Wastewater 101: Decentralized approach, community process, and options

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Information about Wastewater 101: Decentralized approach, community process, and options
Education

Published on November 26, 2008

Author: dmalchow

Source: slideshare.net

Description

General presentation to deliver basic septic system information to Minnesota homeowners.

Note to Reviewers: This Wastewater 101 Power Point presentation, much of which I developed, is what is typically used with community leaders and community members at an early meeting with a Small Community Wastewater Education Program (SCWEP) educator. The presentation is usually tailored to meet a community’s specific needs. In addition, I have attached another presentation, beginning with slide 67, that shows that the SCWEP is capable of delivering numerous in depth presentations on a variety of topics discussed in this presentation.

Overview of the Decentralized Approach, the Community Process, and Onsite Treatment Options

    Doug Malchow University of Minnesota Extension Service Educator (507) 280-5575 [email_address] Education and Outreach Coordinator - SMWI Valerie Prax University of Minnesota Extension Service Educator 888-241-5054 #3 [email_address] For more information http://septic.umn.edu Click on “Information for Small Communities”

Please turn off or silence your cell phone Thanks!

Professional Training – Designers, Inspectors, Pumpers, Installers Research and Demonstration Homeowner Operation & Maintenance Small Community Wastewater Education Program

Professional Training – Designers, Inspectors, Pumpers, Installers

Research and Demonstration

Homeowner Operation & Maintenance

Small Community Wastewater Education Program

Criteria for Selecting a Treatment system Treatment – protect health & environment Life-cycle costs - installation, operation, maintenance, repairs, monitoring, replacement Sustainability Appearance Reliability Ease of management Space requirement Flexibility Community values and culture Consistent with land use plan

Treatment – protect health & environment

Life-cycle costs - installation, operation, maintenance, repairs, monitoring, replacement

Sustainability

Appearance

Reliability

Ease of management

Space requirement

Flexibility

Community values and culture

Consistent with land use plan

Sewage Treatment Options Three Approaches to Wastewater Treatment Conducting a Complete Assessment Community Process for Making Wastewater Treatment Decisions

Three Approaches to Wastewater Treatment

Conducting a Complete Assessment

Community Process for Making Wastewater Treatment Decisions

Three approaches to wastewater treatment 1) Centralized: Collection network (many homes) Central treatment facility(ies) Discharge - surface 2) Decentralized: Individual or small group of homes On-site treatment facilities (near site) Discharge – subsurface 3) Combination

1) Centralized:

Collection network (many homes)

Central treatment facility(ies)

Discharge - surface

2) Decentralized:

Individual or small group of homes

On-site treatment facilities (near site)

Discharge – subsurface

3) Combination

What Type of Treatment is Best for Your Community? You decide Explore all of the options You guide the process Make the decision with community input Decide on a treatment option that includes all costs: short term (construction), mid-term (management), and long-term (replacement)

You decide

Explore all of the options

You guide the process

Make the decision with community input

Decide on a treatment option that includes all costs: short term (construction), mid-term (management), and long-term (replacement)

 

Centralized approach Collection: pipes - gravity, pressure, vacuum (combinations) Treatment: screens, clarifiers, trickling filters, biological contactors, activated sludge, stabilization ponds, tertiary treatment, & stream purification Functions: remove solids, decompose organic solids, destroy pathogens, remove nutrients

Collection: pipes - gravity, pressure, vacuum (combinations)

Treatment: screens, clarifiers, trickling filters, biological contactors, activated sludge, stabilization ponds, tertiary treatment, & stream purification

Functions: remove solids, decompose organic solids, destroy pathogens, remove nutrients

Collection Treatment

Centralized Collection & treatment Surface discharge EPA discharge limits*: BOD – 25mg/l TSS – 30mg/l Fecal Coliform – 200 org colonies/100ml Only applies March-Nov Phosphorous – 1mg/l Nitrogen – no limit (no ammonia) *MPCA “NPDES/SDS Permits” Fact Sheet – Feb 1998

Collection & treatment

Surface discharge

EPA discharge limits*:

BOD – 25mg/l

TSS – 30mg/l

Fecal Coliform – 200

org colonies/100ml

Only applies March-Nov

Phosphorous – 1mg/l

Nitrogen – no limit (no ammonia)

*MPCA “NPDES/SDS Permits” Fact Sheet – Feb 1998

Q: Do centralized systems ever fail to properly treat wastewater? A: Yes , Why/How? Design/construction - type chosen, breaks, infiltration/exfiltration - “leaks” in & out, “by-passes” Over loading “ Bad” things down the drain Improper maintenance - skills & money Discharged water is not drinking water quality

A: Yes , Why/How?

Design/construction - type chosen, breaks, infiltration/exfiltration - “leaks” in & out, “by-passes”

Over loading

“ Bad” things down the drain

Improper maintenance - skills & money

Discharged water is not drinking water quality

Anatomy of a Septic System Plumbing : wastewater collection Septic tank : primary treatment Soil treatment system : final treatment and dispersal

Plumbing : wastewater collection

Septic tank : primary treatment

Soil treatment

system : final treatment and dispersal

EPA: “Decentralized approach will work” In 1997, EPA suggested ‘decentralized’ systems as a solution to many sewage treatment problems Why? Now have good on-site treatment systems Cost is usually lower than centralized Report: www.epa.gov/ow-owm.html/decent/index

In 1997, EPA suggested ‘decentralized’ systems as a solution to many sewage treatment problems

Why?

Now have good on-site treatment systems

Cost is usually lower than centralized

Report:

www.epa.gov/ow-owm.html/decent/index

Decentralized systems: Individual or multi-household (cluster) Standard - trenches, mounds, at-grades Alternative Systems- pre-treatment final treatment/dispersal separation Water supply options

Individual or multi-household (cluster)

Standard - trenches, mounds, at-grades

Alternative Systems-

pre-treatment

final treatment/dispersal

separation

Water supply options

Determining ‘decentralized’ feasibility Typical assessment: Compliant Non-compliant More complete assessment: Compliant ‘ Could be’ Compliant ‘ Can’t be’ Compliant

Typical assessment:

Compliant

Non-compliant

More complete assessment:

Compliant

‘ Could be’ Compliant

‘ Can’t be’ Compliant

Conducting a more complete assessment Map of parcels Records: Permits Age of systems Maintenance Identify: Likely compliant Spot check Properties to be checked: No records Older than XX years Suspected problems Map of findings Well location Property boundaries Setbacks Other (Soils, ?)

Map of parcels

Records:

Permits

Age of systems

Maintenance

Identify:

Likely compliant

Spot check

Properties to be checked:

No records

Older than XX years

Suspected problems

Map of findings

Well location

Property boundaries

Setbacks

Other (Soils, ?)

Comply (10) Don’t Comply (25) Minnesota Lake 35 parcels Typical Assessment

Comply (10) Can’t Comply (10) Could Comply (15) Minnesota Lake 35 parcels More Complete Assessment

Comply (10) Don’t Comply (25) Minnesota Lake 35 parcels Typical Assessment w/Central Treatment Cost to Community $15,000 per parcel Total Cost = $ 525,000

Comply (10) Can’t Comply (10) Could Comply (15) Minnesota Lake 35 parcels Complete Assessment w/Decentralized Treatment Cost to Community 10 x $0 =0 15 x $10,000 = $150,000 10 x $15,000 = $150,000 Total Cost = $300,000

Typical Cost Range per Connection in Low Density Areas Design & Installation: Decentralized $8000 to $20,000 Centralized $20,000 to $40,000+

Design & Installation:

Decentralized

$8000 to $20,000

Centralized

$20,000 to $40,000+

Jefferson German Septic Status Green= ’96/later Red= pre-’96 White= no record

Small Community: Communities not currently served by centralized systems - “unsewered” Include: incorporated unincorporated villages shore lands ‘ groups of homes’

Communities not currently served by centralized systems - “unsewered”

Include:

incorporated

unincorporated

villages

shore lands

‘ groups of homes’

What might be ‘unique’ about these small communities? Small lots Low overall density (perimeter of a lake) Poor Soils Especially valuable natural resource (I.e. lake, river) Mix of seasonal & full-time residents Growing or decreasing population Income levels

Small lots

Low overall density (perimeter of a lake)

Poor Soils

Especially valuable natural resource (I.e. lake, river)

Mix of seasonal & full-time residents

Growing or decreasing population

Income levels

How is wastewater currently being handled in ‘unsewered’ areas? On-site Disposal pipe to ditch/lake non-compliant system other? On-site Treatment compliant system

On-site Disposal

pipe to ditch/lake

non-compliant system

other?

On-site Treatment

compliant system

Characteristics of Successful Communities Understand current situation clearly before looking at possible solutions Use the ‘civic engagement’ model to involve diverse interests/views from the community Have or develop effective leadership from within the community

Understand current situation clearly before looking at possible solutions

Use the ‘civic engagement’ model to involve diverse interests/views from the community

Have or develop effective leadership from within the community

Characteristics continued... Recognize the bias’s and self-interests of professionals they’re working with Defines an appropriate goal and boundaries Identify and examine all options Keep all affected parties informed

Recognize the bias’s and self-interests of professionals they’re working with

Defines an appropriate goal and boundaries

Identify and examine all options

Keep all affected parties informed

Success or failure? Success or failure in finding a viable solution is frequently more dependent on a sound community process than on the availability of treatment options and financing!

Success or failure in finding a viable solution is frequently more dependent on a sound community process than on the availability of treatment options and financing!

Exploring Small Community Wastewater Treatment Treatment Options Management Community Structures Costs & Financing

Treatment Options

Management

Community Structures

Costs & Financing

Form a Task Force Wide range of interests Citizens and local leaders Provides leadership for process Oversees the process (i.e. gathers information, point of contact) Shares information with stakeholders (especially residents)

Wide range of interests

Citizens and local leaders

Provides leadership for process

Oversees the process (i.e. gathers information, point of contact)

Shares information with stakeholders (especially residents)

Develop a Community Vision for Treatment Socially acceptable Cost effective Provides viable Treatment option(s)

Socially acceptable

Cost effective

Provides viable

Treatment option(s)

Down the Road... 3. Develop work plan 4. Keep citizens informed 5. Gather and evaluate information 6. Keep citizens informed

3. Develop work plan

4. Keep citizens informed

5. Gather and evaluate information

6. Keep citizens informed

Establish Appropriate Boundaries

Failing Communities Use small groups to make decisions and expect everyone to agree (and pay the bill!) Let engineers, government, consultants, and funding sources dictate their choices.

Use small groups to make decisions and expect everyone to agree (and pay the bill!)

Let engineers, government, consultants, and funding sources dictate their choices.

This is not supposed to be easy Everyone may not agree Only representation of all affected parties and diversity of perspectives ensure success The Struggle is the Means to the End

This is not supposed to be easy

Everyone may not agree

Only representation of all affected parties and diversity of perspectives ensure success

Onsite Treatment Options: An Introduction

Anatomy of a Septic System Plumbing : wastewater collection Septic tank : primary treatment Soil treatment system : final treatment and dispersal

Plumbing : wastewater collection

Septic tank : primary treatment

Soil treatment

system : final treatment and dispersal

 

Septic Tank: Primary Treatment Job of tank: catch the solids Decompose organic solids Store inorganic solids Components : Water tight tank, inlet, inlet baffle, inspection pipes, manhole, outlet baffle, outlet pipe Typical temp in tank: 60 ° Layers in tank Scum layer: floating soap, grease, toilet paper, etc Liquid layer: water, liquid, and suspended solids Sludge: heavy organic and inorganic materials in the bottom of the tank Anaerobic bacteria breakdown organic solids

Job of tank: catch the solids

Decompose organic solids

Store inorganic solids

Components :

Water tight tank, inlet, inlet baffle, inspection pipes, manhole, outlet baffle, outlet pipe

Typical temp in tank: 60 °

Layers in tank

Scum layer: floating soap, grease, toilet paper, etc

Liquid layer: water, liquid, and suspended solids

Sludge: heavy organic and inorganic materials in the bottom of the tank

Anaerobic bacteria breakdown organic solids

System Components Source Tank Drainfield Treatment in Soil Confining layer/Saturated Zone Well 3 feet

Mound System Confining layer/Saturated Zone Drainlines and Gravel Topsoil Sand 3 feet Treatment in Soil

Outdoor toilets Allowed under state rules. If earth bottom pit, 3 feet of unsaturated soil required. If 3 feet not available, the pit must be “liquid tight”. Wastes periodically pumped.

Allowed under state rules.

If earth bottom pit, 3 feet of unsaturated soil required.

If 3 feet not available, the pit must be “liquid tight”. Wastes periodically pumped.

Holding tanks Must be approved by local government. At least 1,000 gals or 400 gals x no. of bedrooms (greater of the two) Require frequent pumping, reported to local government. Require water use monitoring

Must be approved by local government.

At least 1,000 gals or 400 gals x no. of bedrooms (greater of the two)

Require frequent pumping, reported to local government.

Require water use monitoring

Separation Technology Incinerator Toilets - Eliminates toilet wastes. Expensive ($800-$1500), requires “cool down”, waste gases may smell Chemical Toilets – Wastes reduced to 2% w/ little maintenance. Waste goes to tank, cost $200-$700 plus 3 cents per flush. Composting Toilets – No water used nor plumbing required. Evaporate water, compost solids; requires electricity for heat, fans, mixers; periodic compost removal; cost $750-$3,000.

Incinerator Toilets - Eliminates

toilet wastes. Expensive ($800-$1500), requires “cool down”, waste gases may smell

Chemical Toilets – Wastes reduced to 2% w/ little maintenance. Waste goes to tank, cost $200-$700 plus 3 cents per flush.

Composting Toilets – No water used nor plumbing required. Evaporate water, compost solids; requires electricity for heat, fans, mixers; periodic compost removal; cost $750-$3,000.

Separation Technology Greywater IS sewage and requires treatment Tank – water tight, 40% smaller than normal tank Soil Treatment – Final treatment, but can be 40% smaller than normal

Greywater IS sewage and

requires treatment

Tank – water tight, 40% smaller than normal tank

Soil Treatment – Final treatment, but can be 40% smaller than normal

Alternatives - Pretreatment for soils

Advanced Treatment System Components Source Septic Tank Drainfield Soil Pump Tank Filter

Aerobic Treatment Unit Pretreats sewage by adding air to break down organics, reduce pathogens, transform nutrients better than conventional septic tanks Pros – 25 sq. ft. for 3 bedroom home, prolongs life of drainfield Cons – Requires maintenance, $200 to $500 to operate (electricity, pumping, repairs)

Pretreats sewage by adding air to break down organics, reduce pathogens, transform nutrients better than conventional septic tanks

Pros – 25 sq. ft. for 3 bedroom home, prolongs life of drainfield

Cons – Requires maintenance, $200 to $500 to operate (electricity, pumping, repairs)

Aerobic treatment units

 

Advanced or pre-treatment of septic effluent Water leaves advanced treatment unit as high quality effluent Soil treatment system better able to accept effluent, should last longer Useful for problematic sites (less than 3 feet of unsaturated soil, compacted, environmentally sensitive areas)

Water leaves advanced treatment unit as high quality effluent

Soil treatment system better able to accept effluent, should last longer

Useful for problematic sites (less than 3 feet of unsaturated soil, compacted, environmentally sensitive areas)

Sand Filter

Sand Filter Pros – Proven technology (30 years), reliable effluent treatment (BOD, fecal coliform), can be placed on any type of soil, sand can be replaced (5 years or more, low monthly cost (a few dollars) Cons –Not a good choice for small lots, high maintenance requirements over time.

Pros – Proven technology (30 years), reliable effluent treatment (BOD, fecal coliform), can be placed on any type of soil, sand can be replaced (5 years or more, low monthly cost (a few dollars)

Cons –Not a good choice for small lots, high maintenance requirements over time.

Re-circulating sand filter

Recirculating Sand Filter Pros – Proven technology, very clean effluent, can be placed on any type of soil, small size, low cost to run Cons – Require maintenance (flow meter, pumps, tank liner, media quality), top layer of media may plug

Pros – Proven technology, very clean effluent, can be placed on any type of soil, small size, low cost to run

Cons – Require maintenance (flow meter, pumps, tank liner, media quality), top layer of media may plug

Fabric/Textile Filter

 

Textile Filter Pros – Small size, proven technology, can be installed in any soil, low monthly cost to operate ($1 per month) Cons - Require maintenance (cleaning, repairs), could cost $200 to $500 per year

Pros – Small size, proven technology, can be installed in any soil, low monthly cost to operate ($1 per month)

Cons - Require maintenance (cleaning, repairs), could cost $200 to $500 per year

Peat Filter

 

 

Peat Filters Pretreats effluent by filtering through 2 feet of peat. Pros – Proven technology, peat can be easily replaced (10 to 15 years), low monthly cost ($1/month) Cons – Require maintenance (cleaning, repairs), could cost $200 to $500 per year

Pretreats effluent by filtering through 2 feet of peat.

Pros – Proven technology, peat can be easily replaced (10 to 15 years), low monthly cost ($1/month)

Cons – Require maintenance (cleaning, repairs), could cost $200 to $500 per year

Questions? http://septic.umn.edu (no www in front)

Note to Reviewers: The following, which I created, is a presentation geared toward the topic of choosing an appropriate community structure (if none exists). This is an example of a fleshed out topic that was mentioned in slide 26, but not discussed in detail, in the Wastewater 101 presentation. The SCWEP is capable of delivering numerous in depth presentations on a variety of topics mentioned in the Wastewater 101 presentation.

Options for Community Structures: Wastewater Treatment On-Site Sewage Treatment Program http://septic.umn.edu Extension Educators Doug Malchow 507-280-5575 [email_address] Valerie Prax 320-225-5054 [email_address]

Points to keep in mind: There are options for districts, but the public needs to be involved/informed all along the way For all the options legal council needs to be involved The MPCA only reviews the creation of Sanitary Districts under Minn.Stat. 115.19 to 115.20

There are options for districts, but the public needs to be involved/informed all along the way

For all the options legal council needs to be involved

The MPCA only reviews the creation of Sanitary Districts under Minn.Stat. 115.19 to 115.20

Why do we need a “community structure”? When multiple landowners work together a legal and responsible entity is usually needed to work on behalf of the community members.

When multiple landowners work together a legal and responsible entity is usually needed to work on behalf of the community members.

What roles might the entity play? Provide continuity within the project Acquire property or easements Obtain/administer financing to build project Negotiate contracts Develop and enforce project rules Recover costs of damages to the system Budget/Levy to manage, repair, and replace the system

Provide continuity within the project

Acquire property or easements

Obtain/administer financing to build project

Negotiate contracts

Develop and enforce project rules

Recover costs of damages to the system

Budget/Levy to manage, repair, and replace the system

Determine District Boundaries Based Upon Need Convince residents that they need improved wastewater treatment before drawing district boundaries Residents with complaint wastewater treatment systems included within a district’s boundaries may not support a new wastewater treatment system if it will cost them money

Convince residents that they need improved wastewater treatment before drawing district boundaries

Residents with complaint wastewater treatment systems included within a district’s boundaries may not support a new wastewater treatment system if it will cost them money

Comply Don’t Comply Minnesota Lake Typical Assessment

Comply Can’t Comply Could Comply Minnesota Lake More Complete Assessment

More complete assessment Offers a complete understanding of the current situation Basis to look at potential solutions Helps determine appropriate boundaries Fits with the proposed funding hierarchy changes

Offers a complete understanding of the current situation

Basis to look at potential solutions

Helps determine appropriate boundaries

Fits with the proposed funding hierarchy changes

Types of Entities that “could” Oversee a System Lake or homeowner associations Joint Exercise of Powers Agreements Lake Improvement Districts Sanitary (Sewer) Districts Subordinate Service Districts

Lake or homeowner associations

Joint Exercise of Powers Agreements

Lake Improvement Districts

Sanitary (Sewer) Districts

Subordinate Service Districts

Lake or Homeowner Associations Advantages: Early catalyst for action Provide some funding Educational network

Advantages:

Early catalyst for action

Provide some funding

Educational network

Lake or Homeowner Associations Disadvantages: Lack ability to levy for funds Fee collection difficulties Rules enforcement difficult Lack accountability to government entity

Disadvantages:

Lack ability to levy for funds

Fee collection difficulties

Rules enforcement difficult

Lack accountability to government entity

Joint Exercise of Powers Agreements Advantages: Allow issues that cross political boundaries to be addressed Agreements carefully spell out issue, powers and responsibilities

Advantages:

Allow issues that cross political boundaries to be addressed

Agreements carefully spell out issue, powers and responsibilities

Joint Exercise of Powers Agreements Disadvantages: Time consuming- appointed board; multiple hearings; carefully outlined and detailed agreement between multiple partners Any partner can withdraw, leaving remaining partners with obligations

Disadvantages:

Time consuming- appointed board; multiple hearings; carefully outlined and detailed agreement between multiple partners

Any partner can withdraw, leaving remaining partners with obligations

Lake Improvement Districts Advantages: Created by 26% of property owners within proposed area Focused on improving water quality

Advantages:

Created by 26% of property owners within proposed area

Focused on improving water quality

Disadvantages: County remains legal entity managing a small area; district can’t levy All county residents responsible financially Created by small number of residents Lake Improvement Districts

Disadvantages:

County remains legal entity managing a small area; district can’t levy

All county residents responsible financially

Created by small number of residents

Sanitary Districts Advantages: Independent commission may manage Can levy and bond Can write and enforce ordinances Some can provide water service (116 A)

Advantages:

Independent commission may manage

Can levy and bond

Can write and enforce ordinances

Some can provide water service

(116 A)

Disadvantages: Created by petition/hearing process by MPCA Boundaries and need established before petitioning MPCA Lengthy process Difficult to get consensus over large area Sanitary Districts

Disadvantages:

Created by petition/hearing process by MPCA

Boundaries and need established before petitioning MPCA

Lengthy process

Difficult to get consensus over large area

Subordinate Service Districts Advantages: Can be created at the county or township level Relatively easy/inexpensive to create in short time Costs borne only by users Can evolve easily over time as needs change

Advantages:

Can be created at the county or township level

Relatively easy/inexpensive to create in short time

Costs borne only by users

Can evolve easily over time as needs change

Township 365A Requires petition of 50% + 1 of property owners in contiguous area; signature verification Public hearing Board approves or disapproves Reverse referendum by 25% of property owners puts district on hold; special election with simple majority of those voting rules Can be enlarged Dissolved via petition of 75% of property owners in district followed by Board decision Subordinate Service Districts

Township 365A

Requires petition of 50% + 1 of property owners in contiguous area; signature verification

Public hearing

Board approves or disapproves

Reverse referendum by 25% of property owners

puts district on hold; special election with simple majority of those voting rules

Can be enlarged

Dissolved via petition of 75% of property owners in district followed by Board decision

County 375B – Creation by Resolution Following public hearing Can be withdrawn via resolution following public hearing Subordinate Service Districts

County 375B – Creation by Resolution

Following public hearing

Can be withdrawn via resolution following public hearing

County 375B – Creation by petition Subordinate Service Districts Requires petition of 10% of qualified tax voters in proposed contiguous area Public hearing Board approves or disapproves Reverse referendum by 5% of qualified tax voters in proposed area puts district on hold Special election majority of votes rules Withdrawal after petition by 10% of property owners followed by special election; majority rules

County 375B – Creation by petition

Requires petition of 10% of qualified tax voters in proposed contiguous area

Public hearing

Board approves or disapproves

Reverse referendum by 5% of qualified tax voters in proposed area puts district on hold

Special election majority of votes rules

Withdrawal after petition by 10% of property owners followed by special election; majority

rules

Questions? septic.umn.edu (Information for homeowners)

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