Decentralized Wastewater Treatment Systems

A Program Strategy

USEPA Office of Water

UNITED STATES

EN

VIRONMENTAL PROTECTION

AGENCY
Decentralized Wastewater Treatment Systems: A Program Strategy i

Decentralized wastewater treatment systems (commonly called septic systems) are a significant 

component of this nation’s wastewater infrastructure. They can be an effective option for 

protecting public health and the environment if properly designed, installed, and managed. 

They can be a significant threat to public health and the environment if they are not.

I am pleased to publish this Strategic Plan to improve the performance of decentralized 

wastewater treatment systems. This Strategic Plan presents our key goals and planned actions 

for our decentralized wastewater treatment system program. It builds on existing partnerships 

to provide a solid foundation of information, training, management, and oversight. It includes 

components for regulators, service providers, and property owners. I believe this Strategic Plan 

is a significant step forward for communities that choose a decentralized approach to help 

protect the health of their citizens and the environment.

A message from Ben Grumbles, 

Assistant Administrator of the Office of Water

“Proper septic system maintenance is a commonly overlooked 

responsibility. Failing systems are a significant threat to our health 

and our water quality. Property owners can save themselves a lot 

of money and trouble by following a few simple guidelines.”
ii Decentralized Wastewater Treatment Systems: A Program Strategy
Decentralized Wastewater Treatment Systems: A Program Strategy 1

EPA’S VISION

Decentralized wastewater treatment systems are appropriately managed, perform 

effectively, protect human health and the environment, and are a key component of 

our nation’s wastewater infrastructure.

EPA’S MISSION

EPA will provide national direction and support to improve the performance of 

decentralized systems by promoting the concept of continuous management and 

facilitating upgraded professional standards of practice.

STRATEGIC GOALS AND ACTIONS

This program strategy builds upon EPA’s 2003–2008 Agency Strategic Plan, which 

identifies septic systems as a source of pollution. The program strategy includes the 

principles and strategic goals that will guide EPA’s decentralized wastewater program 

over the next five years. To accomplish these goals, EPA will implement a series of 

actions internally and externally through partnerships with state and local governments 

and national organizations representing practitioners and the public (see Key Strategic 

Goals and Actions section).

This strategy presents EPA’s vision, 

mission and actions to improve the 

performance of decentralized wastewater 

treatment systems, thereby providing 

better protection of public health and 

water resources. 

Decentralized Wastewater Treatment Systems:

A Program Strategy
2 Decentralized Wastewater Treatment Systems: A Program Strategy

Scope

Decentralized wastewater systems, often called “septic” or “onsite” 

systems, derive their name from their location—they treat wastewater close to the source, typically providing treatment on the property 

of individual homes or businesses. Decentralized systems also 

include systems serving clusters of individual homes, large capacity 

septic systems, and small collection and treatment systems (including “package plants”). These systems similarly treat wastewater 

close to the source, typically using small pipes for collecting small 

volumes of domestic wastewater, unlike centralized urban wastewater treatment systems that pipe large amounts of wastewater many 

miles through sewers prior to reaching the treatment facility. 

Centralized wastewater treatment facilities typically discharge treated 

waste to surface streams, while decentralized systems (especially 

smaller ones) usually disperse treated waste under the ground 

surface, where the soil provides further treatment. Some decentralized systems are designed to discharge to surface waters following 

treatment, and these systems are also addressed in EPA’s program 

strategy.

Problem Statement

Decentralized systems are an issue of national concern. Based on current information, 

decentralized systems:

 Serve 25% of the U.S. populationa

 Are used in about one-third of all new housing and commercial developmenta

 Are typically utilized in rural areas, however, more than half of the 25 million 

systems are found in suburban areasa

Decentralized systems protect human health and water quality when they are properly 

sited, designed, installed, operated and maintained. However, it has been estimated that:

 Between 10 and 20% of all onsite systems are not adequately treating waste 

(actual failure rates are unknown); the failure rate for cluster systems which 

discharge is being researcheda,b

 Half are more than 30 years old, and more likely to malfunctiona

 Septic systems are the second greatest threat to groundwater qualityc

 (as 

viewed by State water quality agencies)

There is currently limited information to document health and water quality problems 

resulting from poorly designed, operated and maintained systems, partly due to their 

widely distributed nature. The amount of impact to groundwater and surface water 

a

 U.S. Department of Commerce, U.S. Census Bureau, American Housing Survey for the United States-1995, issued September 1997.

b V.I., Nelson, S.P. Dix, and F. Shephard, Advanced Onsite Wastewater Treatment and Management Scoping Study, May 1999.

c U.S. Environmental Protection Agency, National Water Quality Inventory: 1996 Report to Congress, EPA 841-R-97-008, 1998.
Decentralized Wastewater Treatment Systems: A Program Strategy 3

from sub-surface dispersal or surface-discharging decentralized systems is generally 

unknown. These impacts are currently being investigated by EPA.

While complete quantitative information is lacking, there are many examples of improperly functioning onsite and other decentralized wastewater systems contributing to 

water quality impairments. These types of wastewater systems have been identified as 

contributors to numerous water quality problems, including swimming beach closures, 

drinking water source impairments, and shellfish bed closures. 

This program strategy identifies how EPA will address water quality impacts by working 

with state and local regulators and other key stakeholders to upgrade the performance 

of decentralized systems through better management practices (siting, design, installation, permitting, inspections, operation and maintenance, etc.), as well as to upgrade 

professional standards in the decentralized wastewater industry. The strategy also specifies how the recommended management practices will be integrated in the activities and 

approaches being applied in the various EPA water programs, thereby helping to achieve 

mutual water quality objectives and public health protection goals.

Historical Background

The use of septic tanks for primary treatment of wastewater began in the late 1800s, 

and discharge of septic tank effluent into gravel-lined subsurface drains became a 

common practice during the middle of the 20th century. Public health departments 

were charged with enforcing the first onsite wastewater “disposal” laws, which were 

mostly based on soil percolation rates. During the 1950s, states began to adopt laws 

upgrading onsite system design and installation practices. Despite these improvements, 

many regulations are based on prescribed system designs that require site conditions to 

fit system capabilities rather than the reverse. The prevailing philosophy was based on 

the assumption that centralized wastewater collection and treatment services would be 

available in the future. The result was a wide variety of state and local regulations and 

codes controlling decentralized systems.

The 1970s saw an increase in research and 

technology development, creating a host of alternative decentralized systems capable of meeting 

secondary and advanced levels of treatment. 

However, the management of these systems 

(site evaluation, installation, operation and 

maintenance) remained at the pre-1970s level 

of sophistication, as did the levels of awareness and education of the property owner and 

regulator. As a result, many systems have been 

sited, designed, installed, operated and maintained based on outdated codes, regulations and 

information.
4 Decentralized Wastewater Treatment Systems: A Program Strategy

Findings - Report to Congress

In 1996, Congress directed EPA to develop a report addressing: (a) the ability of decentralized systems to make more efficient use of the limited funding available for wastewater infrastructure, (b) whether these systems were appropriate alternatives to centralized 

treatment, and if so, (c) what actions EPA would take to implement the alternatives. 

In April 1997, EPA developed its Response to Congress on Use of Decentralized 

Wastewater Treatment System”. In this document, EPA concluded that decentralized 

systems can protect public health and the environment, typically have lower capital and 

maintenance costs for rural communities, are appropriate for varying site conditions, and 

are suitable for ecologically sensitive areas when adequately managed. However, several 

major barriers to the improved performance of these systems were identified, including:

 Lack of awareness about system maintenance requirements, and public 

misperception regarding system performance and capability

 Regulatory and legal constraints

 Lack of management

 Fear of liability; financial disincentive for engineering consultants

 Financial constraints

Until significant progress toward eliminating these major barriers is made, it is likely that 

decentralized systems will continue to cause health and environmental problems, and 

will not be recognized as a key component of our nation’s long-term wastewater infrastructure. 

Stakeholder Involvement

A wide variety of stakeholders involved in regulating and servicing 

decentralized systems have expressed an interest in EPA involvement. This includes regulatory agencies at the Federal (USDA and 

HUD), state and tribal (health and environmental agencies), and 

local levels. Other stakeholders include service providers such as 

planners, developers, site evaluators, designers, operators, inspectors, manufacturers, pumpers and waste haulers. In addition, homeowners are increasingly interested in advice on proper maintenance 

and cost-effective solutions to wastewater issues.

EPA has initiated an extensive outreach program to obtain assistance in reaching the various stakeholders. Many stakeholders are represented by national organizations that have 

agreed to partner with EPA, including:

 State onsite regulators

 National Onsite Wastewater Recycling Association

 National Environmental Services Center

 National Environmental Health Association

 National Association of County Officials
Decentralized Wastewater Treatment Systems: A Program Strategy 5

 National Association of City and County Health Officials

 National Association of Towns and Townships

 Rural Community Assistance Partnership

 National Association of Waste Transporters

 Consortium of Institutes for Decentralized Wastewater Systems

 Water Environment Federation

Guiding Principles

The following principles will guide the efforts of EPA to ensure implementation of systems 

that protect public health and the environment:

 Protection of Public Health and the Environment. EPA supports the most 

sustainable approach to implementing protective water pollution control solutions 

whether it be centralized or decentralized. Where used, decentralized systems 

must provide protection of public health and the environment for their served 

communities. This applies equally regardless of the economic status, race or size of 

the community.

 Local Decision-making. The decision to implement a centralized or decentralized (or 

combination) solution to wastewater treatment needs is made at the local level. 

 Watershed-wide Integration. Integrated wastewater facility planning and 

management of water resources on a watershed level promotes sound and 

sustainable communities. The role of properly sited, designed, installed and managed 

decentralized systems that provide for recycling and reuse of treated wastewater 

for groundwater recharge, replenishment of aquifers and protection of ground and 

surface water, should be considered in planning.

 State, Tribal and Local Government Authority. States, Tribes and some local 

governments are responsible for regulating and managing decentralized systems. 

Flexibility is needed to craft and implement cost-effective management programs 

that are suitable for each individual community.

 Agency-wide Coordination. Most water programs have a role, either direct or 

indirect, in managing or working with decentralized systems. In dealing with 

decentralized systems, all water programs should facilitate improved siting, design, 

installation and management that protect human health and the environment. 

Agency programs (including point source, non-point source, groundwater, and 

funding programs) should regularly coordinate on issues that affect decentralized 

systems.

 Cost Effectiveness. Implementation of this strategy will provide for a broader 

range of cost effective options for communities to consider in meeting their needs, 

particularly in those communities that are less densely populated.
6 Decentralized Wastewater Treatment Systems: A Program Strategy

 Partnerships. Implementation of this strategy will depend on voluntary partnerships 

with States/Tribes, local governments, service providers and other stakeholders. 

 Targeted Efforts. Given the wide variety of barriers to address, implementation of 

this strategy will focus on those activities that produce the greatest environmental 

and public health benefit.

Key Strategic Goals and Actions

 Strategic Goal #1: Strengthened internal and external partnerships

Action 1: Develop action plans in each Regional office to address Regional 

and watershed-specific activities to support the Program 

Strategy. Hold annual meetings of EPA coordinators.

Action 2: Conduct forums in each Regional office to promote collaboration 

between regional, state and local regulators.

Action 3: Develop a Memorandum of Understanding with external partners 

to solidify their support for the program.

Action 4: Identify and pursue opportunities for improved coordination 

among water programs (point source, non-point source, estuaries, watersheds, water quality cooperative agreements, source 

water assessment and protection, UIC, TMDL).
Decentralized Wastewater Treatment Systems: A Program Strategy 7

 Strategic Goal #2: Improved system performance through improved practitioner 

competency, management practices, and technology transfer.

Action 1: EPA, working with the stakeholders, will publish a Management 

Handbook and other tools that serve as implementation guidance 

for the Management Guidelines.

Action 2: Provide assistance in upgrading training, registration, certification and licensing programs for practitioners (i.e., site evaluators, 

designers, installers, inspectors and maintenance providers). 

Action 3: Provide assistance with implementation of a model regulatory 

code using performance-based standards developed using sound 

science.

Action 4: Identify efforts needed to improve acceptance of appropriately 

managed systems.

 Strategic Goal #3: Improved accountability, control and oversight through 

enhanced state and local program implementation and 

regulatory reform.

Action 1: Continue to manage projects demonstrating approaches for 

improved state and local management programs. Share the 

results with interested parties.

Action 2: Conduct study to characterize the impact of malfunctioning 

decentralized systems, discharging and non-discharging, on 

surface and groundwater quality. Encourage states and local 

communities to inventory and assess systems. Develop easy to 

use software for inventorying and tracking systems.

Action 3: Provide assistance to states in adopting the Management 

Guidelines and meeting commitments under the Government 

Performance Results Act measure.

Action 4: Reaffirm policies that integrate EPA programs that share regulatory authority over various decentralized activities to assure compliance with regulatory requirements. These programs include 

permits for wastewater and stormwater discharges, underground 

injection control, source water assessment and protection, nonpoint source control, watersheds management, total maximum 

daily loads, enforcement and compliance, and coastal zones .

Action 5: Initiate efforts to improve management practices for key problem 

areas, including cesspools, communities lacking basic sanitation 

and significantly impacted source waters. 
8 Decentralized Wastewater Treatment Systems: A Program Strategy

 Strategic Goal #4: Improved local decision-making through improved public 

awareness.

Action 1: Continue to develop outreach and education materials, disseminate materials, and reach out to organizations representing 

state and local officials, practitioners, financing authorities, and 

environmental advocacy groups.

Action 2: Explore options to promote development of appropriate management programs when funding decentralized systems using SRF. 

Major Accomplishments/Actions to Date

 EPA’s 1997 Response to Congress on Use of Decentralized Wastewater Treatment 

Systems is considered a landmark document that, for the first time, articulated 

EPA’s position on decentralized systems. The report is at least partly responsible for 

increased activity and progress in the decentralized field.

 Since 1998, Congressional interest has increased, resulting in $46 million in funding 

specifically directed towards addressing the barriers outlined in the 1997 report to 

Congress.

 In 1999, the first annual meeting of state onsite regulators was held. The sixth 

annual meeting is planned for March, 2005.

 In May 2001, EPA issued a determination that Class V well regulations under the 

Underground Injection Control program are adequate to protect drinking water from 

existing large capacity septic system(s). As an additional layer of protection, EPA 

efforts to develop guidance for improving management practices were cited. 

 In February 2002, EPA published its Onsite Wastewater Treatment Systems 

Manual, an extremely popular document used for designing onsite systems using a 

performance-based approach.

 In February 2003, EPA’s highly successful “Wastewater Month” featured the 

distribution of thousands of brochures to inform homeowners of their responsibility to 

properly maintain septic systems.

 In March 2003, EPA released Voluntary National Guidelines for Management of 

Onsite and Clustered (Decentralized) Wastewater Treatment Systems.

 EPA’s Strategic Plan, completed in September 2003, recognizes decentralized 

systems as an important part of the nation’s wastewater infrastructure. The Strategic 

Plan incorporates a Government Performance Results Act measure to assist states in 

their adoption of EPA’s Management Guidelines. 

 In September 2003, the first national meeting of the EPA Regional Coordinators

for the Decentralized Wastewater Program was held. Another is planned for March, 

2005, and annually thereafter.
 In June 2004, EPA’s Septic System Website became one of the first designed under 

the Agency’s topics-based requirement (“web-lite”).

 As of September 2004, five states have adopted the Management Guidelines: 

Arizona, Florida, New Jersey, North Carolina and Rhode Island.

Next Steps

 EPA will share this program strategy with its partners and work toward the 

vision of appropriately performing and managed decentralized wastewater 

systems. 

 The strategy will be evaluated and updated, as appropriate, every five years. 

 EPA headquarters will work cooperatively with the EPA regional offices to 

implement the actions under each of the identified strategic goals.

Decentralized Wastewater Treatment Systems: A Program Strategy 9
10 Decentralized Wastewater Treatment Systems: A Program Strategy
Additional copies of this document, (EPA 832-R-05-002),

can be obtained from:

U.S. EPA Publications Clearinghouse

P.O. Box 42419

Cincinnati, OH 45242

Telephone: 800-490-9198

Fax: 513-489-8695

EPA 832-R-05-002

January 2005