Using DWSRF Funds for Transmission 

and Distribution Infrastructure Needs 

WHAT S THE CHALLENGE FACING AMERICA’S TRANSMISSION AND 

DISTRIBUTION SYSTEMS? 

Using DWSRF Funds for Transmission


and Distribution Infrastructure Needs


The Drinking Water State Revolving Fund (DWSRF) program was established by the 1996 Safe Drinking Water Act (SDWA) 

Amendments and authorizes grants to states to capitalize revolving loan funds. The states provide low-interest loans to eligible 

systems for infrastructure improvements needed to ensure compliance with the SDWA and protect public health. The 

DWSRF program can play a significant role in helping systems, especially small systems, meet the challenges of complying 

with drinking water standards. 

According to the Environmental Protection Agency’s (EPA’s) 1999 Drinking Water Infrastructure Needs Survey, the total 20-

year need for transmission and distribution projects is $83.2 billion. Transmission and distribution system needs account for 

more than half of the infrastructure investments needed nationwide. This reflects the reality that the bulk of a water system’s 

assets are the pipes that move raw water from the source to the treatment plant and distribute treated water to the consumer. 

Transmission and distribution pipes that should be replaced, rehabilitated, or enlarged are a serious threat to public health. 

Rehabilitating and replacing transmission and distribution infrastructure can be costly. The DWSRF can provide assistance to 

systems to help ease this burden, increase compliance, and protect public health. 

WHAT IS THE CHALLENGE FACING AMERICA’S TRANSMISSION AND 

DISTRIBUTION SYSTEMS? 

The nation’s transmission and distribution systems are aging and deteriorating. Pipes 89% of water systems serving have life cycles that can range from 15 to over 100 years. The majority of the nation’s 

more than 10,000 people believe estimated 2 million miles of transmission and distribution pipes were laid after the they should rehabilitate or 1960s. As the pipes age, replacement needs will increase (see Figure 1). replace their pipes more often 

“Out of sight, out of mind” can explain why many water systems have neglected their 

transmission and distribution systems. Unlike treatment plants and storage tanks (which are a central focus for systems trying 

to meet applicable maximum contaminant levels (MCLs)), sub-surface pipe networks tend to receive little attention until they 

fail. When a main breaks and disrupts service, the distribution system typically receives emergency localized maintenance 

around the failure. These “patches” do little to address a system’s long-term transmission and distribution problems. 

Most water systems have a general idea of the condition of their delivery network, but detailed evaluation is time-consuming


and technologically challenging, especially for older systems. Pipes do not deteriorate at a constant rate. During the initial


period following installation, the deterioration rate is relatively slow. As pipes near the end of their life cycle, they begin to


deteriorate more rapidly, dramatically increasing the repair and upkeep expenses. In addition, the rate of deterioration of a


distribution system is not solely a function of age, but


rather a combination of factors including the characteris­


tics of the water, soil conditions, and climate. Some


Eastern cities in the United States have well functioning,


unlined cast iron pipes that are over 200 years old.


Other communities’ cast iron pipes may last less than 20


years.


The purpose of transmission and distribution infrastruc­


ture is to convey sufficient quantities of water to con­


sumers while keeping the water free from new sources of


contamination. When a pipe ruptures or a valve does


not close properly, the pressure of the system can drop


and intrusion of contaminants can occur, putting water


consumers at serious risk. Even well-run water systems


with relatively new distribution systems can experience


water main breaks.


Figure 1: Projected Annual Percentage of Transmission Lines 

and Distribution Mains Requiring Replacement, 2000 - 2075 

Percentage of Existing Pipe 

0.0% 

0.5% 

1.0% 

1.5% 

2.0% 

2.5% 

2000 2010 2020 2030 2040 2050 2060 2070 

Year 

Source: EPA Clean Water and Drinking Water Infrastructure Gap Analysis, 2002. 
HOW DOES A TRANSMISSION TRANSMISSION AND DISTRIBUTION DISTRIBUTION SYSTEM FAIL?


A transmission and distribution system fails when the system is no longer able to transport water or potable water degrades to 

the point at which the health of consumers is threatened. There are several means by which the transmission and distribution 

system can fail (see Exhibit 1): 

Two major pipe breaks caused an 

1. External contamination from intrusion and permeation. outbreak of E. coli in Cabool, 

2. Contamination from transmission and distribution pipes. Missouri from December 1989 to 

3.	 Contamination from cross-connections and backflow. January 1990. Four people died and 

another 240 became sick from the 

distribution system failure. 

Exhibit 1: Causes of Transmission and Distribution System Failures 

F AILURE D EFINITION C AUSES/SOURCE C ONTAMINATION

E xternal Contamination

I ntrusion T he flow of nonpotable water into

m ains through leakage points,

s ubmerged air valves, faulty seals,

o r other openings. The volume of

i ntrusion can range from milliliters to

h undreds of gallons.

• Main breaks

• Sudden changes in water demand or flow

• Uncontrolled pump starting or stopping

• Opening and closing of fire hydrants

• Power failures

• F ire flow (in systems with inadequate storage o

s upply)

• Faulty joints

• Pipes below the water table

• Improper water main installation or repair

• Microbiological

• Chemical

• Excess disinfectants

• Loss of disinfectant residual

• pH & alkalinity instability

P ermeation T he passage of external

c ontaminants through porous plastic

p ipe.

• I nteraction of plastic pipes with substances in th

e xternal environment

• Stagnation of water in localized areas

• Volatile organic

c ontaminants

• Vinyl chloride

• pH & alkalinity instability

C ontamination from Infrastructure

L eaching T he dissolution of metals, solids,

a nd chemicals into drinking water.

• Aggressive water reacting with pipe linings

• Stagnation of water in localized areas

• Metals

• Asbestos

N itrification O xidation of nitrogen compounds to

n itrate or nitrite.

• Use of chloramines

• Presence of nitrifying bacteria and ammonia

• Stagnation of water in localized areas

• Nitrite and nitrate

• pH & alkalinity instability

• Loss of disinfectant residual

• Biofilm growth

C orrosion E xternal or internal deterioration of

t he chemical integrity of the piping

m aterial.

• Microorganisms

• Reactions of pipe lining with water

• Stagnation of water in localized areas

• Chemical

• Biofilm growth

C ontaminations from Cross-Connections and Backflow

C rossC onnections

P oints in the distribution system

w here nonpotable water can come

i nto contact with potable water,

p roviding a pathway for backflow of

n onpotable water into potable

s upplies.

• C onnection of heating/cooling, waste disposal, o

i ndustrial manufacturing systems to potable water

s upplies when the pressure in the external system

e xceeds the pressure in the distribution system

• Intentional contamination

• Microbiological

• Chemical

• Excess disinfectants

• Loss of disinfectant residual

• pH & alkalinity instability

• Biofilm growth

B ackflow E ither reduced pressure in the

d istribution system (backsiphonage)

o r the presence of increased

p ressure from a nonpotable source

( backpressure) that reverses the flow

s o nonpotable water flows into the

p otable water system.

• M ain breaks, pump failure, firefighting, or opening fir

h ydrants for recreation in a system with inadequate

s torage or supply

• I mproperly operating valves, loose-fitting servic

m eter connections, surge or feed tank draining, a

s udden change in demand, hilly terrain, limited

p umping capacity, high customer demand, and power

l oss

• Pressure transient (also called surge or water hammer)

• Intentional contamination

r

e

r

e

e
WHAT PUBLIC HEALTH THREATS ARE CREATED BY SYSTEM FAILURES?

WHAT INFRASTRUCTURE INVESTMENTS ARE NEEDED?

WHAT PUBLIC HEALTH THREATS ARE CREATED BY SYSTEM FAILURES?


Contamination introduced into the transmission and distribution 

network can cause many problems for a water system. EPA has 

published several National Primary Drinking Water Regulations 

(NPDWRs) that address public health issues related to potential 

chemical and microbial contamination in the distribution system, 

including the Total Coliform Rule, the Lead and Copper Rule, the 

Surface Water Treatment Rule, and the Stage 1 Disinfectants and 

Disinfection Byproducts Rule. 

The most acute threat from transmission and distribution system 

failure is that old pipe, weak and brittle from hard-to-detect internal or 

external corrosion, will break, causing the pressure in the distribution 

system to plummet. Any break or leak in a distribution system can 

The Borough of Williamsburg has served its residents and parts 

of neighboring Woodbury and Catherine Townships with its 

water system for more than 90 years. In the 1980s, two reservoirs 

used by the system had to be abandoned due to Giardia 

contamination and the poor condition of the system's 

transmission lines. ven after the reservoirs were abandoned, 

the existing lines remained undersized and in poor condition, 

resulting in pressure, flow, and leak problems in some areas. n 

May 1997, Williamsburg received a $4.2 million DWSRF loan. 

The project included the installation of a booster pumping station, 

new storage tank, eight miles of mains, and the replacement of 

every meter in the system. The project was completed in 1998. 

Williamsburg, Pennsylvania ennsylvania

E

I

potentially draw chemical and microbial contaminants into the distribution system. Sewer pipes are often installed adjacent to 

drinking water mains. Even short periods of exposure to acute contaminants, like bacteria and viruses, can threaten public 

health. From 1981 to 1998, the Centers for Disease Control documented 57 waterborne disease outbreaks related to crossconnections, resulting in 9,734 illnesses. The American Water Works Association estimates that 78% of all waterborne disease 

outbreaks in recent history were caused by cross-connections and backflow. 

WHAT INFRASTRUCTURE INVESTMENTS ARE NEEDED? 

Many homes in the six subdivisions served by 

the Clinton Public Works Authority were served 

by cast iron, dead end lines with leaded joints. 

Clinton's problems included inadequate water 

availability, stale water caused by dead-ends, and 

lead contamination. WSRF loan 

financed the majority of the project, which 

included: replacing existing substandard lines 

with new PVC water lines; constructing a loop 

trunk line to supply the area; and replacing fire 

hydrants, valves, and appurtenances. 

Clinton, Oklahoma Oklahoma 

A $644,000 D

The 1999 Drinking Water Infrastructure Needs Survey determined that water 

systems need to invest $83.2 billion by 2018 to improve the nation’s drinking water 

transmission and distribution infrastructure (see Figure 2). Transmission and 

distribution infrastructure accounts for more than 55% of the total water infrastructure investment needed nationwide. At least $65.6 billion is needed immediately to 

rehabilitate or replace pipes to adequately protect public health. As water systems 

modernize their treatment capability, they are becoming increasingly aware of the 

need to upgrade their distribution systems so that they can reliably deliver safe water. 

This attention should continue to increase—EPA estimates the transmission and 

distribution infrastructure need will be even greater after 2019 as more pipes and 

valves reach the end of their useful life. 

Rehabilitating and replacing transmission and distribution infrastructure can be costly because of the difficulty in accessing pipes


and valves that are below ground (and often under streets). The majority of water main replacement is still performed using


open-cut or open-trench methods. These methods maximize the public burden both in terms of cost and public nuisance.


Recent technological advances in trenchless technologies, which have become commonplace in Europe, are being considered by


more water systems across the country because they minimize the


need for excavation and can save 20 percent to 60 percent in


overall costs.


Besides infrastructure investment, there are many other actions


water systems can take to improve their transmission and distribu­


tion systems. Many threats can be minimized by modeling the


transmission and distribution network to identify problem areas,


inspecting the infrastructure for leakage and corrosion and the


plumbing of customers for cross-connections, and properly


selecting the materials used in the transmission and distribution


system infrastructure. In addition, water systems can utilize tools


such as facility improvement plans and asset management. By


developing a comprehensive strategic plan, a water system can


potentially improve the process for building, maintaining, and


improving its transmission and distribution infrastructure.


Figure 2: Total Transmission & Distribution Infrastructure 

Need by System Size (in billions of 1999 $) 

$0 

$5 

$10 

$15 

$20 

$25 

$30 

$35 

Billions of Dollars 

$40 

$45 

CWSs* 

Serving 

< 3,300 

CWSs* 

Serving 

3,301 - 50,000 

CWSs* 

Serving 

> 50,000 

Non-Profit 

NCWSs** 

American Indian 

& Alaska Natives 

Source: EPA 1999 Drinking Water Infrastructure Needs Survey, 2001. 

*CWSs = Community Water Systems 

**NCWSs = Non-Community Water Systems 
HOW CAN THE DWSRF ASSIST SYSTEMS? SYSTEMS? 

States use DWSRF capitalization grant monies to provide lowinterest loans to publicly- and privately-owned public water systems 

for infrastructure improvements needed to continue to ensure safe 

drinking water. States may offer principal forgiveness, reduced 

interest rates, or extended loan terms to systems identified by the 

state as serving disadvantaged communities. States also have the 

ability to reserve a portion of their grants (i.e., set-asides) to finance 

activities that encourage enhanced water system management and 

help prevent contamination problems through source water protection measures. Based on the Fiscal Year 2002 appropriation of $850 

million, capitalization grants ranged from $8.0 million to $82.4 

million per state. 

Most capital projects needed to upgrade a transmission and distribution system—including replacing fragile water mains and worn-out 

valves—are eligible for funding under the DWSRF (see Exhibit 2). 

Consolidation and restructuring of systems can be a cost-effective 

option for small systems that need massive infrastructure investment. 

The DWSRF can fund consolidation, including situations where a 

system is unable to maintain compliance for technical, financial, or 

managerial reasons. 

States can use set-aside funds from the DWSRF to assist systems 

directly as well as to enhance their own program management 

activities (see Exhibit 2). A state may use set-asides to make administrative improvements to the entire drinking water program, which 

faces increased costs in ensuring the integrity of transmission and 

distribution systems across the state. States can also train small 

systems on how to better manage and maintain their water delivery 

network, as well as provide technical assistance to help systems 

E xhibit 2: Transmission and Distribution

P rojects/Activities Eligible for DWSRF Funding

Type of Project/Activity

Eligible Under

Infrastructure

Fund

Eligible Under

Set-Asides

T reatment

P igging Y es N 

L ining Y es* N 

C orrosion Control Y e N 

B ackflow Prevention Devices Y e N 

B ackup Power Y e N 

B ackup Pumps Y e N 

D isinfectant Booster Stations Y e N 

F lushing Hydrants Y e N 

S urge Control Devices Y e N 

P ump Replacement Y e N 

V alve Replacement Y e N 

W ater Main Replacement Y e N 

W ater Main Expansion Y e N 

L ooping Dead-end Mains Y e N 

W ater Meters Y es** N 

S ystem Consolidation Y es N 

S ystem Restructuring Y es Y e

S ystem Administrative Improvements

H ire Staff N N 

S taff Training N Y e

P ublic Outreach N Y e

M onitoring N N 

R ate Increase Process N Y e

S tate Administrative Improvements

H ire Staff N Y e

S taff Training N Y e

P ublic Outreach N Y e

C ompliance Oversight N Y e

E nforcement N Y e

P ilot Studies N Y e

S anitary Surveys N Y e

D istribution System Assessments N Y e

* o

* o

s o

s o

s o

s o

s o

s o

s o

s o

s o

s o

s o

s o

* o

o

s

o o

o s

o s

o o

o s

o s

o s

o s

o s

o s

o s

o s

o s

*Capital expenditures only. 

** Structural lining only. 

***Must be owned and maintained by system. 

identify the 

most costVermont used $150,000 in Fiscal Year 1999 DWSRF set-aside 

funds to contract with engineering firms to develop facility 

improvement plans for 79 small water systems that serve less 

than 500 people. 

Kountry Trailer Park, serving 44 mobile homes in the town of 

Bristol, identify ways to overcome the occasional bacteriological 

and pressure related problems from which they had been 

suffering. The consultant suggested installing several flushing 

hydrants, replacing sections of main, and working with the 

town to maintain an adequate disinfection residual at the park 

entrance. The consultant also documented the costs and helped 

identify potential sources of funding. 

Vermont 

On behalf of the state, a consultant helped 

effective upgrade


strategy (i.e., replacement versus rehabilitation). In addition, states


can provide assistance to small systems to cover the costs of project


planning and design for infrastructure improvements.


Since the DWSRF program is managed by states, project and set-


aside funding varies according to the priorities, policies, and laws


within each state. Given that each state administers its own program


differently, the first step in seeking assistance is to contact the state


DWSRF representative, who can be found on the EPA DWSRF


website.


FOR MORE INFORMATION... 

DWSRF Website: General Information

http://www.epa.gov/safewater/dwsrf.html 

Transmission & Distribution Fact Sheets: 

http://www.epa.gov/safewater/tcr/tcr.html 

SDWA Hotline 

1-800-426-4791 

EPA's Ground Water & Drinking 

Water Website: 

http://www.epa.gov/safewater/ 

Office of Ground Water and 

Drinking Water (4606M) 

EPA 816-F-03-003 

February 2003 

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