Outline Septic Systems: A brief overview Collection systems - - PowerPoint PPT Presentation

• 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

Outline

~

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 directly into waters.

Nit rogen in M innesota Surface Waters • June 20 13 M innesota Pollution Control Agency

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*

• Rules Prior to ‘72
• Change: ’72 to ‘82
• Change: ’83 to ’97
• Change: ’98 to present

*(Chapter 64E‐Florida Administrative Code, Standards for On‐site Sewage Treatment and Disposal Systems, 3/98)

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 -

• ~

.....

\

. --

• =-- - '·

. -

• ~

~ ~-~

' r --.r-

'

• .l

L

.

• \

'

'

'

I '·

I

Jurisdiction Parcel with No Sewer Service Parcel Count %

City of Fellsmere No Sewer Service, Built 1983 or After 648 No Sewer Service, Built Before 1983 464 4% City of Sebastian No Sewer Service, Built 1983 or After 6,807 No Sewer Service, Built Before 1983 1,577 28% City of Vero Beach No Sewer Service, Built 1983 or After 486 No Sewer Service, Built Before 1983 1,000 5% County No Sewer Service, Built 1983 or After 11,419 No Sewer Service, Built Before 1983 7,814 63% Town of Indian River Shores No Sewer Service, Built 1983 or After 93 No Sewer Service, Built Before 1983 60 <1% Town of Orchid No Sewer Service, Built 1983 or After 1 <1% Total 30,369

Data Sources Indian River County Utility Dept, 2013 City of Vero Beach Utility Dept, 2013 Indian River County Property Appraiser, 2013

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

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*)= 0.1 12(x2*)= 24 FEMA Flood Plain 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 20.1 to 108

* 1 is minimum importance factor, and 2 is maximum importance factor

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
• r South relief canals or other streams from 1-2 miles of the IRL

1.7 1.4

• 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 1.3

• 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

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)

Flood Zone Designation

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

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

Age of Surface Water Management System

Age of Stormwater Mgmt. System (yr) Index # / Score After 2008 2 1999 to 2008 4 1982 to 1998 6 Before 1982 12

Age of Existing OSTDS (septic system)

Age of OSTDS/ Septic system Index # / Score 1998 to present 4 1983 to 1997 6 1972 to 1982 10 Before 1972 12

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 2.00 9.33 18.24 8.00 10.00 12.00 12.00 6.00 75.57 7 58 Sebastian Higlands Unit 05 1.70 12.30 16.66 0.00 10.00 12.00 12.00 6.00 68.96 12 320 River Shores Estates Units 1- 4 2.00 14.36 8.56 4.00 10.00 12.00 12.00 10.00 70.92 10

S2S Methodology 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 2 89.19 1 17 Orchid Island No. 1 85.49 2 18 Orchid Island No. 2 84.65 3 139 Hobart Landing Unit 3 82.37 4 2 Hallmark Ocean Subdivision 78.45 5 1 Ambersand Beach Sub No 1 & 2 75.73 6 48 Floravon Shores Subdivision 75.57 7 131 Naranja TR Shellmound Bch Replat of POR 74.05 8 52 Sebastian Highlands Unit 02 Collier 73.05 9 320 River Shores Estates Units 1-4 70.92 10 212 Rain Tree Corner Subdivision 69.63 11 58 Sebastian Highlands Unit 05 68.96 12 137 Hobart Landing Unit 1 68.28 13 19 Orchid Isle Estates Subdivision 68.27 14 275 Amos (A of E) ** 67.51 15 213 Kanawah Acres 67.41 16 199 Verona Estates Subdivision 67.38 17 291 Indian River Heights Units 1 -9 66.96 18 273 Diana Park Subdivision 66.85 19 49 Dales Landing Subdivision 66.33 20 278 Stevens Park Unit 1 & 2 66.17 21 272 Pine Tree Park Units 1-4 65.24 22 196 Little Portion Subdivision Replat OF 64.85 23 50 Sebastian Highlands Unit 01 63.99 24 57 Sebastian Highlands Unit 04 63.78 25 143 Winter Grove Subdivision 62.82 26 207 Tropic Colony Subdivision 62.60 27 32 Halleluiah Acres 62.50 28 68 Sebastian Highlands Unit 13 62.30 29 51 Sebastian Highlands Unit 02 62.09 30

INITIAL RANKING:

Study evaluated 325 platted subdivisions within unincorporated IRC and City of Sebastian for the initial ranking.

Final Ranking

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

FINAL RANKING

Ini nitial R Rankings s wer ere t e the hen so sorted p per er the f e follo

• llowing

factors t to o

• btain t

the he 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

The top 30 ranked communities from Part 1 have been re-evaluated based on the cost of pollutant reduction, presence of potable water, and cost of sewer system construction, and re-prioritized based on these Factors:

• Initial ranking of the top 30 communities Already computed-Previous slide
• Sewer cost per home site – ranked in ascending order of cost
• Nitrogen reduction cost – ranked in ascending order of cost
• Presence of potable water

The formula used to re-prioritize the communities was the sum of the ranking of above listed Factors, and an adjustment was made to the sum due to the presence of potable water. The results of the Capital Improvement Program

Prioritization are provided on Table 9. – “Capital Improvement Program Priority Recommendation Summary”. Map Id. No Subdivision Name Initial Ranking Final Ranking Ssytem Type Pollutant Reduction lb/yr lb/yr/lot

48 Floravon Shores Subdivision 7 1 Gravity 949.44 26.37 52 Sebastian Highlands Unit 02 Collier 9 2 Vacuum 1,027.53 36.70 58 Sebastian Highlands Unit 05 12 3 Vacuum 13,577.22 29.20 138 Hobart Landing Unit 2 1 4 Gravity 965.00 37.12 18 Orchid Island No. 2 3 5 Low Pressure 737.76 33.53 57 Sebastian Highlands Unit 04 25 5 Vacuum 10,018.99 22.87 17 Orchid Island No. 1 2 7 Low Pressure 473.15 33.80 1 Ambersand Beach Sub No 1 & 2 6 8 Gravity 2,802.36 33.36 50 Sebastian Highlands Unit 01 24 8 Vacuum 17,256.07 22.89 56 Sebastian Highlands Unit 03* 31 10 Vacuum 1,580.57 9.41 131 Naranja TR Shellmound Bch Replat of POR 8 11 Low Pressure 326.94 29.72 51 Sebastian Highlands Unit 02 30 11 Vacuum 17,845.33 16.96 19 Orchid Isle Estates Subdivision 14 13 Vacuum 2,428.71 36.25 139 Hobart Landing Unit 3 4 14 Low Pressure 270.20 38.60 53 Sebastian Highlands Unit 02 Replat PG 2* 38 14 Vacuum 1,268.19 19.22 320 River Shores Estates Units 1-4 10 16 Vacuum 1,663.11 13.86 272 Pine Tree Park Units 1-4 22 17 Vacuum 6,221.58 11.85 291 Indian River Heights Units 1 -9 18 17 Vacuum 5,759.18 7.46 54 Sebastian Highlands Unit 02 Replat PG 3* 45 17 Vacuum 3,319.68 25.73 212 Rain Tree Corner Subdivision 11 20 Low Pressure 444.68 27.79 273 Diana Park Subdivision 19 21 Low Pressure 587.62 27.98 199 Verona Estates Subdivision 17 22 Low Pressure 105.88 9.63 68 Sebastian Highlands Unit 13 29 22 Vacuum 5,988.17 9.64 278 Stevens Park Unit 1 & 2 21 24 Vacuum 1,657.82 5.47 49 Dales Landing Subdivision 20 24 Low Pressure 169.33 24.19 275 Amos (A of E) ** 15 24 Low Pressure 46.71 23.35 2 Hallmark Ocean Subdivision 5 24 Low Pressure 115.80 38.60 137 Hobart Landing Unit 1 13 24 Gravity 136.40 8.02 143 Winter Grove Subdivision 26 29 Low Pressure 632.10 24.31 213 Kanawah Acres 16 29 Low Pressure 164.70 13.73 207 Tropic Colony Subdivision 27 31 Gravity 1,114.80 7.69 32 Halleluiah Acres 28 32 Low Pressure 231.60 38.60 196 Little Portion Subdivision Replat OF 23 33 Low Pressure 201.17 9.58 55 Sebastian Highlands Unit 02 Replat PG 4* 69 34 Vacuum 893.08 15.95 136 Heritage Trace at Hobart * 281 35 Gravity 0.00 0.00

SBS Estimation o

• f Nitrogen Loading
• 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)

N Load per Household (2.5 persons) % Reduction Concentration Mg/l Load lb/yr From Household 70.0 52.8 0% After Drainfield 0 to 165 ft 50.97 38.6 27% 165 to 657 ft 12.92 9.78 81% > 657 ft < 10 7.55 > 85%

Trea eatment vi via S Standard S Sep eptic tic S System a and Drainfield (N R Rem emoved ed)

Reference % N Removed Sayemuzzaman, 2015 30% USEPA (1992) 10 – 40% USEPA (2002) [Anderson, 1994] 50% (estimate) USEPA (2002) [Siegrist, 2001] 10 – 20%

Estim timatio ion of

• f N

Nitrogen Loa Loadin ing f from R Raw S Sewage p per er Househ ehol

• ld

Reference N Load per household (mg/l) (lb/yr) Sayemuzzaman, 2015 35.0 26.4 USEPA (1992) 45.0 – 55.0 34.0 – 41.5 USEPA (2002) [Anderson, 1994] 19.0 – 53.0 14.3 – 40.0 USEPA (2002) [Siegrist, 2001] 40.0 – 100.0 30.1 – 75.5

Estimation of Nitrogen L Loading g into G Groundwater f from Dr Drainfiel eld

• 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 16.8 12.7 Gold, et al., 1990 Kingston, RI 23.3 17.6 Weiskel and Howes, 1991 Buzzards Bay, MA 11.7 – 19.7 8.8 – 14.9 Maizel, et al. 1997 Chesapeake Bay 17.5 – 25.6 13.2 – 19.3 Valiela, et al., 1997 Waquoit Bay, MA 21.2 16.0 Reay, 2004 Coastal Plain, VA 17.5 – 21.2 13.2 – 16.0 Roeder, 2008 Wekiva, FL 23.0 17.4 Sayemuzzaman, 2015

• St. Lucie Estuary, FL

24.5 18.5 USEPA (1992) N/A 35.8 – 65.6 27.0 – 49.5 USEPA (2002) [Anderson, 1994] N/A 21.6 16.3 USEPA (2002) [Siegrist, 2001] N/A 32.0 – 90.0 24.2 – 68.0 Wekiva Study (Ursin & Roeder, 2007) Central Florida N/A 30

CURRENT PROJECTS

• North Sebastian Septic to Sewer-

Phase I

Construction Phase- Pending approval

• f assessment
• North Sebastian Septic to Sewer-

Phase II

Design 90% Complete

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

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 : Proposed changes to the county comprehensive plan Phase III : Financing options and public outreach Phase IV : Encumber funds and implementation of the priority ranking plan