Outline. Septic Systems: A brief overview. Collection systems. Countywide S2S Ranking Methodology Results Examples Nitrogen Loading Current Projects

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2 Outline Septic Systems: A brief overview Collection systems Countywide S2S Ranking Methodology Results Examples Nitrogen Loading Current Projects Moving forward/next steps County Goals Next Steps Other programs in the Treasure Coast

3 ~ Dry deposit Ton Figure 7. Nitrogen sources and pathways to streams, including direct discharges, runoff, leaching to groundwater~ subsurface t ile drainage to ditches, and precipitation d irectly into waters. Nit rogen in M innesota Surface Wat ers June M innesota Pollut ion Control Agency

4 Septic System Fact: There were four (4) major changes to the criteria for septic system placement, requirements and size of systems: Four significant periods of septic regulations* o Rules Prior to 72 o Change: 72 to 82 o Change: 83 to 97 o Change: 98 to present *(Chapter 64E Florida Administrative Code, Standards for On site Sewage Treatment and Disposal Systems, 3/98)

5 Locations of Septic Tanks in Indian River County 30,369 septic systems in Indian River County '. \.~ Lxations of Septic Tanks in Indian River Cow1ty F1orida n:;-~==- 1 "=- ---'- - Q ~... ' ' I ' I I / \ ~ - \ -=-- - '. -- ~~ ~-~ ' r --.r- ' -.l L. \

6 Jurisdiction Parcel with No Sewer Service Parcel Count % City of Fellsmere No Sewer Service, Built 1983 or After 648 No Sewer Service, Built Before % City of Sebastian No Sewer Service, Built 1983 or After 6,807 No Sewer Service, Built Before ,577 28% City of Vero Beach No Sewer Service, Built 1983 or After 486 No Sewer Service, Built Before ,000 5% County No Sewer Service, Built 1983 or After 11,419 No Sewer Service, Built Before ,814 63% Town of Indian River Shores No Sewer Service, Built 1983 or After 93 No Sewer Service, Built Before <1% Town of Orchid No Sewer Service, Built 1983 or After 1 <1% Data Sources Indian River County Utility Dept, 2013 City of Vero Beach Utility Dept, 2013 Indian River County Property Appraiser, 2013 Total 30,369

7 Indian River County Utility Department Service Area Excluding COVB, Fellsmere, Town of IRS 325 Subdivisions/ Communities Initial Ranking Importance Factor Weighting Final Ranking

8 Initial Ranking Seven (7) Factors and associated Index Numbers Index Number Factor Min. Max. Population Density 4(x1*)= 4 12(x2*)= 24 Proximity to Surface Waters 0.1(x1*)= (x2*)= 24 FEMA Flood Plain 0 12 Depth to Ground Water Table 4 12 Soil Condition 4 12 Age Surface Water Mgmt System 4 12 Age of Existing OSTDS 4 12 * 1 is minimum importance factor, and 2 is maximum importance factor 20.1 to 108

9 Importance Factor Weighting Description (Distance to Nearest surface water) Factor Adjacent to Indian River Lagoon (IRL) 2.0 Adjacent to Sebastian River (SR) 1.85 Adjacent to and downstream of spillways for IRFWCD Main, North or South relief canals or other streams/channels within 1 mile of IRL 1.85 Adjacent to and downstream of spillways for IRFWCD Main, North or South relief canals or other streams/channels within 1 mile of SR Adjacent to and within 1 mile upstream of spillways for IRFWCD Main, North or South relief canals or other streams from 1-2 miles of the IRL Adjacent to and within 1 mile upstream of spillways for SRID laterals Ca and L, and City of Sebastian waterways; or other Laterals ( C ), sub-laterals, streams / channels from 1-2 miles of the SR Adjacent to all other upstream surface waters 1.0 Adjacent to a surface water shall include any community within 100 ft. of a surface water

10 Population Density Population Density Index # x Importance Factor Score 2 units/ac 4 x I 4 to 8 2 to 4.8 units/ac* 4 to 12* x I 4 to24 > 4.8 units/ac 12 x I 12 to 24 *Sliding Scale, Index Number = 2.85d 1.7 D = Density ( 2-4.8) I = Importance Factor (1.0 to 2.0)

11 Flood Zone Designation Flood Zone Designation Index # / Score Outside 100 year Flood Hazard Area (FHA) 0 <= 1/3 community in FHA 4 1/3 to 2/3 of community in FHA 8 In Flood Zone 12

12 Depth to Groundwater Table Depth to Groundwater Table (GWT) Index # / Score > 48 inches 4 36 to 48 inches 5 24 to 36 inches 6 0 to 23 inches 10 above GWT 12

13 Soil Condition Soil Description Index # / Score* Slight (Slightly limited) 4 Moderate (Moderately limited) 5 Severe (Severely limited) 6 * Actual Score = calculate a weighted average number based on percentage of each soil classification within each community

14 Age of Surface Water Management System Age of Stormwater Mgmt. System (yr) Index # / Score After to to Before

15 Age of Existing OSTDS (septic system) Age of OSTDS/ Septic system Index # / Score 1998 to present to to Before

16 Example of an Initial Ranking Calculation Subdivisions Picked: Floravon Shores Sebastian Highlands Unit 05 River Shores Estates Units 1-4 Map Id. No Subdivision Name Importance Factor Population Density Index # Proximity of Surface Water Index # Flood Plain Index # Depth to Groundwat er Index # Soil Condition Index # Age of Surface Water Management System Index # Age of Existing OSTDS Index # Overall Score Initial Ranking 48 Floravon Shores Subdivision Sebastian Higlands Unit River Shores Estates Units

17 S2S Methodology INITIAL RANKING: Study evaluated 325 platted subdivisions within unincorporated IRC and City of Sebastian for the initial ranking. Factors used in the Initial Ranking Population Density - Importance factor assigned Proximity to Surface Waters Importance factor assigned Flood Plain Depth to Ground Water Table Soil Condition Age of Surface Water Management System Age of the Existing OSTDS Map Id. Subdivision Name Overall Score Initial Ranking 138 Hobart Landing Unit Orchid Island No Orchid Island No Hobart Landing Unit Hallmark Ocean Subdivision Ambersand Beach Sub No 1 & Floravon Shores Subdivision Naranja TR Shellmound Bch Replat of POR Sebastian Highlands Unit 02 Collier River Shores Estates Units Rain Tree Corner Subdivision Sebastian Highlands Unit Hobart Landing Unit Orchid Isle Estates Subdivision Amos (A of E) ** Kanawah Acres Verona Estates Subdivision Indian River Heights Units Diana Park Subdivision Dales Landing Subdivision Stevens Park Unit 1 & Pine Tree Park Units Little Portion Subdivision Replat OF Sebastian Highlands Unit Sebastian Highlands Unit Winter Grove Subdivision Tropic Colony Subdivision Halleluiah Acres Sebastian Highlands Unit Sebastian Highlands Unit

18 Final Ranking Re-prioritization of Initial Top 30 Sewer Cost per home ascending order Nitrogen reduction cost ascending order Presence of potable water

19 FINAL RANKING Initial Rankings were then sorted per the following factors to obtain the Final Ranking: Sewer Cost/home site ranked in ascending order of cost Nitrogen reduction cost ranked in ascending order of cost Presence of potable water Initial Final Pollutant Reduction Map Id. No Subdivision Name Ssytem Type Ranking Ranking lb/yr lb/yr/lot 48 Floravon Shores Subdivision 7 1 Gravity Sebastian Highlands Unit 02 Collier 9 2 Vacuum 1, Sebastian Highlands Unit Vacuum 13, Hobart Landing Unit Gravity Orchid Island No Low Pressure Sebastian Highlands Unit Vacuum 10, Orchid Island No Low Pressure Ambersand Beach Sub No 1 & Gravity 2, Sebastian Highlands Unit Vacuum 17, Sebastian Highlands Unit 03* Vacuum 1, Naranja TR Shellmound Bch Replat of POR 8 11 Low Pressure Sebastian Highlands Unit Vacuum 17, Orchid Isle Estates Subdivision Vacuum 2, Hobart Landing Unit Low Pressure The Sebastian top 30 Highlands ranked communities Unit 02 Replat from PG Part 1 have been re evaluated based on the 53 cost of pollutant reduction, presence of potable 38 water, 14 and cost Vacuum of sewer system 1, * 320 construction, River Shores and Estates re prioritized Units 1-4based on 10 these Factors: 16 Vacuum 1, Pine Initial Tree ranking Park Units of 1-4 the top 30 communities Already computed-previous Vacuum 6, slide Indian Sewer River Heights cost per Units home 1-9site ranked 18 in ascending 17 order Vacuum of cost 5, Sebastian Nitrogen Highlands reduction Unit 02 Replat cost PG 54 ranked 45 in ascending 17 order Vacuum of cost 3, Presence 3* of potable water 212 Rain Tree Corner Subdivision Low Pressure The formula used to re prioritize the communities was the sum of the 273 Diana Park Subdivision Low Pressure ranking Verona of above Estates listed Subdivision Factors, and an 17 adjustment 22 was Low made Pressure to the sum due to the Sebastian presence Highlands of potable Unit 13 water. The 29 results of 22 the Capital Vacuum Improvement 5, Program Prioritization Stevens are Park provided Unit 1 & on 2Table 9. Capital 21 Improvement 24 Vacuum Program 1, Priority Dales Recommendation Landing Subdivision Summary Low Pressure Amos (A of E) ** Low Pressure Hallmark Ocean Subdivision 5 24 Low Pressure Hobart Landing Unit Gravity Winter Grove Subdivision Low Pressure Kanawah Acres Low Pressure Tropic Colony Subdivision Gravity 1, Halleluiah Acres Low Pressure Little Portion Subdivision Replat OF Low Pressure Sebastian Highlands Unit 02 Replat PG 4* Vacuum Heritage Trace at Hobart * Gravity

20 SBS Estimation of Nitrogen Loading N Load per Household (2.5 persons) % Reduction Concentration Mg/l Load lb/yr From Household % After Drainfield 0 to 165 ft % 165 to 657 ft % > 657 ft < > 85% Nitrogen Soluble in water Not readily removed Drainfield Septic system converts organic nitrogen/ammonia to nitrate Removes 10% to 40% of nitrate Effluent Plume Up to 20% additional removal of nitrate through soil Dilution/dispersion reduces to drinking water standard (< 10 mg/l) given enough travel time and distance Studies show effluent plumes extend well beyond expectations (N > 10 mg/l) 426 ft (N > 10 mg/l) 1338 ft (detectable viruses)

21 Treatment via Standard Septic System and Drainfield (N Removed) Reference % N Removed Sayemuzzaman, % USEPA (1992) 10 40% USEPA (2002) [Anderson, 1994] 50% (estimate) USEPA (2002) [Siegrist, 2001] 10 20%

22 Estimation of Nitrogen Loading from Raw Sewage per Household Reference N Load per household (mg/l) (lb/yr) Sayemuzzaman, USEPA (1992) USEPA (2002) [Anderson, 1994] USEPA (2002) [Siegrist, 2001]

23 Estimation of Nitrogen Loading into Groundwater from Drainfield Nitrogen loadings per household (lb/yr) from septic system drainfield to groundwater. Reference Site Location N Load per household (mg/l) (lb/yr) Koppelman, 1978 Long Island, NY Gold, et al., 1990 Kingston, RI Weiskel and Howes, 1991 Buzzards Bay, MA Maizel, et al Chesapeake Bay Valiela, et al., 1997 Waquoit Bay, MA Reay, 2004 Coastal Plain, VA Roeder, 2008 Wekiva, FL Sayemuzzaman, 2015 St. Lucie Estuary, FL USEPA (1992) N/A USEPA (2002) [Anderson, 1994] N/A USEPA (2002) [Siegrist, 2001] N/A Wekiva Study (Ursin & Roeder, 2007) Central Florida N/A 30

24 CURRENT PROJECTS North Sebastian Septic to SewerPhase I Construction Phase- Pending approval of assessment North Sebastian Septic to SewerPhase II Design 90% Complete

25 Moving Forward/Next Steps County Goals Protecting Our Lagoon Work with the regulatory agencies, residents and other stakeholders to develop and implement the County Wide S2S plan Provide safe, reliable water and wastewater service Pursue grant dollars to minimize the overall impact to rate payers and be fair to all County citizens

26 Moving Forward/Next Steps Next Steps Approve Countywide Septic to Sewer Ranking by adopting the report prepared by Schulke, Bittle & Stoddard, LLC. Work with Community Development Long Range planning staff to incorporate the findings into the IRC 2030 Comprehensive Plan Chapter 3A, Sanitary Sewer Sub-Element for BCC review and approval at a later date. Make the report available on-line. Phase II : Phase III : Phase IV : Proposed changes to the county comprehensive plan Financing options and public outreach Encumber funds and implementation of the priority ranking plan