Crediting On-Site Wastewater Treatment Systems in the Bay

Watershed

Photo Credit: The Animal Foundation in Las Vegas Nevada, treats its wastewater

by a Tidal Flow Wetland Living Machine® system.

Photo Credit: Vegetative Tertiary Filter by WetlandsPacific Corporation in

Vancouver, British Columbia

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Thursdays @ 12:00 EST

• December 2: Meeting the Chesapeake Bay Restoration

Requirements for Industrial Sites in MD

• December 4: Verification Simplified! Urban BMP

Verification for Local Governments

• December 11: The Best Urban BMP in the Bay Award!

Speaker Info

Victor D'Amato, PE, Tetra Tech, victor.damato@tetratech.com

Ning Zhou, Virginia Polytechnic Institute, zhou.ning@epa.gov

Cecilia Lane, Chesapeake Stormwater Network, watershedgal@hotmail.com

Poll Question #1

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Poll Question #2

Tell us a little about yourselves…who are you representing today?

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Poll Question #3

What proportion of homes in Maryland rely on septic systems for treatment of their wastewater?

• 0%

• 10%

• 20%

• 30%

• 40%

Today’s Agenda

• Septics: The Silent Source

• Crediting for On-site Wastewater Treatment Systems

• Update on Nutrient Attenuation Panel

• FAQs

• Webcast Resources

The Process

• Outlined in the WQGIT BMP Review Protocol (WQGIT, 2014)

• BMP Expert Panel reviews existing research set of recommendations

• Recommendations used to derive methods and/or protocols to derive nutrient removal rates for the proposed BMP

BMP EXPERT PANEL

WASTEWATER WORKGROUP

WATER QUALITY

GIT

WATERSHED TECHNICAL

WORKGROUP

Septics: The Silent Source?

• 4 kg TN/person/year

• Average household size: 2.5 ppl

• = 10 kg TN/household/year

• = 22 lbs TN/household/yr

How Urban Land Cover is Represented in the

Current Version of CBWM

Impervious Cover Pervious Cover

Acres in Watershed 1 1,269,030 3,398,732 Average TN Load 2 15.5 lbs/ac/yr 12.4 lbs/ac/yr 1 Acres as reported in most recent CBWM version 5.3.2 2 Average values, as reported in Tetra Tech 2014a and ESC EP, 2014 (construction sites), although actual values are regionally variable

How Septic Load is Calculated in the Current

Version of CBWM At the edge of drain field:

Septic N Load (lbs/yr) = Population *8.91586 (lbs/person, yr) *BMP Rate

At the edge of stream:

Septic N Load (lbs/yr) = Population *8.91586 *BMP Rate* Pass-through rate

Delivered N Loads to the Bay (lbs/yr)

= Population *8.91586 *BMP Rate* Pass-through rate *River Delivery Rate

Pass-through rate (%) = 1- Attenuation Rate (%)

How Septic Load is Calculated in the Current

Version of CBWM Septic N pass-through rate – Percent of septic N loads that

pass through the ground soil and reach the edge of stream

Current septic N pass-through rate used in the model is 40% for everywhere in the Bay watershed except MD.

MDE guidance on Septic N Load Delivery Rates

• 80% for septic systems within the Critical Area (1,000 feet from tidal surface water)

• 50% for septic systems outside the Critical Area and within 1,000 feet of non-tidal waters

• 30% for all other septic systems

Agriculture 44.08%

Urban Runoff 16.73%

Wastewater 16.20%

CSO 0.58%

Septic 3.59%

Other 18.81%

2013 TN Delivered Loads by Sources

5.16

8.42 8.33 8.75

6.19

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

1985 2009 2011 2013 2025

TN D

eliv

ere

d L

oad

s (m

il lb

s/yr

) Septic TN Delivered Loads

(mil lbs/yr)

87.59 (0%)

50.59 (42%) 43.01

(51%) 39.47 (55%)

37.95 (57%)

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

1985 2009 2011 2013 2025

TN D

eliv

ere

d L

oad

s (m

il lb

s/yr

) Wastewater TN Delivered Loads (mil lbs/yr)

and Reduction (%) from 1985

Sector

2009 Load

Target Load % Reduction Needed to Meet Target

Million pounds per year

Forest 7.00 7.00 0

Atm. Deposition 0.69 0.69 0

Wastewater 13.9 10.94 21%

Urban and Suburban Runoff

5.88 4.42 25%

Agricultural 18.05 13.59 25%

Septics 4.01 -0- 39%

TOTAL 49.53 2.46 21%

Source: US EPA Chesapeake Bay Program, 2010

Total Nitrogen Loads By Sector in the Maryland Portion of the Chesapeake Bay Watershed

Outline

OWTS BMP Expert Panel charge and membership

Baseline loadings from on-site systems

BMP definitions and qualifying conditions

Future research and management recommendations

OWTS Attenuation Expert Panel charge and membership

Progress and status

Frequently asked questions

Cost considerations

OWTS Panel Charge

Initially convened in January 2012

Review available science on the nitrogen removal performance of treatment practices

Provide concise definitions and percent reductions for nitrogen load reduction practices

Provide a definition for each treatment practice and the qualifying conditions under which credits can be received

Only address TN reduction in treatment technologies, not in the soil between edge-of-system and edge-of-stream (“attenuation”)

List of Panelists

Panelist Organization

Jim Anderson University of Minnesota

Eric Aschenbach Virginia Department of Health

Jason Baumgartner Delaware Department of Natural Resources and Environmental Control

Derrick Caruthers Delaware Department of Natural Resources and Environmental Control

Marcia Degen Virginia Department of Health

Kitt Farrell-Poe University of Arizona

Joshua Flatley Maryland Department of the Environment

Robert Goo U.S. Environmental Protection Agency

Rick Hertges West Virginia Health and Human Services

Mike Hoover North Carolina State University

Joyce Hudson U.S. Environmental Protection Agency

Randy Miles University of Missouri

Jeff Moeller Water Environment Research Foundation

Dave Montali West Virginia Department of Environmental Protection

Sushama Pradhan North Carolina State University

Jay Prager Maryland Department of the Environment

Other Authors and Contributors

Robert Adler – EPA Region 1

Jay Conta – Virginia Tech

Rich Piluk – Anne Arundel County Health Department

Staff/Contractor Support

Ning Zhou – Virginia Tech

Jeremy Hanson – Chesapeake Research Consortium

Victor D’Amato, Jim Kreissl, Mark Sievers – Tetra Tech

Baseline Load – Current Model

4 kg TN/person/year at edge-of-drainfield

• Assumed flow of 75 gpcpd

• TN concentration of 39 mg/L in septic tank effluent (STE)

60 percent attenuation between drainfield and edge-of-stream

Three BMPs

• Connection to central sewer (100 percent reduction from on-site sector)

• 50 percent denitrification system (50 percent reduction)

• Routine septic tank pump-out (5 percent reduction)

Baseline Load Recommendations

5 kg TN/person/year in raw wastewater and STE

• Assumed flow of 60 gpcpd

• TN concentration of 60 mg/L in septic tank effluent (STE)

4 kg TN/person/year at edge-of-drainfield

• 20 percent reduction in drainfield, average

No attenuation recommendation

Baseline Load Recommendations

Baseline System

Systems with BMPs

Exsitu BMP

• BMP efficiency assessed at end of process prior to soil application

• Reduction based on baseline effluent TN of 5 kg/person/year

Insitu BMP

• Reduction based on TN removal beyond baseline 20 percent reduction or 4 kg/person/year at edge-of-drainfield

Combined Insitu and Exsitu BMPs

• Reduction based on TN of 4 kg/person/year at edge-of-drainfield

• Assume consistent TN reduction across the soil treatment system, regardless of exsitu effluent characteristics

Best Management Practices

Exsitu (or pretreatment) system components

NSF Standard 40 Class I secondary systems

Intermittent (single-pass) media filters

Constructed wetlands (vegetated submerged beds)

Recirculating media filters (RMFs)

Anne Arundel County Integrated Fixed-Film Activated Sludge (IFAS)

Proprietary ex situ treatment systems

Insitu (soil treatment) system components

Shallow-placed, pressure-dosed dispersal

Elevated sand mounds

Permeable reactive barriers

Residential System with BMP

System with Exsitu BMP

Best Management Practices

Performance of recommended BMPs is well-supported by science and verifiable data • Ongoing sampling and analysis for each system is not recommended

for verification

Recommendations intended to complement existing state regulations and policies • Design and management criteria, beyond minimum standards

• Large/non-residential systems

Recognition that biological nitrogen removal performance can be variable • Encourage minimum USEPA Level 2 management model (operators,

permits)

• Suggestions for overarching management activities to promote effective BNR

Best Management Practices

Proprietary BMPs • Developed, marketed, and constructed by a manufacturer

• Manufacturer responsibility for system design, installation, and ongoing management

• Standardized design and construction and little variability between the same model

• Recommend two-step credit assignment protocol: provisional testing (e.g., NSF Standard 245) followed by third-party field testing

• TN reduction credit of 50 percent, unless managed according to min. EPA Level 3

Nonproprietary BMPs • Designed on case-by-case basis for each site using nonspecific and

readily available materials and mechanical equipment

• Local design and material variations common

• Two-step protocol for new systems goes through WWTWG

BMP Report Outline/TOC

Exsitu BMP Summary

Best Management Practice Qualifying Conditions

Ex Situ Reduction

Credit1

Septic tank (baseline practice)

N/A 0

NSF 40 Class I Equivalent Secondary Systems

Certified as Class I under NSF International Standard 40 or equivalent (e.g., CAN/BNQ 3680-600, CEN Standard 12566-3)

Design, installation, and operation in accordance with manufacturer recommendations and state or local regulation

20%

Intermittent media filters Timer-based flow equalization with 12–24 doses/day

2’ depth media ES = 0.5-1.0 mm; UC ≤ 4.0; < 0.5% passing #200 sieve

HLR ≤ 2 gpd/sf

OLR ≤ 5 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

20%

Constructed wetlands 2’ depth media ES = 40–80 mm inlet/outlet; ES = 20–30 mm treatment zone

OLR ≤ 1.2 lb BOD5/1000 sf-day; SA ≥ 54 sf/PE

Length ≥ 50 ft

Outlet structure for variable flooding depth

6” top layer of planting media

20%

RMF Timer-based flow equalization with 24–48 doses/d

2’ depth media

Sand media: ES = 1.0–5.0 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 5 gpd/sf; OLR ≤ 5 lb BOD/1000 sf

Gravel media: ES = 5.0–20 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 15 gpd/sf; OLR ≤ 15 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

Device capable of recirculating 3–5 times forward flow back to anoxic zone

50%

Anne Arundel County IFAS

2-day HRT anoxic chamber

1-day HRT aerobic chamber with ≥ 600 sf surface area fixed-film media

Aeration device capable of maintaining 3.0 mg/L DO

Device capable of recirculating ≥ 3 times forward flow back to anoxic zone

Alarm for aeration device fault

50%

Proprietary treatment systems

NSF Standard 245 certification

Technology-specific

Percent removal based on qualifying third-party testing

≥ 50%

Exsitu BMPs

Exsitu BMP Summary

Best Management Practice Qualifying Conditions

Ex Situ Reduction

Credit1

Septic tank (baseline practice)

N/A 0

NSF 40 Class I Equivalent Secondary Systems

Certified as Class I under NSF International Standard 40 or equivalent (e.g., CAN/BNQ 3680-600, CEN Standard 12566-3)

Design, installation, and operation in accordance with manufacturer recommendations and state or local regulation

20%

Intermittent media filters Timer-based flow equalization with 12–24 doses/day

2’ depth media ES = 0.5-1.0 mm; UC ≤ 4.0; < 0.5% passing #200 sieve

HLR ≤ 2 gpd/sf

OLR ≤ 5 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

20%

Constructed wetlands 2’ depth media ES = 40–80 mm inlet/outlet; ES = 20–30 mm treatment zone

OLR ≤ 1.2 lb BOD5/1000 sf-day; SA ≥ 54 sf/PE

Length ≥ 50 ft

Outlet structure for variable flooding depth

6” top layer of planting media

20%

RMF Timer-based flow equalization with 24–48 doses/d

2’ depth media

Sand media: ES = 1.0–5.0 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 5 gpd/sf; OLR ≤ 5 lb BOD/1000 sf

Gravel media: ES = 5.0–20 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 15 gpd/sf; OLR ≤ 15 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

Device capable of recirculating 3–5 times forward flow back to anoxic zone

50%

Anne Arundel County IFAS

2-day HRT anoxic chamber

1-day HRT aerobic chamber with ≥ 600 sf surface area fixed-film media

Aeration device capable of maintaining 3.0 mg/L DO

Device capable of recirculating ≥ 3 times forward flow back to anoxic zone

Alarm for aeration device fault

50%

Proprietary treatment systems

NSF Standard 245 certification

Technology-specific

Percent removal based on qualifying third-party testing

≥ 50%

Best Management Practice Qualifying Conditions

Ex Situ Reduction

Credit1

Septic tank (baseline practice)

N/A 0

NSF 40 Class I Equivalent Secondary Systems

Certified as Class I under NSF International Standard 40 or equivalent (e.g., CAN/BNQ 3680-600, CEN Standard 12566-3)

Design, installation, and operation in accordance with manufacturer recommendations and state or local regulation

20%

Intermittent media filters Timer-based flow equalization with 12–24 doses/day

2’ depth media ES = 0.5-1.0 mm; UC ≤ 4.0; < 0.5% passing #200 sieve

HLR ≤ 2 gpd/sf

OLR ≤ 5 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

20%

Constructed wetlands 2’ depth media ES = 40–80 mm inlet/outlet; ES = 20–30 mm treatment zone

OLR ≤ 1.2 lb BOD5/1000 sf-day; SA ≥ 54 sf/PE

Length ≥ 50 ft

Outlet structure for variable flooding depth

6” top layer of planting media

20%

RMF Timer-based flow equalization with 24–48 doses/d

2’ depth media

Sand media: ES = 1.0–5.0 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 5 gpd/sf; OLR ≤ 5 lb BOD/1000 sf

Gravel media: ES = 5.0–20 mm; UC ≤ 2.5; < 0.5% passing #200 sieve; HLR ≤ 15 gpd/sf; OLR ≤ 15 lb BOD/1000 sf

Uniform, pressurized distribution ≤ 6 sf/orifice

Device capable of recirculating 3–5 times forward flow back to anoxic zone

50%

Anne Arundel County IFAS

2-day HRT anoxic chamber

1-day HRT aerobic chamber with ≥ 600 sf surface area fixed-film media

Aeration device capable of maintaining 3.0 mg/L DO

Device capable of recirculating ≥ 3 times forward flow back to anoxic zone

Alarm for aeration device fault

50%

Proprietary treatment systems

NSF Standard 245 certification

Technology-specific

Percent removal based on qualifying third-party testing

≥ 50%

Exsitu BMPs

Exsitu BMPs

Insitu BMP Summary

Best Management Practice Qualifying Conditions

In Situ Reduction

Credit1

Conventional system (baseline practice)

N/A 20%

Shallow-placed, pressure-dosed dispersal

Drip or LPD within 12” of grade in A or A/B horizon

Credit not provided for sand or loamy sand soils

Lines placed on contour

Drip requires: prefiltration system, automatic flush cycle, flow equalization, air release valves

LPD requires: working pressure head of 2–5’, dosing volume of 7–10 times distribution system piping, lateral flushing provisions, max flow variation of 10% for each lateral

50%

Elevated sand mounds

Installation within intact A or A/B horizon

Credit not provided for sand or loamy sand surface soils under mound

Scarify surface of soil under mound

Uniform, pressurized distribution ≤ 6 sf/orifice

1–2’ layer of sand: ASTM C33; ≤ 20% by weight > 2 mm; D10 = 0.15 to 0.3 mm; UC = 4 to 6

Max. top of sand ALR = 1 gpd/sf for STE, 2 gpd/sf for secondary

6–12” loamy surface layer

50%

Permeable reactive barriers

Site-specific Case-by-case

Insitu BMPs

41

Combined Exsitu and Insitu BMPs

In Situ Practice

Ex Situ Practice Conventional

Baseline Shallow, Pressure

Dosed Elevated Mound

Septic tank baseline 4.0 kg/p/yr (0%) 2.5 kg/p/yr (38%) 2.5 kg/p/yr (38%)

NSF 40 Class I Secondary Systems 3.2 kg/p/yr (20%) 2.0 kg/p/yr (50%) 2.0 kg/p/yr (50%)

Intermittent Media Filter 3.2 kg/p/yr (20%) 2.0 kg/p/yr (50%) 2.0 kg/p/yr (50%)

Vegetated Submerged Bed 3.2 kg/p/yr (20%) 2.0 kg/p/yr (50%) 2.0 kg/p/yr (50%)

Anne Arundel Co. IFAS 2.0 kg/p/yr (50%) 1.25 kg/p/yr (69%) 1.25 kg/p/yr (69%)

Recirculating Media Filter 2.0 kg/p/yr (50%) 1.25 kg/p/yr (69%) 1.25 kg/p/yr (69%)

Research and Management Recommendations

Alkalinity control

• Critical for effective nitrification (50 mg/L recommended in final effluent)

• R&D for simple, inexpensive alkalinity control would help optimize TN removal and could justify higher credits in future

BMP sampling

• Not recommended to be mandatory for verification

• However, widespread BMP implementation offers opportunity for data collection

Data sharing and reciprocity

• EPA-OWM offered to facilitate

• Also addressed at July 2013 SORA/NEHA conference

Variable baseline and BMP performance by soil type

• Consider including soil type as predictor of TN reduction performance

• Defer to future attenuation expert panel

Attenuation Panel Charge

This is what we

care about!

Attenuation

Attenuation Panel Charge

Review science on how to factor attenuation of N and P

into TMDL onsite system load estimates.

● Can model can be improved by using attenuation rates that vary?

● Is 100% removal of total phosphorus (TP) from onsite wastewater system effluents warranted?

● Recommend a methodology and specific attenuation rates to be used in different contexts.

Also:

● Document data needs.

● Recommend procedures for reporting, tracking and verifying.

● Critically analyze any unintended consequences.

Member Classification

Name Organization Alternates Member Type Org. Type

Jason Baumgartner Delaware Derek Caruthers, Jack Hayes Voting ChesBay State Government

Jay Prager Maryland DEP Barry Glotfelty Voting ChesBay State Government

Tom Boekeloo New York DEP Voting ChesBay State Government

John Diehl PA DEP Nick Hong Voting ChesBay State Government

Marcia Degen Virginia DOH Eric Aschenbach, Jay Conta Voting ChesBay State Government

Dave Montali West Virginia Rick Hertges Voting ChesBay State Government

Robert Siegrist Colorado School of Mines Voting Academia

Michael O'Driscoll East Carolina University Charlie Humphreys Voting Academia

David Lindbo North Carolina State U Voting Academia

Jim Anderson University of Minnesota Voting Academia

Randy Miles University of Missouri Voting Academia

Carol Ptacek University of Waterloo Voting Academia

John Galbraith Virginia Tech Voting Academia

Durrelle Scott Virginia Tech Voting Academia

Kang Xia Virginia Tech Voting Academia

Eberhard Roeder Florida DOH Elke Ursin Voting State Government (other)

A.J. Maupin Idaho DEQ Voting State Government (other)

Sushama Pradhan NC Onsite Water Protection Steven Berkowitz Voting State Government (other)

Joyce Hudson US EPA - OWM Maureen Tooke Voting EPA

Robert Goo US EPA - OWOW Voting EPA

Rob Adler US EPA - Region 1 Voting EPA

Paul Finnell USDA Voting Federal Government (other)

Judy Denver USGS Voting Federal Government (other)

George Heufelder Barnstable County DHE Voting County Government (other)

David Sample Virginia Tech Advisory Academia, representative from the STAC

Rich Piluk Anne Arundel Co. HD Advisory ChesBay Local Government

Jeff Moeller WERF Guest Research Foundation

Lewis Linker Bay Program Office Advisory EPA, representative from the CBP modeling team

Ning Zhou Bay Program Office Advisory CBPO, representative from the WWTWG

David Wood Bay Program Office Supporting CBPO

Victor D'Amato Tetra Tech Supporting Consultant

Jim Kreissl Tetra Tech Supporting Consultant

Appointing a Chair

Responsibilities:

● Leader of panel

● Point of contact with Coordinator

● Help Coordinate

– Assign responsibilities

– Manage comment process

– Brief WWTWG

– Respond to comments

– Resolve issues

Multiple nominees (most declined)

Chair: Dr. David Lindbo

● NC State University Soil Science/Exension

● Specialty: Soil-Environment Relations

Activities to Date

Administration and orientation

White paper development/background discussions

Literature collection/dissemination

Six conference calls

● Lew Linker presentation on Bay model

● Bob Siegrist presentation on STUMOD

Developed draft report outline

● Use to assign/synthesize/summarize literature

● Start writing based on calls, etc.

Attenuation Panel Considerations/Issues

Variable as a function of soil characteristics

● Soil type

● Soil depth

● Soil geochemistry (redox conditions, labile carbon)

Variable as a function of topography

● Setback distance

● Riparian areas or wetlands in flow path

Variable as a function of effluent characteristics

● STE versus pre-treated

Nitrogen and phosphorus or just nitrogen?

White Paper - Attenuation Accounting Methodologies

Watershed Constant: single, average attenuation rate is used across the entire Bay watershed.

Subwatershed Constant: Different average attenuation rates assigned to different subwatersheds.

Spatially Variable: Attenuation rates assigned to different areas based on their spatial characteristics.

Site-Specific: Attenuation rates customized for individual systems, based on characteristics and location.

September 17 Conference Call

Maryland Maps – from Paul Finnell (USDA)

Report Outline

Introduction

● Historical approach

● Maryland (and others) approach

● Proposed geomorphic approach

● Challenges

Methods

● Describe weight of evidence approach

● Literature

● Modeling

● Hydrogeomorphology

Results and Discussion

● Coastal Plain

● Piedmont

● Ridge and Valley

● Appalachian Highlands

Conclusions and Recommendations

Future Activities

Refine draft outline (Nov-Dec)

Assign/review literature (Nov-Feb)

Internal draft report (Feb-Apr)

Draft report to WWTWG (Apr-May)

Additional review/revision

Frequently Asked Questions

If shallow, pressure dosed drainfields provide 50% reduction of TN, then why are they only credited with a 38% reduction.

● Shallow pressure dosed drainfields reduce STE from 5.0 kg/c/yr to 2.5 kg/c/yr (50% reduction).

● However, the edge of drainfield TN of 2.5 kg/c/yr needs to be compared with that for the baseline system – a conventional drainfield which achieves a 20% reduction to 4.0 kg/c/yr.

● 2.5 kg/c/yr I 4.0 kg/c/yr = 38%

Frequently Asked Questions

Will BMP performance vary based on soil or other site-specific characteristics?

● Possibly. This is mainly going to be addressed by the attenuation panel.

● We did exclude sands and loamy sands from receiving insitu BMP credits, but otherwise, no variability based on receiving soil type.

● Soil treatment unit performance may vary based on the quality of the effluent being applied.

Frequently Asked Questions

What about malfunctioning systems or large/non-residential systems?

● These have not be separately/specifically addressed by the panels.

● Current Bay model already factors malfunctions into “average” performance assumptions.

● Large/non-residential systems are somewhat covered by the existing model methodology that uses census tract population to estimate loads.

● Improving identification and improvement of malfunctioning systems may provide significant water quality benefits.

Frequently Asked Questions

“How much does it cost?”

System Installation Electrical O&M 60-yr PV LCC

Septic tank $3,500

($2,800-4,200)

0 $90

($70-110)

$6,700

($5,400-8,000)

Activated Sludge $9,000

($8,000-10,000)

$100

($80-120)

$560

($450-670)

$33,500

($27,000-40,000)

RMF $16,500

($13,000-20,000)

$10

($8-12)

$750

($600-900)

$43,500

($35,000-52,000)

Conventional $5,750

($4,600-6,900)

0 $300

($200-400)

$16,500

($15,000-18,000)

LPP $11,500

($9,000-14,000)

$25

($20-30)

$670

($540-800)

$36,000

($29,000-43,000)

Drip $10,150

($8,300-12,000)

$15

($12-18)

$620

($500-740)

$32,500

($26,000-39,000)

Incremental Costs $5,000-20,000

From: www.werf.org/decentralizedcost

Frequently Asked Questions – Costs for Improved Management

Mgt. Indicators

● parcel size

● proximity to collection systems

● proximity to large parcels

Questions

Photo Credit: Residential Application of a Vegetative Tertiary Filter by WetlandsPacific Corporation in Vancouver, British Columbia

Webcast Resources

• Recommendations of the On-Site Wastewater Treatment Systems Nitrogen Reduction Technology Expert Review Panel

• Technical Appendix G: Requirements to Enter Advanced On-Site Wastewater Treatment Practices into Scenario Builder and the Phase 5.3.2 Watershed Model

• Appendix A: List of Resources for Making Informed On-Site Wastewater Technology Decisions

www.chesapeakestormwater.net

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Remaining 2014 Webcasts

http://chesapeakestormwater.net/events/categories/2014-webcast-series/

Thursdays @ 12:00 EST

• December 2: Meeting the Chesapeake Bay Restoration

Requirements for Industrial Sites in MD

• December 4: Verification Simplified! Urban BMP

Verification for Local Governments

• December 11: The Best Urban BMP in the Bay Award!