 11 Household Waste Septic Treated Effluent Soil Treated Effluent 1. Septics In Use Septic Tank Soils Groundwater 2. Off-season, Septics Not in Use Bacteria Has No Food and Dies Bacteria in Soils Feed on The Septic Effluent (Pollutants) 3. Season Begins No Bacteria to Eat (Treat) Pollutants Untreated Effluent Enters Groundwater

12 Wastewater entering groundwater travels horizontally toward nearest waterway Septic Tank Plume Carrying Waste To Canal Leachfield 12

13 13 Septic systems remove solids, BOD, and fecal coliforms Untreated Residential Wastewater Septic System Effluent WWTP Effluent Fecal Coliforms (FC) Fecal Coliforms (FC) Total Suspended Solids (TSS) Total Suspended Solids (TSS) Biochemical Oxygen Demand (BOD) Biochemical Oxygen Demand (BOD) Nitrogen (N) Nitrogen (N) Phosphorus (P) Phosphorus (P) FC TSS BOD N P FC TSS BOD N P

14 14 Wastewater plant is most efficient and reliable pollutant removal system Septic System Effluent WWTP Effluent FC TSS BOD N P FC TSS BOD N P

15 Septic systems do not remove much nitrogen, which is converted to nitrate and enters surface water * Organic Nitrogen is converted to Ammonia Ammonia is converted to Nitrates Household Wastewater Influent Septic Tank Effluent Native Soil Organic Nitrogen (Urine, Fecal Matter, Food Waste) mg/l Ammonia (NH 3 ) To Groundwater To Surface Water Nitrate mg/l 15 * Based on EPA Information

16 Septic systems do not remove all Phosphorus * Household Wastewater Influent Some Phosphorus taken up by bacteria Septic Tank Effluent Phosphorus adsorbed; diminishes with time Native Soil Phosphorus 20 mg/l Household Chemical and other Cleaners Phosphorus 18 mg/l To Groundwater To Surface Water Phosphorus mg/l 16 * Based on EPA Information

17 Pollutants that septic systems do not eliminate are harmful to the environment Septic systems not designed to remove Nitrogen (N) and Phosphorus (P) Nutrients Nutrients promote algae growth in canals Algae die, are decomposed by bacteria Septic Tank Canal Oxygen levels are reduced 17 Low oxygen destroys habitat for fish and shellfish

18 Arnade, L.J. (1999) in an article titled Seasonal Correlation of Well Contamination and Septic Tanks Distance, (National Research Council 1998) Many people do not realize or acknowledge the potential for septic tanks to [contaminate] and the epidemiological effects that may be caused by this process. Fecal coliform, nitrates, and phosphorus present in septic tank effluent are responsible for such diseases as shigellosis, typhoid fever, gastroenteritis, blue baby syndrome. 18

19 Lipp, E.K., Farrah, S.A. and Rose, J.B. (2001) in a paper titled Assessment and Impact of Microbial Fecal Pollution and Human Enteric Pathogens in a Coastal Community Tracer studies demonstrate rapid movement of viruses from septic tanks into nearby coastal waters. Viruses may migrate under saturated conditions beyond current setback distance required between the drain field and wet weather water table. Under current regulations Florida soils may not be able to filter viral pathogens adequately. Infectious enteroviruses were detected throughout the study area, indicating a widespread contamination problem and a potential public health risk. 19

20 Paul, J.H., et al. (1995), in a paper titled Viral Tracer Studies Indicate Contamination of Marine Waters by Sewage Disposal Practices in Key Largo, Florida Our work suggests that the on-site disposal practices employed in Key Largo lead to contamination of the marine surface waters. These practices could pose a health risk to the human population, when contact (swimming or diving) occurs, particularly in the canals, or from the consumption of seafood harvested from these canals. 20

21 Dale W. Griffin, et al. (1999), in an article titled Detection of Viral Pathogens by Reverse Transcriptase PCR and of Microbial Indicators by Standards Methods in the Canals of the Florida Keys Seventy-nine percent of the sites were positive for the presence of enteroviruses by reverse transcriptase PCR (polioviruses, coxsackie A and B viruses, and echoviruses). Sixty-three percent of the sites were positive for the presence of hepatitis A viruses. Ten percent of the sites were positive for the presence of Norwalk viruses. Ninety-five percent of the sites were positive for at least one of the virus groups. These results indicate that the canals and nearshore waters throughout the Florida Keys are being impacted by human fecal material carrying human enteric viruses through current wastewater treatment strategies such as septic tanks. Exposure to canal waters through recreation and work may be contributing to human health risks. 21

22 Water quality can be adversely impacted by use of septic systems in coastal communities 22 Throughout Florida, septic tanks have proven to be problematic in coastal areas of high concentration of septic tanks. Nutrients Viruses Pharmaceuticals

23 Known historical monitoring in Marco Island Marco Island Marine Lab (Deltona) Collier County Government Complaint-driven Dept. of Health - Collier County current Healthy Beaches Program City of Marco Island present FDEP Rookery Bay 23

24 Total Nitrogen seasonal pattern 1.2 Total Nitrogen (average ppm) Early Dry Season Late Dry Season Early Wet Season Late Wet Season Marco Past Marco Present DEP Rookery Bay Analysis 9/05 24

25 Fecal coliform bacteria seasonal pattern 20 Fecal Bacteria (average MPN) Marco Past Marco Present Early Dry Season Late Dry Season Early Wet Season Late Wet Season DEP Rookery Bay Analysis 9/05 25

26 Fecal coliform bacteria comparison 12 Fecal Bacteria (Average MPN) SEWERED UN-SEWERED 1/2 SEWERED DEP Rookery Bay Analysis 9/05 26

27 Samples show that septic systems are allowing human-generated wastes into our waterways Test for caffeine (µg/l) October

28 Irrefutable evidence indicates that septic systems will degrade waterways The Collier County Conservancy The Naples Bay Study 1979: There seemingly is no lack of agreement, as to the immediate need for sewers for East Naples, and the added capacity urgently needed for the Naples Sewage Plant. It is up to interested citizens... to achieve the corrective programs to protect their investment here and their way of life. The facts are irrefutable and without argument 28

29 Irrefutable evidence indicates that septic systems will degrade waterways The Collier County Conservancy The Naples Bay Study 1979: No amount of criticism by those, who wish it would go away, can solve, or any longer delay the accounting that is now upon us Without improvements the results will be the same tragedies as in Miami, Tampa and other Florida communities, who chose to ignore them. 29

30 The latest threat to river? Leaking septic tanks Ft. Pierce Tribune - October 14, 2005 State health and environmental officials say they believe that septic tanks around Five Mile Creek in Fort Pierce and Sagamore Waterway in Port St. Lucie may be leaking into the ground water. 30 One scenario being considered is that the tanks were all properly situated, but the past several years of heavy rain and two hurricanes may have raised the ground water level so high it is now flowing around the septic tank fields. That would cause sewage to percolate into the ground water and eventually out to the river.

31 Improving water quality requires several approaches Capture and treat stormwater run-off Reduce the use of fertilizers Address dumping of boat wastes Ensure optimal wastewater treatment Continued improvements to sewage treatment system Eliminate septic systems 31

32 Improving water quality requires several approaches Capture and treat stormwater run-off Reduce the use of fertilizers Address dumping of boat wastes Ensure optimal wastewater treatment Continued improvements to sewage treatment system 32

33 Plans to improve sewage treatment system to ensure public health 1976 Present: No sewage spills from WWTP Effluent leaves WWTP Is reused or Is injected into deep injection wells Current Plans: Standby generators Critical pump stations Membrane bioreactor 33

34 Improving water quality requires several approaches Capture and treat stormwater run-off Reduce the use of fertilizers Address dumping of boat wastes Ensure optimal wastewater treatment Eliminate septic systems 34

35 Desire for better water quality is driving coastal communities to eliminate septics Naples, Collier County Monroe County Sarasota Cape Coral Sanibel Fort Lauderdale 35

36 Sequencing of sewer installation into districts will match plant and system capacity to neighborhood needs Year 1 Tigertail District Year 2 North Marco District Year 4 Kendall District Year 5 Gulfport District Year 2 North Barfield District Year 2 Sheffield District Year 6 Goldenrod District Year 1 South Barfield District Year 4 Mackle Park District Year 6 Copperfield District Year 3 Lamplighter District Year 2 West Winterberry District 36 Year 7 Estates District Year 5 East Winterberry District

37 Implementation requires completion of three system components Homeowner Hook-up and Tank Removal Neighborhood Collection System Wastewater Treatment Plant Expansion 37

38 Implementation requires completion of three system components 1. Homeowner to install lateral sewer line connection to sewer main $1,680 (MWH est., 2004 Dollars) $2,000 (Boyle est., 2006 Dollars) Homeowner s Responsibility 38 Crush and fill Septic Tank City s Right-of-Way Main

39 Implementation requires completion of three system components 2. Neighborhood Collection System MWH Estimate: $8,000 - $14,000 Per ERC ( 04 Dollars) Boyle Estimate: * Will vary by district $12,000 * Per ERC ( 06 Dollars) 39

40 Implementation requires completion of three system components 3. Wastewater Treatment Plant Expansion MWH $4,945 - $6,134 Estimate: Per ERC ( 04 Dollars) MWH-Public Works Estimate: $ $6,298 Per ERC ( 06 Dollars) 40

41 Total Cost to Expand Sewer System and WWTP Infrastructure Neighborhood Collection Assessment * (Varies by District) $12,000* Homeowner s Estimated Cost: $20,300 Or Actual Cost (Whichever is Less) WWTP Expansion Assessment $ 6,298 Homeowner Connection Cost Less Grants $ 2,000 Actual 41

42 Eliminating septic systems is our most cost effective guarantee to: Ensure our public health Maintain our pristine waters Maintain our quality of life Ensure our legacy for future Protect our investment in property 42

43 Jon Iglehart Director, South District Office, Florida Department of Environmental Protection (FDEP) 43

44 Q & A Ensure our public health Maintain our pristine waters Maintain our quality of life Ensure our legacy for future Protect our investment in property City of Marco Island 44