California Department of Health Services Drinking Water Program

Emergency repairs to this transmission main make it possible to continue providing

water. However, replacement is needed soon to avoid failure and the possibility of a

water outage.
This report discusses the findings

of the first national survey of

drinking water infrastructure

needs. The survey, sponsored by EPA,

was conducted over a two-year period,

with data collection beginning in

November 1994. As part of this effort,

4,000 community water systems joined

the States, American Indian and Alaska

Native representatives, IHS, and EPA in

identifying their total infrastructure

needs. Needs were documented by

water systems’ capital improvement

plans and engineering reports.

What the Survey Covers

The survey was designed to identify

the capital infrastructure needs faced

by the nation’s publicly and privatelyowned community water systems.

Results of the survey were used to

show SDWA compliance needs, as well

as general needs for infrastructure

improvements which are not associated with the SDWA.

The survey identifies both current

needs and future needs for the 20-year

period from January 1995 through

December 2014. Current needs address

infrastructure improvements needed

now to protect public health. Future

needs are planned projects that are

necessary to continue providing safe

drinking water over the next 20 years.

The needs included in this report are

conservative because many systems

were not able to identify all of their

needs for the full 20-year period. In

some cases, systems were unable to

document all of their identified needs.

Also, the survey examined only the

needs of community water

systems; non-community water

systems were not surveyed.

Needs associated with future

growth were not included in the

survey.

In this report, drinking water capital

infrastructure needs are grouped into

four general categories. These

categories are source, treatment,

storage, and transmission and

distribution.

Source. A dependable, high-quality

source is essential to providing safe

water. To maintain adequate supply,

systems must develop new sources or

Overview

Public water systems are categorized as community water systems

or non-community water systems. This report includes needs for

community water systems only.

Community Water Systems have at least 15 service connections

used year-round by residents or regularly serve at least 25 residents

year-round. Examples of this type of water system include cities,

towns, and communities such as retirement homes.

Non-community Water Systems do not meet the definition of

community water systems, but serve an average of at least 25

individuals 60 days of the year. Examples include schools and

churches with their own water systems.

This report is intended to meet the

requirements of SDWA Sections

1452(h) and 1452(i)(4).

Types of Water Systems
Overview Drinking Water Infrastructure Needs Survey

return older sources to their full

potential. Surface water is often

collected behind dams, in impoundments, or in reservoirs. These structures protect public health and improve

water quality by allowing solids to

settle out of the water. Where supply is

reliable, water systems

sometimes use river

intakes.

Water systems also use

ground water sources

where water is taken

from underground

aquifers through drilled

wells.

Some communities must

store source water

because their sources are

unreliable. Flow may be

variable in quantity and

quality and, in some cases, the threat

of chemical spills upstream makes

source water storage essential.

Treatment. Source water quality

determines the level of treatment

required. As a general rule, surface

water sources need more treatment

than ground water sources because

surface water is more exposed to

contaminants, such as those from

agricultural run-off and wastewater

treatment plant effluent.

Most treatment needs are for microbiological contaminants, which can lead to

gastrointestinal illness and, in extreme

cases, death. Treatment for microbiological contaminants usually consists

of disinfection or both disinfection and

filtration. Treatment is also needed for

contaminants that cause chronic health

effects. These contaminants include

inorganic chemicals such as lead and

organic chemicals such as tetrachloroethylene, a component of dry

cleaning fluid. Over a lifetime,

exposure to low levels of these

contaminants poses a health risk. In

addition, some water systems must

treat for secondary (aesthetic) contaminants that cause water to look, taste, or

smell bad.

Storage. Adequate storage is important because it ensures the positive

water pressure necessary to prevent

contaminants from entering the

system. Periodic rehabilitation of

storage facilities is necessary to

Safe Drinking Water Act Needs

A portion of each category of need is

associated with the SDWA. The SDWA

sets minimum standards for all drinking

water provided by public water systems.

States must establish drinking water

standards that are at least as stringent as

those required by the SDWA. Many

States establish standards that are more

stringent.

Wisconsin Department of Natural Resources

Redwood storage tanks can last for many years.

However, like all tanks, redwood tanks can allow

entry and growth of microbiological contaminants

when they exceed their useful service life.

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Drinking Water Infrastructure Needs Survey Overview

prevent entry and growth of microbiological contaminants and to maintain

structural integrity. Storage is also

necessary because it allows systems to

provide water during periods of peak

usage.

Transmission and distribution.

Transmission pipes bring water from

the source to treatment or from

treatment to the distribution system.

Distribution pipes deliver water to the

customer. Sound transmission and

distribution systems are critical to

guarding against public health risks.

When distribution pipe begins to

deteriorate, disinfectants are less

effective in controlling microbiological

growth. If pressure is lost or if negative

pressure is induced, contaminated

water or sewage can be pulled back

into the system through leaks.

Transmission mains must be in good

condition because the failure of a

transmission main could leave a

community without water until the

main is repaired or replaced. Such an

outage is not just an inconvenience,

but also a public health threat because

sewage cannot be flushed away and

safe water is unavailable.

How the Survey Was

Conducted

In 1994, a workgroup was convened to

develop an approach for estimating the

drinking water infrastructure need for

community water systems nationwide.

The workgroup included staff from

State drinking water agencies,

American Indian and Alaska Native

representatives, IHS staff, and EPA

staff. The workgroup developed the

survey methodology and designed this

report.

Dave Schultz

The stainless steel bands on

some of these deteriorated

pipes show where previous

leaks were repaired. The

pipes' condition demonstrates that replacement has

been postponed too long.

When they are not replaced,

pipes such as these present a

health threat.

The workgroup’s methodology called

for different approaches for community

water systems in the States and for

American Indian and Alaska Native

systems. Systems in the States were

divided into three size classifications:

those serving more than 50,000 people

(large systems); those serving from

3,301 to 50,000 people (medium

systems); and those serving 3,300 and

fewer people (small systems).

All 794 large

community water

systems received

mailed questionnaires. Needs for

medium and

small community

water systems

were estimated

using statistical

surveys. Needs

of the sampled

systems were

extrapolated to

estimate total

need for medium

EPA thanks the following organizations for

contributing to the survey's success:

Alaska Native Health Board

American Water Works Association

Association of Metropolitan Water Agencies

Association of State Drinking Water Administrators

International City Managers Association

National Association of Counties

National Association of Towns and Townships

National Association of Water Companies

National Rural Water Association

National Utility Contractors Association

Native American Water Association

Navajo Nation Environmental Protection Agency

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Overview Drinking Water Infrastructure Needs Survey

To ensure the validity and accuracy of

survey responses, the workgroup

required documentation and set strict

guidelines defining criteria for

acceptable documentation. State and

EPA Regional staff evaluated needs

identified by the systems to ensure that

the documentation met survey

requirements. Following this review,

questionnaires were forwarded to EPA

Headquarters for final review before

the needs were entered into a national

database.

Project costs were derived from data

collected in the survey. Many large and

medium drinking water systems

provided documented cost estimates

for infrastructure needs in their capital

improvement plans or engineering

reports. EPA used these cost estimates,

supplemented by cost data from

States, consulting engineers, and

equipment vendors, to develop cost

models for all surveyed systems. These

models were used to estimate project

costs for respondents who documented infrastructure needs to protect

public health, but did not have accurate

cost estimates.

Water systems do not have cost

estimates for recently promulgated and

proposed regulations or for other

regulations that EPA may promulgate

in the future. Therefore, costs for these

regulations were taken from preambles

to the proposed regulations and from

draft economic analyses.

A detailed discussion of survey

methodology and a list of the types of

documentation that were used to

justify needs and costs is located in

Appendix A.

and small systems. Of the 6,800

medium-sized community water

systems, a sample of 2,760 systems

was surveyed by mailed questionnaire.

To identify the needs of the 46,500

small drinking water systems nationwide, EPA staff and contractors made

on-site determinations of need for a

sample of 537 small systems. In most

cases, State representatives accompanied EPA staff and contractors on these

visits. Exhibit 1 shows the locations of

the small systems included in the

survey.

For American Indian and Alaska Native

water systems, existing IHS databases

provided baseline information on

needs. The workgroup developed an

approach to adjust the IHS data to

include all needs allowed in the Needs

Survey. Under this approach all

15 medium American Indian systems

reported their needs on a mailed

questionnaire. Of the 869 small

American Indian and Alaska Native

systems, needs were assessed for

77 representative systems. Findings

from these assessments were used to

adjust the IHS data to derive total

needs for American Indian and Alaska

Native systems.

Documentation

• The most common form of documentation was a

system’s capital improvement plan.

• Systems also frequently submitted detailed engineering reports that described capital improvements

necessary to provide safe water.

• Where capital improvement plans and engineering

reports were unavailable, detailed explanations of

systems' needs were accepted.

• For small systems, documentation was compiled

on-site by State, EPA, IHS, and contractor staff.

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Drinking Water Infrastructure Needs Survey Overview

Not to scale

Exhibit 1: Small Drinking Water Systems in the Needs Survey Sample

American Samoa

Puerto Rico

Virgin Islands

- Counties or groups of counties included in the small system sample. Six

systems were visited in each. Water systems were visited in every State.

- Location of American Indian systems in the sample.

- Location of Alaska Native systems in the sample.

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