Information Collection Request for the 2015 Drinking Water 

Infrastructure Needs Survey and Assessment (DWINSA)

(Supporting Statement for ICRAS and ROCIS)

Final Draft October 23, 2014

Prepared by:

The Cadmus Group, Inc.

100 5th Avenue, Suite 100

Waltham, MA 02451

Prepared for:

U.S. Environmental Protection Agency

Office of Ground Water and Drinking Water

Drinking Water Protection Division
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ICR for 2015 DWINSA i September 4, 2014

Table of Contents

PART A OF THE SUPPORTING STATEMENT .......................................................................................1

A.1 IDENTIFICATION OF THE INFORMATION COLLECTION....................................................1

A.1.a Title of the Information Collection Request.....................................................................1

A.1.b Short Characterization......................................................................................................1

A.2 NEED FOR AND USE OF THE COLLECTION...........................................................................2

A.2.a Authority and Need for the Collection.............................................................................2

A.2.b Use and Users of the Information ....................................................................................2

A.3 NONDUPLICATION, CONSULTATIONS AND OTHER COLLECTION CRITERIA..............3

A.3.a Nonduplication.................................................................................................................3

A.3.b Public Notice Required Prior to ICR Submission to OMB..............................................4

A.3.c Consultations....................................................................................................................4

A.3.d Effects of Less Frequent Collection .................................................................................5

A.3.e General Guidelines...........................................................................................................5

A.3.f Confidentiality Questions.................................................................................................5

A.3.g Sensitive Questions..........................................................................................................6

A.4 THE RESPONDENTS AND THE INFORMATION REQUESTED.............................................8

A.4.a Respondents/NAICS Codes .............................................................................................8

A.4.b Information Requested .....................................................................................................9

A.5 INFORMATION COLLECTED: AGENCY ACTIVITIES, COLLECTION METHODOLOGY 

AND INFORMATION MANAGEMENT....................................................................................14

A.5.a Agency Activities...........................................................................................................14

A.5.b Collection Methodology and Management ....................................................................15

A.5.c Small Entity Flexibility ..................................................................................................19

A.5.d Collection Schedule........................................................................................................19

A.6 ESTIMATING THE BURDEN AND COST OF THE COLLECTION .......................................20

A.6.a Respondent Burden ........................................................................................................20

A.6.b Respondent Costs...........................................................................................................32

A.6.c Agency Burden and Cost................................................................................................33

A.6.d Estimating Respondent Universe and Total Burden and Costs......................................36

A.6.e Bottom Line Burden Hours and Costs ...........................................................................36

A.6.f Reasons for Change in Burden.......................................................................................40

A.6.g Burden Statement ...........................................................................................................40

PART B OF THE SUPPORTING STATEMENT (FOR STATISTICAL SURVEYS).............................41

B.1 SURVEY OBJECTIVES, KEY VARIABLES AND OTHER PRELIMINARIES ......................43

B.1.a Survey Objectives ..........................................................................................................43

B.1.b Key Variables.................................................................................................................43

B.1.c Statistical Approach .......................................................................................................44

B.1.d Feasibility.......................................................................................................................45

B.2 SURVEY DESIGN........................................................................................................................46

B.2.a Target Population and Coverage ....................................................................................46

B.2.b Sample Design ...............................................................................................................47

B.2.c Precision Requirements..................................................................................................53

B.2.d Data Collection Instrument Design ................................................................................55
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B.3 PRE-TESTS AND PILOT TEST...................................................................................................55

B.3.a Pre-tests..........................................................................................................................55

B.3.b Pilot Test ........................................................................................................................56

B.4 COLLECTION METHODS AND FOLLOW-UP ........................................................................56

B.4.a Collection Method..........................................................................................................56

B.4.b Survey Response and Follow-up....................................................................................56

B.5 ANALYZING AND REPORTING SURVEY RESULTS............................................................57

B.5.a Data Preparation.............................................................................................................57

B.5.b Analysis..........................................................................................................................57

B.5.c Reporting Results...........................................................................................................57
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List of Appendices

Appendix A – Public Notice Required Prior to ICR Submission to OMB

Appendix B – Data Collection Instrument and Lists of Codes

Appendix C – Comments and Response to Comments Received on the 2015 DWINSA Peer Review

Appendix D – Comments and Response to Comments Received on the First Federal Register Notice
ICR for 2015 DWINSA iv September 4, 2014

List of Tables

Exhibit A-5-1 Collection Schedule.............................................................................................................19

Exhibit A-6-1 Estimated Average Unit Burden for Systems Serving More Than 50,000 Persons ............23

Exhibit A-6-2 Estimated Average Unit Burden for Systems Serving 3,301 to 50,000 Persons.................26

Exhibit A-6-3 State Unit Burden for Up-Front Activities ..........................................................................27

Exhibit A-6-4 State Unit Burden for Systems Serving More Than 50,000 Persons...................................29

Exhibit A-6-5 Estimated State Average Unit Burden for Systems Serving 3,301 to 50,000 Persons........31

Exhibit A-6-6 Total Burden and Cost to Water Systems............................................................................32

Exhibit A-6-7 Total Burden and Cost to States ..........................................................................................33

Exhibit A-6-8 Burden/Cost to EPA (Excluding Contractor Activities)......................................................34

Exhibit A-6-9 Burden/Cost of Contractor Activities..................................................................................35

Exhibit A-6-10 Bottom Line Respondent Burden ......................................................................................36

Exhibit A-6-11 Burden Hours and Costs for Respondents per Year ..........................................................36

Exhibit A-6-12 Bottom Line Burden Hours and Costs for EPA (including EPA’s contractor) .................37

Exhibit A-6-13 Disaggregated Burden by Affected Information Collection (IC) Entities.........................38

Exhibit B-2-1 State Sample Sizes...............................................................................................................49
ICR for 2015 DWINSA 1 September 4, 2014

PART A OF THE SUPPORTING STATEMENT

A.1 IDENTIFICATION OF THE INFORMATION COLLECTION

A.1.a Title of the Information Collection Request

The title of this information collection request (ICR) is Information Collection Request for the 2015

Drinking Water Infrastructure Needs Survey and Assessment (DWINSA). The Office of Management and 

Budget (OMB) control number for this ICR is 2234.04; EPA ICR No. 2014-0274.

A.1.b Short Characterization 

The Environmental Protection Agency (EPA) will conduct an assessment to estimate the capital 

investment needs of drinking water systems eligible to receive Drinking Water State Revolving Fund 

(DWSRF) monies. The nationwide assessment will be conducted by the Drinking Water Protection 

Division (DWPD) of EPA’s Office of Ground Water and Drinking Water (OGWDW). The data collection 

is authorized by Sections 1452(h) and 1452(i)(4) of the Safe Drinking Water Act (SDWA) and will be 

used to estimate the capital investment cost of providing safe drinking water to consumers over a 20-year 

period. The data from the report will also be used to allot DWSRF monies among states.

In determining an appropriate survey approach, EPA strives to achieve an acceptable level of statistical 

precision and avoid measurement errors while minimizing the burden placed on the states, water systems

and the Agency in conducting the survey effort. The two sources of potential inaccuracy in the survey 

results are “measurement error,” which arises when determining the need for each individual 

infrastructure investment, and “sampling error,” which occurs when estimating the needs of all water 

systems from a representative sample of those systems. EPA strives to reduce measurement error by 

relying on information from and judgment of those individuals most familiar with and directly 

responsible for the infrastructure, the owners and operators of water systems, and by assuring that their 

estimates of investment needs are within the context of the industry’s best engineering practices. EPA 

addresses the sampling error by identifying and specifying statistical precision targets for the survey and 

determining the necessary sample and sub-sample sizes to achieve those targets

The 2015 DWINSA will focus on data collection from water systems overseen by state drinking water 

programs, referred to in previous DWINSA ICRs and reports to Congress as a “state survey.” All states 

have committed to help EPA administer the 2015 DWINSA with at least a minimum set of activities. For 

this document, the term “states” refers to all 50 states, the U.S. territories (Guam, U.S. Virgin Islands, 

Northern Mariana Islands and American Samoa), Puerto Rico and the District of Columbia. 

EPA will conduct a census of all community water systems (CWSs) serving populations more than 

100,000. For CWSs serving populations of 3,301 to 100,000, EPA proposes to use a modified panel 

approach that will reassess the needs of most of the water systems that participated in the 2011 DWINSA. 

The modified panel approach will involve dropping a random selection of 25 percent of the systems 

serving 3,301 to 100,000 people that participated in the 2011 DWINSA and then drawing a random 

sample to replace those systems in the survey for the 2015 DWINSA. The approach will be implemented 

by state and stratum. 

Fifteen states are expected not to participate in the statistical portion of the survey (i.e., collecting data 

from systems serving 3,301 to 100,000 persons). The needs of the participating states will be used to 

estimate the needs for systems serving 3,301 to 100,000 persons for the states that are not included in the 

statistical portion of the survey. All states with systems serving more than 100,000 persons will 

participate in the census portion of the survey. 
ICR for 2015 DWINSA 2 September 4, 2014

For the 2015 DWINSA, EPA will not collect data from small CWSs in states (those serving 3,300 and

fewer people), not-for-profit noncommunity water systems (NPNCWSs) 1 or American Indian or Alaska 

Native Village water systems. EPA will estimate the infrastructure needs for CWSs serving 3,300 and 

fewer persons based on the average system need calculated in the 2007 DWINSA, adjusted for inflation.

Similarly, the infrastructure needs for NPNCWSs will be based on the 1999 DWINSA results, adjusted 

for inflation. The 2011 DWINSA included a survey of American Indian and Alaska Native Village water 

systems; those results will be adjusted for inflation for the 2015 DWINSA. 

The data collection instrument to be used consists of project tables in which the water systems list all their 

capital improvement projects for the survey period of January 1, 2015, to December 31, 2034. The data 

collection instrument used will be in a Microsoft Excel format, with no significant changes in content or 

questions from the previous three DWINSAs.

The effort for the 2015 DWINSA will involve 2,915 respondents (2,859 water systems and 56 states), 

requiring 37,194 hours at a total cost to the respondents of $1,734,004. Section A.6, Estimating the 

Burden and Cost of the Collection, provides a detailed description of the unit burden and costs for this 

collection. The average water system burden per response is 5.53 hours2and the average burden for a 

state response is 381.64 hours.3

A.2 NEED FOR AND USE OF THE COLLECTION

A.2.a Authority and Need for the Collection 

EPA (the Agency) is conducting this DWINSA pursuant to its authority under Sections 1452(h) and 

1452(i)(4) of the SDWA. Section 1452(h) requires that “the Administrator shall conduct an assessment of 

water system capital improvement needs of all eligible public water systems in the United States and 

submit a report to the Congress containing the results of such assessment within 180 days after the date of 

the enactment of the SDWA Amendments of 1996 and every 4 years thereafter.” Section 1452(i)(4) 

requires that “the Administrator, in consultation with the Director of the Indian Health Service and Indian 

Tribes, shall, in accordance with a schedule that is consistent with the needs surveys conducted pursuant 

to subsection (h), prepare surveys and assess the needs of drinking water treatment facilities to serve 

Indian Tribes, including an evaluation of the public water systems that pose the most significant threats to 

public health.”

A.2.b Use and Users of the Information 

The results of the DWINSA will be used as a basis for allocation of DWSRF funds among states and 

contributes to the allocation of DWSRF funds to EPA Regions and Tribes with primacy enforcement 

authority for American Indian and Alaska Native Village water systems. In addition, many water systems 

have empirical data on the cost of compliance with SDWA regulations. A national assessment improves

the Agency’s ability to gauge long-term capital costs of SDWA regulations. 

EPA will collect two types of system-specific information: 

1. System inventory and characteristics data (i.e., name and address of the system, contact person, 

population served, total design capacity, number of connections, primary source, whether the 

 

1 NPNCWSs are also eligible for DWSRF funding.

2 See Exhibit A-6-6.

3 See Exhibit A-6-13.
ICR for 2015 DWINSA 3 September 4, 2014

water system is privately or publicly owned and whether the water system purchases/sells water 

from/to another water system). 

2. Information on capital improvement projects. 

The specific uses of each data type vary. EPA will use system inventory and characteristics data to 

characterize CWSs nationwide and, in some cases, to model costs for individual water systems’ capital 

improvement projects. EPA will use all data collected to estimate state and national needs.

Respondents will identify capital improvement needs on a project-by-project basis and identify the reason 

for the project on the data collection instrument. EPA will collect information on the proposed 

infrastructure to be installed, replaced, rehabilitated, upgraded or expanded. EPA will use the information 

to assess project allowability, which is determined by DWSRF funding allowability and DWINSA 

policies.

Respondents will also identify either a documented cost estimate for the project or will provide adequate 

information so that EPA can model the cost of the project. The information needed to model the cost will 

depend on the type of need. For example, EPA may collect information on the size and number of meters

or the diameter and length of transmission or distribution lines. For the 2011 DWINSA, approximately 15

percent of the projects reported had documented costs; the costs for the remaining 85 percent of projects

were modeled. 

A.3 NONDUPLICATION, CONSULTATIONS AND OTHER COLLECTION 

CRITERIA

The following sections verify that this information collection satisfies the OMB’s non-duplication and 

consultation guidelines and does not duplicate another collection.

A.3.a Non-duplication

To the best of EPA’s knowledge, up-to-date state-by-state information on water systems’ capital needs is 

not available from any other source. Some of the data collection efforts EPA considered include the 

following:

 Safe Drinking Water Information System (SDWIS). Inventory data and information on system 

characteristics have been collected by states and EPA Regions and entered into the SDWIS. For 

systems in the statistical sample, EPA will pre-populate the SDWIS system characteristics data 

(i.e., name and address of the system, contact person, address, population served, total design 

capacity, number of connections, primary source, whether the system is privately or publicly 

owned and whether the system purchases/sells water from/to another water system) on the 2015

DWINSA form and ask the respondents to provide information only if the SDWIS data are 

inaccurate or missing. SDWIS does not contain information on water systems’ capital needs. 

 Community Water System Survey (CWSS). EPA completed a statistical survey in 2006 that 

focused on the operating and financial characteristics of CWSs. The CWSS is addressed in the 

ICR for the National Survey of the Financial and Operating Characteristics of Community Water 

Suppliers. The CWSS had a different objective than the DWINSA. The CWSS was designed to 

characterize technical and financial aspects of CWSs. In contrast, the DWINSA will be used to 

develop national estimates of capital needs. In addition, the CWSS’s targeted precision was on a 

national basis, whereas the DWINSA will provide state-by-state estimates. 
ICR for 2015 DWINSA 4 September 4, 2014

 Economic Analyses (EAs) for National Primary Drinking Water Regulations. The Agency 

has developed EAs for its National Primary Drinking Water Regulations. These documents 

estimate the costs of complying with proposed and final regulations. EAs do not typically include 

an estimate for capital projects needed to maintain compliance with existing regulations.

Therefore, the EAs are not an adequate substitute for the DWINSA. In addition, the EAs provide 

nationwide estimates. As discussed above, EPA is conducting the DWINSA because the Agency 

needs a state-by-state estimate to develop the allocation formula for the DWSRF. Also, EAs may 

not, depending on when they were developed, reflect currently available contaminant occurrence

data or current or emerging treatment technology costs. 

 State Needs Surveys. Several states have conducted needs surveys of their own drinking water 

systems. The state results cannot be extrapolated to the nation as a whole because the state 

surveys do not use consistent methodologies and do not account for national variations in system 

characteristics and needs.

 1995, 1999, 2003, 2007 and 2011 DWINSAs. Under the SDWA, EPA must conduct the 

DWINSA every four years. The approach for the 2015 DWINSA will incorporate some data

collected during the previous assessments updated to reflect 2015 construction costs and shifts in 

the number and characteristics of the Nation’s water utilities. The approach for the 2015

DWINSA also includes substantial new data from the field to ensure up-to-date information on 

changes in the relative level of infrastructure needs at the state level as well as change in the total 

national need.

A.3.b Public Notice Required Prior to ICR Submission to OMB 

To comply with the 1995 Amendments to the Paperwork Reduction Act (PRA), EPA is soliciting public 

comment on this ICR for a 60-day period before it is submitted to OMB. Specifically, EPA published a 

notice in the Federal Register (FR) requesting comment on the estimated respondent burden and other 

aspects of this ICR (2234.04). This notice is included in Appendix A. Before submission to OMB, EPA 

will consider any comments received and determine if any adjustments are needed to the burden and cost 

calculations or to the supporting statement for this ICR. Comments received and EPA’s responses will be

included in Appendix D. An additional Federal Register notice will be published when this ICR is 

submitted to OMB. The public comment period for this additional notice will be 30 days.

A.3.c Consultations 

In May 2014, EPA assembled a workgroup that consisted of EPA Headquarters, EPA Regions and state 

representatives to discuss the approach for the 2015 DWINSA. The purposes of the workgroup were to 

gather information on state and/or regional concerns, to discuss lessons learned during the 2011 DWINSA 

and to discuss new policies for the 2015 DWINSA. The information gathered by the workgroup 

contributed to the development of the methodology for the 2015 DWINSA. 

For the 2007 DWINSA, the data collection instrument and some policies were modified substantially. 

Consequently, in 2007, EPA conducted a pre-test of the data collection instrument (see B.3 for more 

information on the pre-test) and a formal peer review of the 2007 DWINSA statistical methodology and 

policies. Based on comments received from the peer review and the pre-test, EPA made modifications to 

the data collection instrument, statistical procedures and survey polices. 

The data collection instrument was further modified for the 2011 DWINSA by the addition of optional 

questions to gather information on “green” and climate readiness infrastructure projects. Consequently, 

EPA conducted a limited peer review focused on these new questions. The peer review included experts 
ICR for 2015 DWINSA 5 September 4, 2014

familiar with the operations of drinking water systems and “green” and climate readiness issues. Based on 

comments received from the peer review, EPA developed an addendum to the 2011 survey instructions 

that provided additional explanation about why EPA was interested in collecting information on “green” 

and climate readiness infrastructure projects as well as providing examples of what might constitute 

“green” and climate readiness. Based on the limited number of states that submitted projects with “green” 

or climate readiness attributes indicated, EPA concluded these attributes were likely underreported in 

2011. For the 2015 DWINSA, the “green” and climate readiness questions will be removed from the data 

collection instrument. Instead, EPA will explore streamlined approaches that might enable the Agency, 

during the Survey review process, to identify and flag projects that are likely to have “green,” climate 

readiness or climate resilience attributes. 

The other significant modification for the 2015 data collection methodology will be the use of a modified 

panel approach. This approach uses a longitudinal study method for the survey with a 25 percent refresh 

of the sample (by state and by strata) of systems serving 3,301 to 100,000 population (this approach is 

described in more detail in Section B.2). EPA conducted a peer review of the applicability of this 

modified panel approach and the details of the approach. EPA considered comments from the peer review 

and made changes to the approach as necessary as described in Appendix C.

A.3.d Effects of Less Frequent Collection 

The 2015 DWINSA is a single collection and does not involve periodic reporting or recordkeeping.

A.3.e General Guidelines 

The 2015 DWINSA does not violate any guidelines for information collection activities specified by 

OMB. Specifically, the 2015 DWINSA respondents are not required to:

 Report information to EPA more often than quarterly.

 Retain records for more than three years.

 Complete the data collection instrument in fewer than 30 days.

 Maintain or provide information in a format other than that in which it is customarily maintained.

 Submit proprietary, trade secret or other confidential information.

 Submit more than one original and two copies of any document.

The information collection:

 Is a statistical assessment designed to produce data that can be generalized to the universe of the 

study (see Section B.2).

 Does not provide remuneration to participants.

 Will transcribe information collected into an automated format.

 Is designed with small entities particularly in mind (see Part A.5.c).

 Does not concern grants or grantees.

 Is voluntary.

A.3.f Confidentiality Questions 

This information collection does not require the respondent to disclose any confidential information. 

Respondents are not obliged to respond to this strictly voluntary information collection. Further, 

respondents could eliminate any confidential business information from their reply. 
ICR for 2015 DWINSA 6 September 4, 2014

A.3.g Sensitive Questions 

The 2015 DWINSA does not ask sensitive questions.
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A.4 THE RESPONDENTS AND THE INFORMATION REQUESTED

A.4.a Respondents/NAICS Codes 

NAICS Codes

The respondents for the 2015 DWINSA are CWSs in states and state agencies that include drinking water 

programs. CWSs are considered public water systems. According to 40 CFR Part 141.2, a CWS is a 

“public water system which serves at least 15 service connections used by year-round residents or 

regularly serves at least 25 year-round residents.” The North American Industry Classification System 

(NAICS) code for a public water system is 221310. State agencies that include drinking water programs 

are classified as NAICS code 924110 (Administration of Air and Water Resources and Solid Waste 

Management Programs) or 926130 (Regulation and Administration of Communications, Electric, Gas and 

Other Utilities). Ancillary systems (i.e., those that supplement the function of other establishments like 

factories, power plants, mobile home parks, etc.) cannot be categorized in a single NAICS code. For 

ancillary systems, the NAICS code is that of the primary establishment or industry.

Respondents

EPA will gather information from CWSs serving more than 3,300 persons. For the purposes of this 

document, EPA will use inventory and sample numbers from the 2011 DWINSA to approximate sample 

sizes for 2015.

Because of their variability and significant contribution to the overall drinking water capital investment 

need, water systems serving more than 100,000 persons will be sampled with certainty. The burden 

estimates assume that EPA will survey approximately 612 water systems that serve more than 100,000 

persons.

There are 8,927 water systems that serve populations of 3,301 to 100,000. Surveying all of these water 

systems would impose a large burden on respondents, EPA and states. Therefore, EPA will select a 

statistically representative sample of water systems serving populations of 3,301 to 100,000. As described 

in Section B.2., a modified panel approach will be used to select water systems to be sampled. This 

approach will result in a re-sampling of 75 percent or more of the water systems that were sampled in 

2011. Based on the sampling conducted in 2011, the burden estimates assume that EPA will survey 

approximately 2,247 water systems that serve 3,301 to 100,000 persons.

EPA will not collect new needs data from NPNCWSs, small CWSs in states, Alaska Native Village water 

systems or American Indian water systems. EPA will instead extrapolate the findings for these systems 

from previous Needs Surveys to 2015 dollars taking into account changes in the number of these systems 

in current operation.

For purposes of this burden statement, EPA is assuming that fifty-six states (50 states plus the District of 

Columbia, Puerto Rico, Northern Mariana Islands, American Samoa, Guam and the U.S. Virgin Islands) 

will be called upon to provide support and information for the approximately 2,859 systems for the 2015

DWINSA. 
ICR for 2015 DWINSA 9 September 4, 2014

A.4.b Information Requested 

As previously discussed, EPA will collect two types of information from systems: 

1. System inventory and characteristics. 

2. Information on capital improvement projects. 

EPA anticipates that respondents will provide varying levels of information by system size category. 

Based on experience from the previous five DWINSAs, EPA generally expects larger systems (e.g., those 

systems serving more than 50,000 persons) to have a well-developed understanding of their capital needs 

and the costs for meeting them. Almost all of these systems will have detailed Capital Improvement Plans 

(CIPs). Most of these systems will be capable of providing accurate information on cost. Most mediumsized systems (e.g., those systems serving 3,301 to 50,000 persons) can provide reliable data on their 

needs and some can provide cost estimates for meeting their needs. The information that respondents will 

be asked to provide is generally maintained and reported as a function of the management and operation 

of the water system. 

A.4.b.i Data Items 

2015 DWINSA – Systems Serving More Than 3,300 Persons

The data collection instrument asks respondents to verify or correct system characteristic information 

(i.e., name and address of the system, contact person, address, population served, total design capacity, 

number of connections, primary source, whether the water system is privately or publicly owned and 

whether the water system purchases/sells water from/to another water system). It is customary business 

practice for the water system to maintain this information. The respondent will either indicate that the 

information is correct as provided or enter the correct information in the space provided. States verify this 

information in advance of the data collection instrument being sent to the water systems. Based on 

previous assessments, EPA anticipates that very few water systems will need to correct the information 

provided. 

In addition, the respondent is asked to provide information associated with specific types of projects:

 source;

 treatment;

 finished or treated water storage and pumping;

 transmission and distribution; and

 backflow prevention devices/assemblies, service lines, valves, water meters and other (projects 

not associated with one of the specified project types).

For each project, the respondent is asked to:

 Briefly describe the needed capital project (e.g., “routine distribution system replacement,”

“filtration plant upgrade,” “high service pump replacement,” “corrosion control treatment,” 

“storage tank rehabilitation”). Information is collected on a project-by-project basis because it is 

most commonly available to respondents in that form and because documentation, when 

available, is usually developed on a project-by-project basis.
ICR for 2015 DWINSA 10 September 4, 2014

 Provide the codes that best describe the project’s type of need and reason (see Appendix B for 

“Lists of Codes”).

 Indicate if the project is to install new infrastructure to meet current population demands, replace 

old infrastructure, expand or upgrade existing infrastructure (such as treatment plants to meet 

current population demands) or rehabilitate existing infrastructure. 

 Indicate if the project is needed now to protect public health or is not needed now but will be 

necessary to continue providing safe drinking water within the next 20 years.

 Provide design capacity when applicable -- i.e., millions of gallons per day (MGD) for treatment 

and pumping; millions of gallons (MG) for storage; the diameter and number of feet of 

distribution or transmission lines; and the size and number of backflow prevention 

devices/assemblies, lead service lines, valves and water meters. EPA will use these parameters to 

model project costs.

 If available, provide the capital cost estimate and year and month (if known) of the estimate. EPA 

will use this information to assign the cost of the project. The year and month are important 

because they will allow EPA to account for differences in the value of money over different years 

and to convert all costs to a common year.

 Provide an estimate of the total length of pipe in the water system. This information will only be 

required for water systems that submit pipe projects but do not have independent documentation 

of need for these projects (i.e., planning document, sanitary survey or leak and break records). It 

is expected that not all systems will need to provide this inventory information due to submitting 

pipe projects supported by independent documentation.

 Indicate the type of documentation using EPA’s “Lists of Codes” that explains why the project is 

needed and, if an existing cost estimate (developed for other purposes independent of the 

DWINSA) is available, indicate the documentation that explains the breakdown of the cost. This 

will verify the cost for the project. NOTE: EPA discourages systems or states from developing

new cost estimates solely for the purposes of the 2015 DWINSA. For needs identified without 

independent cost estimates, the Agency instead will rely on extrapolations from cost models that 

are based on extensive independently-documented cost estimates.

 Help verify that adequate documentation of the need has been submitted.

 Help determine if the project is an allowable need.

 Help gauge cost-reasonableness.

The data collection instrument contains optional worksheets where respondents can record information 

about the water system’s existing infrastructure, such as information on storage tanks, pumps and pipe 

material as well as the age and condition of the infrastructure. This information will not be entered into 

the DWINSA data system. The worksheets are only provided as a helpful tool for a respondent to 

inventory all of a water system’s assets and assess any infrastructure needs that are not yet part of the

system’s formal planning documents.

For respondents to the 2015 DWINSA that did not participate in the 2011 DWINSA, the states will 

provide a data collection instrument with the water system characteristics information. The respondent 

will be asked to populate this document with a list of all the system’s planned capital improvement 
ICR for 2015 DWINSA 11 September 4, 2014

projects for the survey period of January 1, 2015 to December 31, 2034. The system must provide 

documentation and ensure that all projects meet policy requirements established for the 2015 DWINSA.

For respondents to the 2015 DWINSA that reported projects in the 2011 DWINSA, states will provide 

them with a list of all the projects that were submitted in response to the 2011 DWINSA. EPA will 

provide the 2011 project list to each state for each water system selected for both surveys. The respondent

will be asked to update the list by correcting any old information (e.g., cost estimate) and deleting projects 

that are completed or no longer needed. The respondent will also add any new projects that were not 

included in the 2011 DWINSA. All projects must meet documentation and policy requirements 

established for the 2015 DWINSA.

The respondent’s representative is also asked to provide his or her name, title, address, phone number and 

e-mail address. This information is requested in case EPA or the state must contact the respondent for 

clarification or explanation of any response.

The respondent is asked to attach documentation for all needs and costs reported in the 2015 DWINSA or 

to refer to applicable documentation previously submitted to EPA for the 2011 DWINSA. Systems are 

encouraged to provide inventory data on their systems. Only where noted above will the inventory data be 

required. 

The data collection instrument and Lists of Codes are attached as Appendix B.

A.4.b.ii Respondent Activities 

2015 DWINSA – Systems Serving More Than 3,300 Persons

To complete the data collection instrument, the following activities are anticipated for CWSs serving 

more than 3,300 persons:

 Participate in an informational telephone call. Respondents will receive a call from the state 

describing the purpose of the DWINSA, the information that will be requested and the timetable 

for completing and returning the data collection instrument.

 Read the cover letter. Respondents will review the cover letter and instructions accompanying

the data collection instrument.

 Collect and copy supporting documentation. Respondents will locate the necessary supporting 

documentation in system files and copy it.

 Call for technical assistance. Respondents will call their state contacts for technical assistance, 

if necessary. 

 Complete the data collection instrument. Respondents will discuss current needs with the state 

and complete the data collection instrument. An estimate of total amount of pipe in the system

must be provided if any pipe project is submitted without independent documentation of need 

(e.g., a planning document). 

 Respond to call back from the state about the status of 2015 DWINSA. Respondents who do 

not provide information to the states in a timely manner will be contacted by the state to provide a 

brief report on the status of the 2015 DWINSA response.
ICR for 2015 DWINSA 12 September 4, 2014

2015 DWINSA – State Activities

For this burden estimate, EPA assumes all states will participate in certain “up-front activities” where the 

measure of the activity burden is on an “hours per state” basis and the combined burden on all states is 

calculated by multiplying by the 56 participating states.

The burden of additional state activities is measured on an “hours per system” basis and the combined 

burden on all states is calculated by multiplying the number of systems being sampled in the survey. The 

hours per system burden differs between systems serving 50,000 or more people and systems serving less 

than 50,000 persons. The combined additional burden on all states from surveying the larger systems is 

calculated by multiplying the hours per system burden of these systems by 612 – the total number of the 

larger systems being sampled in the survey. The combined additional burden on all states from 

surveying the smaller systems (serving 3,300 to 49,999 people) is calculated by multiplying the hours per 

system burden of these systems by 2,247 - the total number of these smaller systems being sampled in the 

survey. 

The total burden on all states is calculated by adding the combined burden based on “hours per state” with 

the combined burden based on hours per system for all systems to be surveyed.

State Up-Front Activities

This first activity category includes the states’ “fixed burden” for helping EPA prepare for the 

2015 DWINSA. 

– Participate in training and other pre-survey efforts. This activity includes 

participating in training sessions offered by EPA and becoming familiar with the survey 

design and policies. In addition, it includes activities such as reviewing the draft data 

collection instrument.

– Help EPA verify SDWIS data. There are several important variables for which SDWIS 

data must be verified. Critical inventory data for the water systems being surveyed will 

need to be reviewed. Such data include the public water system identification number 

(PWSID), system name, address, telephone numbers (if any), primary source, population 

served, number of service connections, whether the water system is publicly or privately 

owned and whether the water system purchases/sells water from/to another water system. 

To help with this verification activity, EPA will provide the information that must be 

reviewed in electronic form.

– Perform miscellaneous administrative activities. States will perform various 

administrative duties prior to the 2015 DWINSA (e.g., establishing system files). In 

addition, state management will explain the 2015 DWINSA to staff and allocate 

resources. 

State Data Collection Activities for Systems Serving more than 3,300 Persons

States will conduct the following activities for CWSs serving more than 3,300 persons during the 

data collection phase of the 2015 DWINSA:

– E-mail survey package to water systems. States will provide each system in the 2015 

DWINSA with a survey package, which will be delivered via e-mail.

– Telephone systems to ensure participation and provide instructions. To improve 

response rates, states will telephone the water systems early in the process to ensure that 
ICR for 2015 DWINSA 13 September 4, 2014

they have received the survey package and understand how to complete the data 

collection instrument.

– Provide technical assistance. States will provide technical assistance to systems by 

answering their questions about the data collection instrument and how needs should be 

represented.

– Call systems that do not return the data collection instrument by a certain date. To 

improve response rates, states will telephone systems that have not returned their 

assessment by a specific date to encourage participation.

– Review completed data collection instruments and documentation. The data 

collection instrument will be returned directly to the state. State personnel will have the 

opportunity to review the information on the data collection instrument, as well as any 

accompanying documentation. The state’s review will provide the first quality 

assurance/quality control check. 

– Discuss results with EPA. After the state reviews the submission and documentation, the 

state forwards the data to EPA for review and data entry. EPA performs a second quality 

assurance/quality control check to ensure all data are documented and allowable. Any 

issues regarding the project descriptions or adequacy of the documentation of the data 

will be resolved by EPA and the state. States are provided access to the data system and 

are able to verify that the data have been entered into the data system.

Small CWSs (systems serving 3,300 and fewer people)

As discussed above, EPA will not collect data from small systems. The needs of these systems will be 

based on the results of the 2007 Assessment. EPA will adjust these estimates to 2015 dollars for the 2015 

DWINSA.

NPNCWSs

EPA will base the needs of NPNCWSs on the 1999 DWINSA results. EPA will adjust these estimates to 

2015 dollars for the 2015 DWINSA.

American Indian and Alaska Native Village Water Systems 

EPA will base the needs of Alaska Native Village and American Indian water systems on the results of 

the 2011 Native American DWINSA. EPA will adjust these estimates to 2015 dollars for the 2015 

DWINSA.
ICR for 2015 DWINSA 14 September 4, 2014

A.5 INFORMATION COLLECTED: AGENCY ACTIVITIES, COLLECTION 

METHODOLOGY AND INFORMATION MANAGEMENT

A.5.a Agency Activities 

A.5.a.i EPA and Contractor Activities

Many of the EPA activities described here will be conducted by contractors with EPA oversight/technical 

direction. For example, EPA will oversee contractor acceptance of survey submissions and subsequent 

data analysis. For purposes of describing Agency activities related to the 2015 DWINSA, contractor effort 

is not distinguished from EPA effort. Separate estimates for contractor burden and cost will be provided 

in Section A.6.c. In addition, Section B.1.c describes the contractor’s role. 

Up-Front Activities

The following pre-assessment activities will be conducted:

 Revise the data collection instrument. EPA is revising the data collection instrument based on 

lessons learned during the previous DWINSAs and state input from a May 2014 Workgroup 

meeting. This task will include developing materials for water system use and for state use in 

supporting water systems. 

 Train state participants. To ensure that state staff understand every aspect of the 2015

DWINSA, EPA will conduct five training sessions at locations across the country. The training 

will help ensure consistent responses across the country, high response rates and efficient use of 

staff. 

 Select 2015 DWINSA respondents. The Agency will drop a random selection of 25 percent of 

the systems serving 3,301 to 100,000 people that participated in the 2011 DWINSA. The Agency 

will draw a random sample to replace those systems in the survey for the 2015 DWINSA. The 

Agency will also update inventory numbers for water systems serving more than 3,300 people. 

Section B.2.c. describes the precision targets in more detail.

 Update data system. EPA will update the data system used for the 2011 DWINSA to store and 

analyze data. The data system will produce the necessary statistical reports for EPA, Congress 

and states. The data system will also allow EPA and state offices to have access to the data.

 Send data collection instruments. This will include prepopulating an electronic data collection 

instrument with water system inventory information and a list of projects reported in the 2011 

DWINSA (for systems that participated in the 2011 DWINSA) and sending the survey packages 

via e-mail to the states. Survey packages will include the prepopulated data collection instrument

for each water system selected in the 2015 DWINSA, Lists of Codes for the survey, instructions 

and a cover letter from EPA.
ICR for 2015 DWINSA 15 September 4, 2014

Data Collection Activities

EPA will conduct the following activities during the data collection phase of the 2015 DWINSA:

 Provide technical assistance. The Agency will provide technical assistance to water systems and

states to promote consistent responses across the country.

 Review completed data collection instruments. EPA will review the completed data collection 

instruments to ensure that all data are documented and allowable.

 Maintain the data. EPA will enter DWINSA data into the data system and perform quality 

assurance/quality control checks of data entry.

 Communicate results of review to the state. EPA will communicate the results of each survey 

submittal review to the states via a website that shows the updated project table and comment 

codes indicating the changes made. EPA Regional staff will also be able to view the data for 

states in their respective Regions.

A.5.b Collection Methodology and Management 

This section discusses the steps that EPA has taken to ensure that the information being collected will be 

accurate, reliable and retrievable. This methodology was developed using experience gained in 

conducting the previous DWINSAs. EPA has incorporated into this methodology comments and advice 

from EPA staff involved with those assessments. 

Development of Data Collection Instrument

Appendix B contains the data collection instrument. EPA has developed the 2015 DWINSA approach and 

the data collection instrument with the assistance of a workgroup. As is explained in Section A.3.c, the 

workgroup includes EPA Headquarters, EPA Regions and state representatives. The 2015 DWINSA 

approach and many of the refinements to the data collection instrument were based on experience in 

conducting the 1995, 1999, 2003, 2007 and 2011 DWINSAs. One change to the data collection 

instrument for the 2015 DWINSA is that it will only be administered electronically, whereas in the past 

respondents had the option of receiving printed or electronic data collection instruments. Another change, 

which can be found in EPA’s Lists of Codes, is the deletion of certain types of needs from the list that 

water systems use in filling out the survey instrument (see Appendix B). These types of needs are being 

removed from the 2015 DWINSA pursuant to discussions with states in which they were identified as 

having very little relative impact on survey results. Note that these needs are stricken out on the list rather 

than simply dropped; this was done to help facilitate the re-review in the 2015 DWINSA of submissions 

from systems’ surveys in 2011 when these codes were still being used.

EPA is also modifying the approach for collecting information on “green” and climate readiness attributes 

of infrastructure projects for the 2015 DWINSA. EPA will not include questions about these projects in 

the data collection instrument. Instead, EPA will explore streamlined approaches that might enable the 

Agency, during the Survey review process, to identify and flag projects that are likely to have “green,” 

climate readiness or climate resilience attributes. 

The format and content of the data collection instrument will otherwise remain largely unchanged from 

the 2011 DWINSA. Section B.2.c.ii describes the steps taken to ensure that the data collection instrument 

will be an effective tool for retrieving the information EPA needs to meet the 2015 DWINSA objectives.
ICR for 2015 DWINSA 16 September 4, 2014

Methodology for 2015 DWINSA – CWSs Serving More Than 3,300 Persons

Most systems serving more than 100,000 persons have CIPs or similar documents that summarize their 

projects. Therefore, these systems are generally able to provide accurate information on their needs and,

for some projects, accurate estimates on the associated cost. A data collection instrument will be sent to 

states for every CWS that serves more than 100,000 persons. Clarifying information for completing the 

data collection instrument will be available from EPA. 

The experience of states that participated in the previous DWINSAs indicates that most systems serving 

3,301 to 100,000 persons could provide reliable data on their needs and a large portion of these systems

could provide at least some cost estimates for meeting those needs. 

Also, water systems that participated in the 2011 DWINSA and are selected to participate in the 2015

DWINSA will receive a copy of their project submissions from the 2011 DWINSA. These water systems 

will be able to update the information on the list and add new projects to the data collection instrument. 

States will provide technical support to the water systems participating in the 2015 DWINSA. EPA will 

also offer technical support to state and water system personnel.

EPA will send the data collection instrument to the states to forward on to the water systems. Water 

systems will return the completed data collection instruments to the state. The state will then forward the 

data collection instrument and supporting documentation to EPA for review and data entry. EPA will 

perform a second quality assurance/quality control check to ensure that all infrastructure projects are 

documented and allowable. EPA will enter the data into the data system. Projects or cost estimates that 

are not documented will be identified in the data system as lacking documentation. If the system or state 

does not provide documentation, the project or cost estimate will be deleted from the 2015 DWINSA. 

EPA will offer technical support to state personnel to assist with the completion of each of these steps.

For projects that do not have cost estimates, EPA will model the costs.

Methodology for 2015 DWINSA – CWSs Serving 3,300 and Fewer Persons

Data will not be collected in the 2015 DWINSA from CWSs serving 3,300 and fewer persons. Their 

needs will be based on data collected during the 2007 DWINSA and updated to 2015 dollars.

Methodology for 2015 DWINSA – NPNCWSs

Data will not be collected in the 2015 DWINSA from NPNCWSs. Their needs will be based on data 

collected during the 1999 DWINSA and updated to 2015 dollars.

Methodology for American Indian and Alaska Native Village Water Systems 

EPA conducted a survey of American Indian and Alaska Native Village water systems in the 2011 

DWINSA. EPA will not collect data in the 2015 DWINSA from American Indian and Alaska Native 

Village water systems. Their needs will be based on data collected during the 2011 Native American 

DWINSA and updated to 2015 dollars.

Data Quality

It is important that the results of the DWINSA be as uniform as possible across the country. Toward this 

end, EPA will take the following steps:

 EPA will establish a uniform set of assumptions or criteria for state, EPA Regions, EPA 

Headquarters and contractor staff to evaluate data provided by systems. 
ICR for 2015 DWINSA 17 September 4, 2014

 EPA will provide training to all those involved in the DWINSA to ensure that the assumptions 

and procedures are clear and understood. 

 EPA will provide quality control reviews of each data collection instrument submitted to ensure 

compliance with DWINSA policies and accuracy of data. 

Among the most important steps in quality assurance is training. EPA will provide training sessions for 

state and EPA Regions involved in the 2015 DWINSA. The training sessions will be designed to enable 

state and EPA Regions to review completed data collection instruments and respond to questions from 

systems on the projects to be included in the survey response and related project documentation. The 

training will emphasize the following elements:

 Identifying the capital improvements associated with source, treatment, transmission, distribution

and storage.

 Discussing policies and documentation requirements.

 Completing the 2015 DWINSA data collection instrument. 

EPA will develop materials for distribution to state and EPA Region personnel who are unable to attend 

training sessions. 

In addition to the training sessions, EPA will provide technical support to state, EPA Region and water 

system personnel. It is anticipated that this support will primarily consist of providing information to the 

EPA Regions and states, which will then provide technical support to the systems. However, technical 

support will be available to systems in states that have chosen not to provide their own technical 

assistance. 

Data quality will be assured by implementing the following mechanisms throughout the gathering and 

processing phases of the information collection:

 Adequate documentation. EPA has requested documentation of needs and costs, when cost 

documentation is available, to ensure the accuracy and reliability of the data. Acceptable forms of 

documentation of needs and costs are included on List 4 of the Lists of Codes. EPA will not 

accept needs or costs without adequate documentation. EPA will emphasize to respondents that 

they are not expected to develop cost estimates for the purposes of the 2015 DWINSA. The costs 

of projects without a cost estimate will be modeled by EPA. 

 Provide an estimate of the total length of pipe in the water system. This information will only 

be required for water systems that submit projects for rehabilitation or replacement of pipe that 

are not independently documented (e.g., planning document or sanitary survey). It is expected 

that not all systems will need to provide this information. 

 Receipt control. The primary objective of the receipt control system will be to ensure that 

completed forms submitted by respondents (or forwarded by states) are logged in promptly and 

given proper chain of custody. A second objective is to provide states with the data needed to 

monitor cumulative receipts by date to identify potential problems with the response rate. Such 

response rate problems could necessitate action. See Section B.2.c.ii for EPA’s method for 

improving the response rate. States that receive data collection instruments from respondents will 

be trained in receipt control.
ICR for 2015 DWINSA 18 September 4, 2014

 Data review by states and EPA Regions. EPA will rely on the states and EPA Regions to help 

ensure data quality. Fifteen states are expected to opt out of participating in the statistical portion 

of the 2015 DWINSA (i.e., collecting data from systems serving 3,301 to 100,000 persons). 

However, all states that have systems serving more than 100,000 persons are expected to 

participate in the census portion of the survey. EPA will ask the Association of State Drinking 

Water Administrators (ASDWA) to communicate with the state drinking water program 

administrators to encourage their participation. EPA believes that state review is important in 

ensuring nationally consistent results because the states have more frequent communications with 

systems and possess a better understanding of each particular system’s needs. Therefore, state 

personnel will have the opportunity to review the information on the form, as well as any 

accompanying documentation. When necessary, the states will contact the water system to ask for 

clarifying information.

 Survey review and data entry. EPA will screen the submitted electronic data collection 

instruments for completeness and review projects to ensure that they are allowable and 

adequately documented based on survey policies. To reduce the review time for water systems 

that participated in the 2011 DWINSA, EPA will compare the responses of the 2015 DWINSA 

with those of the 2011 DWINSA and conduct a thorough review of the projects flagged as 

requiring a complete review. Projects that are needed in each 20-year survey period and that 

remain unchanged from the 2011 survey will not require a complete review unless that project is 

impacted by another project that is added or changed. Reviewers will also assign comment codes 

to projects to describe any changes made to the data. Data from the data collection instruments 

will be entered into the database only after they have passed the initial screening. As data are 

entered, an automatic data entry program will provide reasonable bounds checking and data 

verification. The program will signal if an entry is out of the allowable range or is an invalid entry

for that data field. All such signals will be investigated and resolved.

 Data systems. EPA updated a Web-based data system for the 2007 and 2011 DWINSAs that will 

be used for the 2015 DWINSA. The Web-based system includes a data entry interface that allows 

the Agency and its contractor to input data and allows states and EPA Regions to access, 

download, verify and suggest modifications to their data (www.DWNeeds.com). EPA will use a 

commercial “off the shelf” program, Microsoft Access, to manage the information. The data 

system will provide the following functions:

– Data entry through the user interface or batch upload.

– Data verification through bounds checking.

– A password-protected data modification interface.

– Data access for states and EPA Regions for review and verification of their data.

– Predefined summary and statistical reports.

 Cost reasonableness ranges. EPA will develop “cost reasonableness ranges” to help verify the 

accuracy of the data and identify projects for further review.

Public Access to Data

The Agency’s policy is to make the fullest possible disclosure of information without unjustifiable 

expense or unnecessary delay to the requester. Once the final Report to Congress has been submitted, the 

public will be given access to assessment data in accordance with EPA’s policies and procedures for 

Freedom of Information Act (FOIA) requests. However, as a matter of policy, EPA will not disclose the 

identity of any respondent to the 2015 DWINSA. EPA will develop standard report formats for providing 

data to the public. 
ICR for 2015 DWINSA 19 September 4, 2014

A.5.c Small Entity Flexibility 

In designing the 2015 DWINSA methodology, EPA has taken small systems’ relatively limited technical 

capabilities and financial resources into account. EPA’s experience with the previous DWINSAs has 

shown that some small systems lack the resources and technical ability to complete the data collection 

instruments. Small CWSs (those serving 3,300 and fewer persons) will not be included in the surveying 

for the 2015 DWINSA. EPA will use the results from the 2007 DWINSA adjusted to 2015 dollars. For 

NPNCWSs, EPA will use the 1999 DWINSA results, adjusted to 2015 dollars, as the basis for the 2015

DWINSA estimates. 

For the 2011 DWINSA, EPA conducted a census of all American Indian water systems that served more 

than 10,000 persons (there were no Alaska Native Village water systems that serve more than 10,000 

persons) and selected a random sample of American Indian and Alaska Native Village systems serving 

10,000 and fewer persons. To reduce the burden on these systems and EPA, the Agency will use the 

results from the 2011 DWINSA as the basis for the 2015 DWINSA estimates for these water systems.

A.5.d Collection Schedule 

The current schedule assumes EPA would receive OMB approval for data collection by January 2015. 

The schedule will be adjusted based on the final approval date. EPA will send data collection instruments 

to states as soon as possible after OMB approval. All systems participating in the 2015 DWINSA will be 

asked to complete and return the data collection instruments to their state within 1 month of receipt.

To facilitate efficient data entry by EPA, the Agency will ask the states to submit data for one-third of the 

systems within three months after data collection begins. Data for two-thirds of the systems will be due 

within six months and all data will be due within nine months. Exhibit A-5-1 summarizes the major 

collection milestones.

Exhibit A-5-1 Collection Schedule

Task Date

EPA Tentatively Selects Systems to be Included in State Samples September 2014

Training Sessions for States and EPA Regions September - October 2014

Information Collection Request Submitted to OMB December 2014

Electronic Delivery of Data Collection Instruments to States February 2015

Date by which Systems Are to Return the Data Collection Instrument 

to States

March 2015

1/3 of Sent Data Collection Instruments Returned by States to EPA May 2015

2/3 of Sent Data Collection Instruments Returned by States to EPA August 2015

All Sent Data Collection Instruments Returned by States to EPA November 2015

No New Projects Will Be Accepted by EPA December 2015

No New Information on Submitted Projects Will Be Accepted by EPA February 2016

All Information in the Data System Finalized August 2016

Report to Congress Due February 2, 2017
ICR for 2015 DWINSA 20 September 4, 2014

A.6 ESTIMATING THE BURDEN AND COST OF THE COLLECTION

A.6.a Respondent Burden 

Modifications to the implementation of the 2015 DWINSA will change how burden is distributed among 

the systems and states from past DWINSAs. For the 2015 DWINSA, the majority of the respondents will 

be updating their submittal from 2011. It is anticipated this will reduce the burden for both entities. In 

addition, all responses will be submitted in electronic format, which will reduce the burden associated 

with EPA or states distributing the survey packages to systems. 

EPA estimates that there will be 612 systems 

serving more than 100,000 people and 308 systems 

serving 50,001 to 100,000 people (231 of which 

participated in the 2011 DWINSAs and 77 of which 

did not). EPA estimates that 1,939 systems serving 

3,001 to 50,000 people will participate in the 2015 

DWINSA and approximately 75 percent of these 

systems (1,454) also participated in the 2011 

DWINSA. This breakdown is used to calculate the 

average burden per system in the sections that 

follow.

A.6.a.i Burden to Community Water Systems 

The annual water system burden for the 2015

DWINSA is estimated to be 3,956 hours (a total of 

15,822 hours over the full four-year project effort). 

Exhibit A-6-6 shows the breakdown of the total 

burden hours for CWSs by system size in the 2015 DWINSA. The basis for the burden estimates are 

detailed below.

2015 DWINSA – CWSs Serving More Than 50,000 Persons

The respondent burden for the systems serving more than 50,000 persons consists of systems’ burden for 

completing the data collection instrument. EPA estimates that the total unit burden is 6.48 hours per 

system. Exhibit A-6-1 shows the unit burden for 920 systems serving more than 50,000 persons. 

 Participate in informational phone call. All systems will participate in an informational phone 

call with the state. For systems that participated in the 2011 DWINSA, each informational call 

should last about 15 minutes (0.25 hours). 

EPA anticipates that systems that did not participate in the 2011 DWINSA will require more time 

on the phone call to understand the process. Each informational call should last about 20 minutes 

(0.33 hours). 

Consequently, the average burden per system is as follows:

[0.25 x (612 + (0.75 x 308))/(612 + 308)] + [0.33 x (0.25 x 308)/(612 + 308)] = 0.26 hrs/system

EPA anticipates that management staff will take the call at half of the systems and technical staff 

will take the call at the other half.

Respondents by Water System Size

 Systems serving more than 50,000 persons 

= 920 systems.

o 612 serving more than 100,000 and 

participated in the 2011 DWINSA.

o 231 serving 50,001-100,000 and

participated in the 2011 DWINSA.

o 77 serving 50,001-100,000 and did not 

participate in the 2011 DWINSA.

 Systems serving 3,301-50,000 persons = 

1,939 systems.

o 1,454 serving 3,301-50,000 and

participated in 2011 DWINSA.

o 485 serving 3,301-50,000 and did not 

participate in 2011 DWINSA.
ICR for 2015 DWINSA 21 September 4, 2014

 Read cover letter. EPA anticipates that systems that participated in the 2011 DWINSA will 

require less time to read the cover letter and data collection instructions because they will already 

be familiar with the process and will only need to become familiar with aspects of the survey that 

have changed. EPA estimates that the burden for each of these systems is 45 minutes (0.75 hours) 

and breaks down as follows: 

– A manager will receive the 2015 DWINSA, read the cover letter and review the 

instructions and other materials. The estimated time for managers to perform these 

activities is 15 minutes (0.25 hours). 

– Technical staff will read the cover letter and data collection instructions in detail. EPA 

estimates that the burden for this activity is 30 minutes (0.5) hours per system.

EPA estimates that systems that did not participate in the 2011 DWINSA will require 1.5 hours to 

read these materials. This estimate breaks down as follows: 

– A manager will receive the 2015 DWINSA, read the cover letter and review the 

instructions and other materials. The estimated time for managers to perform this role is 

30 minutes (0.50 hours). 

– Technical staff will read the cover letter and data collection instructions in detail. EPA 

estimates that the burden for this activity is 1.0 hour per system.

Thus, the total unit burden is:

[0.75 x (612 + (0.75 x 308))/(612 + 308)] + [1.5 x (0.25 x 308)/(612 + 308)] = 0.81 hrs/system

 Collect and copy supporting documentation. The time required to review system files and to 

collect and copy supporting documentation will vary greatly. EPA anticipates that systems that 

participated in the 2011 DWINSA will use much of the same documentation that was collected 

and submitted for the previous DWINSA with limited modifications or updates. Therefore, EPA 

estimates that the time for these systems to collect and copy supporting documentation will be 

reduced from previous years. EPA estimates that it will take 1.0 hour at 50 percent of the systems, 

2.0 hours at 25 percent of the systems and 4.0 hours at 25 percent of the systems. Thus, the 

average time per system is as follows:

(1.0 x 0.5) + (2.0 x 0.25) + (4.0 x 0.25) = 2.0 hrs/system

For systems that did not participate in the 2011 DWINSA, EPA estimates that it will take 1.5 

hours at 30 percent of the systems, 2.5 hours at 30 percent of the systems, four hours at 30 percent 

of the systems and 16 hours at 10 percent of the systems. Thus, the average time per system is as 

follows:

(1.5 x 0.30) + (2.5 x 0.30) + (4 x 0.30) + (16 x 0.10) = 4 hrs/system

The total average time per system is:

[2.0 x (612 + (0.75 x 308))/(612 + 308)] + [4 x (0.25 x 308)/(612 + 308)] = 2.16 hrs/system

Half of this time will be spent by technical staff and half will be spent by clerical staff.

 Call for technical assistance. Many systems will call states for technical assistance. In 

developing the burden estimate for this activity, EPA assumes that the number of requests for 
ICR for 2015 DWINSA 22 September 4, 2014

assistance will equal 100 percent of the number of systems. (This estimate considers the 

likelihood that some systems will call more than once, while some will not call at all.) EPA also 

assumes that each call will be placed by technical staff.

EPA anticipates that systems that participated in the 2011 DWINSA will require less technical 

assistance than those that did not participate in the 2011 DWINSA. Therefore, EPA estimates that 

all questions from systems that participated in the 2011 DWINSA will be readily answerable and 

the state will not need to conduct any additional research and will be able to answer the question 

during the initial call. That initial call is estimated to average 15 minutes (0.25 hours).

EPA estimates that the burden for systems that did not participate in the 2011 DWINSA is 20

minutes (0.33 hours) and break down as follows:

– About 50 percent of the questions will be readily answerable” and the state will not need 

to conduct any additional research and will be able to answer the question during the 

initial call that will average 15 minutes (0.25 hours).

– About 50 percent of the questions will require the state to perform research and call the 

system back. In this case, EPA estimates that the total burden for the two calls is 25

minutes (0.42 hours).

[(0.25 x 0.50) + (0.42 x 0.50)] = 0.34 hrs/system

The total average burden per system is:

[0.25 x (612 + (0.75 x 308))/(612 + 308)] + [0.34 x (0.25 x 308)/(612 + 308)] = 0.26 hrs/system

 Complete data collection instrument. The burden to systems to complete the data collection 

instrument will vary depending on whether the system participated in the 2011 DWINSA. The 

2011 DWINSA participants will have a relatively low burden because EPA expects that a large 

portion of the information in the 2011 survey will carry over to the 2015 DWINSA. Thus, 2011

DWINSA participants will only update their needs and documentation rather than identify their 

needs anew. 

EPA estimates that technical staff at systems that participated in the 2011 DWINSA will require 

two hours to update the 2011 survey and complete the project table of the data collection 

instrument. Management is expected to take 18 minutes (0.30 hours) to review the completed data 

collection instrument for accuracy. Clerical staff is anticipated to take 18 minutes (0.30 hours) to 

provide support to the technical staff. Thus, the total unit burden to systems that participated in 

the 2011 DWINSA is approximately 2.6 hours per system. 

EPA estimates that technical staff at systems that did not participate in the 2011 DWINSA will 

take three hours to complete the project table of the data collection instrument. This estimate is 

consistent with EPA’s experience with the previous DWINSAs. Management is expected to take 

18 minutes (0.30 hours) to review the completed data collection instrument for accuracy. Clerical 

staff is anticipated to take one hour to provide support to the technical and managerial staff. Thus, 

the total unit burden to systems that did not participate in the 2011 DWINSA is approximately 4.3

hours per system.

The total average burden per system is as follows:

[2.6 x (612 + (0.75 x 308))/(612 + 308)] + [4.3 x (0.25 x 308)/(612 + 308)] = 2.74 hrs/system
ICR for 2015 DWINSA 23 September 4, 2014

 Respond to call back from state about status of 2015 DWINSA. For this burden estimate, 

EPA assumes each system will spend time responding to the state call(s) to request a status 

update on completing the survey’s questionnaire. EPA assumes that the average total time spent

by each system on responding to the state call(s) is 15 minutes (0.25 hours) per system. This does 

not include discussing technical questions, which is accounted for above. Rather, it includes time 

required for the system to provide the state with a brief report on the status of the 2015 DWINSA 

response.

Exhibit A-6-1 Estimated Average Unit Burden for Systems Serving More Than 50,000 

Persons

Activity

Estimated Burden (hours)

Management Technical Clerical Total

Participate in informational phone call 0.13 0.13 0.26

Read cover letter/data collection 

instructions 0.27 0.54 0.81

Collect supporting documentation 1.08 1.08 2.16

Call for technical assistance 0.26 0.26

Complete data collection instrument 0.30 2.08 0.36 2.74

Respond to call back from state 0.25 0.25

TOTAL 0.70 4.34 1.44 6.48

2015 DWINSA – CWSs Serving 3,301 – 50,000 Persons

Exhibit A-6-2 shows the unit burden for 1,939 systems serving 3,301 to 50,000 persons. EPA estimates 

that each of these systems will take a total of 5.09 hours to respond to the 2011 DWINSA.

 Participate in informational phone call. All systems will participate in an informational phone 

call with the state. For systems that participated in the 2011 DWINSA, each informational call 

should last about 15 minutes (0.25 hours). 

EPA anticipates that systems that did not participate in the 2011 DWINSA will require more time 

on the phone call to understand the process. Each informational call should last about 20 minutes 

(0.33 hours). 

Consequently, the average burden per system is as follows:

[(0.25 x 0.75) + (0.33 x 0.25)] = 0.27 hrs/system

EPA anticipates that management staff will take the call at half of the systems and technical staff 

will take the call at the other half.

 Read cover letter. EPA anticipates that systems that participated in the 2011 DWINSA will 

require less time to read the cover letter and data collection instructions because they will already 

be familiar with the process and will only need to become familiar with aspects of the survey that 

have changed. EPA estimates that the burden for each of these systems is 45 minutes (0.75 hours) 

and breaks down as follows: 
ICR for 2015 DWINSA 24 September 4, 2014

– A manager will receive the 2015 DWINSA, read the cover letter and review the 

instructions and other materials. The estimated time for managers to review these items is 

15 minutes (0.25 hours). 

– Technical staff will read the cover letter and data collection instructions in detail. EPA 

estimates that the burden for this activity is 30 minutes (0.50) hours per system.

EPA estimates that systems that did not participate in the 2011 DWINSA will require 1.5 hours to 

read these materials. This estimate breaks down as follows: 

– A manager will receive the 2015 DWINSA, read the cover letter and review the 

instructions and other materials. The estimated time for managers to review the cover 

letter is 30 minutes (0.50 hours).

– Technical staff will read the cover letter and data collection instructions in detail. EPA 

estimates that the burden for this activity is one hour per system.

Thus, the total unit burden is:

[(0.75 x 0.75) + (1.5 x 0.25)] = 0.94 hrs/system

 Collect and copy supporting documentation. The time required to review system files and to 

collect and copy supporting documentation will vary greatly. For instance, systems serving 3,301 

to 50,000 persons typically have less documentation than larger CWSs. Furthermore, EPA 

anticipates that systems that participated in the 2011 DWINSA will use much of the same 

documentation that was collected and prepared for the previous DWINSA with limited 

modifications or updates. Therefore, EPA estimates that the time for these systems to collect and 

copy supporting documentation will be reduced from previous years. EPA estimates that it will 

take approximately 45 minutes (0.75 hours) at 40 percent of these systems, 1.5 hours at 40 

percent of these systems and three hours at 20 percent of these systems. Thus, the average time 

per system that participated in the 2011 DWINSA is as follows:

[(0.75 x 0.40) + (1.5 x 0.40) + (3 x 0.20)] = 1.5 hrs/system

For systems that did not participate in the 2011 DWINSA, EPA estimates that it will take one

hour at 50 percent of the systems, two hours at 25 percent of the systems and four hours at 25 

percent of the systems. Thus, the average time per system is as follows:

[(1.0 x 0.5) + (2.0 x 0.25) + (4.0 x 0.25)] = 2.0 hrs/system

The total average time per system is:

[(1.5 x 0.75) + (2.0 x 0.25)] = 1.63 hrs/system

Half of this time will be spent by technical staff and half will be spent by clerical staff.

 Call for technical assistance. Many systems will call states for technical assistance. In 

developing the burden estimate for this activity, EPA assumes that the number of requests for 

assistance will equal 150 percent of the number of systems. (This estimate accounts for the fact 

that some systems will call more than once, while some will not call at all.) EPA also assumes 

that each call will be placed by technical staff.
ICR for 2015 DWINSA 25 September 4, 2014

EPA anticipates that systems that participated in the 2011 DWINSA will require less technical 

assistance than those that did not participate in the 2011 DWINSA. Therefore, EPA estimates that 

all questions from systems that participated in the 2011 DWINSA will be readily answerable and 

the state will not need to conduct any additional research and will be able to answer the question 

during the initial call. That initial call is estimated to average 15 minutes (0.25 hours).

EPA estimates that the burden for systems that did not participate in the 2011 DWINSA is 20 

minutes (0.34 hours) and breaks down as follows:

– About 50 percent of the questions will be readily answerable and the state will not need 

to conduct any additional research and will be able to answer the question during the 

initial call that will average 15 minutes (0.25 hours).

– About 50 percent of the questions will require the state to perform research and call the 

system back. In this case, EPA estimates that the total burden for the two calls is 25

minutes (0.42 hours).

[(0.25 x 0.50) + (0.42 x 0.50)] = 0.34 hrs/system

The total average burden per system is:

1.50 x [(0.25 x 0.75) + (0.34 x 0.25)] = 0.41 hrs/system

 Complete data collection instrument. The burden to systems to complete the data collection 

instrument will vary depending on whether or not the system participated in the 2011 DWINSA. 

The 2011 DWINSA participants will have a relatively low burden because EPA expects that a 

large portion of the information in the 2011 survey will carry over to the 2015 DWINSA. 

Consequently, 2011 DWINSA participants will only update their needs and documentation rather 

than identify their needs anew.

EPA estimates that technical staff at systems that participated in the 2011 DWINSA will require 1 

hour to update the 2011 survey and complete the project table of the data collection instrument. 

Management is expected to take 18 minutes (0.30 hours) to review the completed data collection 

instrument for accuracy. Thus, the total unit burden to systems that participated in the 2011 

DWINSA is approximately 1.3 hours per system.

EPA estimates that technical staff at systems that did not participate in the 2011 DWINSA will 

take two hours to complete the data collection instrument. This estimate is consistent with EPA 

experience with the previous DWINSAs. Management is expected to take 28 minutes (0.47 

hours) to review the completed data collection instrument for accuracy. Thus, the total unit 

burden to systems that did not participate in the 2011 DWINSA is approximately 2.47 hours per 

system.

The total average burden per system is as follows:

(1.3 x 0.75) + (2.47 x 0.25) = 1.59 hrs/system

 Respond to call back from state about status of 2015 DWINSA. For this burden estimate, EPA 

assumes each system will spend time responding to the state call(s) to request a status update on 

completing the survey’s questionnaire. EPA assumes that the average total time spent by each 

system on responding to the state call(s) is 15 minutes (0.25 hours) per system. This does not 

include discussing technical questions, which is accounted for above. Rather, it includes time 

required to provide the state with a brief report on the status of the 2015 DWINSA response.
ICR for 2015 DWINSA 26 September 4, 2014

Exhibit A-6-2 Estimated Average Unit Burden for Systems Serving 3,301 to 50,000 

Persons

Activity

Estimated Burden (hours)

Management Technical Clerical Total

Participate in informational phone call 0.135 0.135 0.27

Read cover letter/data collection 

instructions 0.31 0.63 0.94

Collect supporting documentation 0.81 0.81 1.63

Call for technical assistance 0.41 0.41

Complete data collection instrument 0.34 1.25 1.59

Respond to call back from state 0.25 0.25

TOTAL 0.79 3.49 0.81 5.09

Note: Numbers may not add due to rounding.

2015 DWINSA – CWSs Serving 3,300 and Fewer Persons

EPA will adjust the 2007 DWINSA need for CWSs serving 3,300 and fewer persons to 2015 dollars for 

the 2015 DWINSA and to reflect the 2015 number and sizes of these systems. There will be no burden for 

these systems. 

2015 DWINSA – NPNCWSs

EPA will adjust the 1999 DWINSA need for NPNCWSs to 2015 dollars for the 2015 DWINSA. There 

will be no burden for these systems. 

2015 Native American DWINSA – American Indian and Alaska Native Village Water Systems

EPA will adjust the 2011 DWINSA need for American Indian and Alaska Native Village Water Systems 

to 2015 dollars for the 2015 DWINSA and to reflect the 2015 number and sized of these systems. There 

will be no burden for these systems. 

A.6.a.ii Burden to States

As previously discussed, all states have committed to help EPA administer the 2015 DWINSA with at 

least the minimum of activities. The majority of states expected to opt out of the statistical portion of the 

survey have systems serving more than 100,000 persons; therefore, they would participate in the data 

collection phase of the 2015 DWINSA.

Up-Front Burden

This activity category includes the “fixed burden” for states to help EPA prepare for the 2015 DWINSA. 

The total burden for these activities is 110 hours per state, plus 0.2 hour per system assessed. Exhibit A-6-

3 summarizes this burden. 

 Participate in training and other pre-survey efforts. The burden for this activity is estimated at 

80 hours per state.

 Help EPA verify SDWIS data. Based on past experience, EPA estimates that verifying SDWIS 

data for systems in the sample will require approximately 12 minutes (0.2 hours) per system.
ICR for 2015 DWINSA 27 September 4, 2014

 Perform miscellaneous administrative activities. The burden for these activities should be 30 

hours per state.

Exhibit A-6-3 State Unit Burden for Up-Front Activities

Activity Estimated Burden

Participate in training and other pre-survey activities 80 hours/state

Help EPA verify SDWIS data 0.2 hours/system

Perform miscellaneous administrative activities 30 hours/state 

TOTAL 110 hours/state, plus 0.2 

hours/system

State Burden for CWSs Serving More Than 50,000 Persons

This section estimates the state burden for helping EPA conduct the 2015 DWINSA for systems serving 

more than 50,000 persons by providing technical assistance where needed, working with systems to 

identify their needs in 2015, calling systems that do not return the data collection instrument on time,

reviewing the completed data collection instrument and documentation and discussing the results with 

EPA. Although most of these systems will be able to answer the questions on the data collection 

instrument, states will provide them with clarifying information as necessary. The state burden for 

activities associated with the systems serving more than 50,000 persons is summarized in Exhibit A-6-4, 

which follows the activity descriptions.

 Telephone systems to ensure participation and provide instructions. EPA estimates that this 

preliminary phone call will take about 15 minutes (0.25 hours) per system that participated in the 

2011 DWINSA and about 20 minutes (0.33 hours) per system that did not participate in the 2011 

DWINSA. Thus, the average burden to states for each system is as follows:

[0.25 x (612 + (0.75 x 308))/(612 + 308)] + [0.33 x (0.25 x 308)/(612 + 308)] = 0.26 hrs/system

 E-mail survey package to systems. Each state will send the survey packet (provided by EPA) to 

systems via e-mail. EPA estimates that states will spend a total of 30 minutes drafting text for two 

e-mails: one to systems that participated in the 2011 DWINSA and one to systems that did not 

participate in the 2011 DWINSA. This amounts to approximately 0.01 minutes (0.0002 hours) per 

system. EPA anticipates that states will spend approximately five minutes (0.08 hours) compiling 

each e-mail, including addressing the e-mail to the correct recipient and attaching the correct 

files. EPA also estimates that approximately 10 percent of these e-mails will be returned to the 

states and states will require an additional five minutes (0.08 hours) to locate the correct recipient 

and resend the e-mail. Thus, the average burden to states for each system is as follows:

[0.0005 + 0.08 + (0.10 x 0.08)] = 0.09 hrs/system

 Provide technical assistance. In developing a burden estimate for this analysis, EPA assumes 

that the number of requests for technical assistance will equal 100 percent of the number of 

systems. (This estimate considers that some systems will call more than once while some will not 

call at all.)

EPA anticipates that systems that participated in the 2011 DWINSA will require less technical 

assistance than those that did not participate in the 2011 DWINSA. Therefore, EPA estimates that 
ICR for 2015 DWINSA 28 September 4, 2014

all questions from these systems will be readily answerable, requiring only 15 minutes (0.25 

hours) to answer.

EPA estimates that the burden to assist systems that did not participate in the 2011 DWINSA is

30 minutes (0.5 hours) and breaks down as follows:

– Of those that do require technical assistance, about 50 percent of their questions will be 

readily answerable, requiring only 15 minutes (0.25 hours) to answer.

– About 25 percent of their questions will entail limited research and follow-up, requiring 

30 minutes (0.50 hours) to answer, including time to call EPA with questions.

– About 25 percent of their questions will require the state to perform some research and 

will require one hour to answer.

Therefore, the state burden for providing technical assistance is estimated as:

[0.25 x (612 + (0.75 x 308))/(612 + 308)] + [0.5 x (0.25 x 308)/(612 + 308)] = 0.27 hrs/system

 Call back systems that do not provide information for the data collection instrument by a 

certain date. EPA assumes that the number of these “reminder” calls will equal 100 percent of 

the systems. This assumes that most (but not all) will need at least one reminder call and a few 

will need two or three. The average time for these calls is 20 minutes (0.33 hours) per system. 

This estimate includes the time to find the contact information and call the system as well as time 

to talk to the technical staff. This does not include answering technical questions, which is 

accounted for above. Rather, it includes locating the correct contact person and obtaining a brief 

report on the status of the 2015 DWINSA response.

 Review completed data collection instruments and documentation. The data collection 

instrument will be returned directly to the state for review. For some systems, the documentation 

is expected to be quite voluminous and reviewing it will be the most burdensome part of the 2015

DWINSA. The time required for this review is difficult to estimate. States may generate their 

own documentation for the 2015 DWINSA and, if they add distribution or transmission projects,

are required to ensure that the total pipe inventory section on the 2015 DWINSA is completed. 

For the 2015 DWINSA, the burden to states to review the data collection instrument for each 

system will vary depending on whether the system participated in the 2011 DWINSA. Based on 

discussions with the states concerning their level of effort in previous assessments, and based on 

the estimates for systems to complete the survey in previous assessments, EPA estimates that, on 

average, states will take 3.5 hours to review the submission for each system that participated in 

the 2011 DWINSA. This estimate reflects a lower burden than in the 2011 DWINSA because 

EPA expects the total time for states to review the data collection instrument for systems that 

participated in the 2011 DWINSA will be less than the time needed to review a newly developed 

data collection instrument. For the 2011 DWINSA it was assumed that all systems were preparing 

a new data collection instrument.

For systems that did not participate in the 2011 DWINSA, EPA estimates that a total of five hours

will be required for the state to review each data collection instrument. 

Thus, the average burden to states for each system is as follows:

[3.5 x (612 + (0.75 x 308))/(612 + 308)] + [5 x (0.25 x 308)/(612 + 308)] = 3.63 hrs/system
ICR for 2015 DWINSA 29 September 4, 2014

 Discuss results with EPA. To estimate the state burden for resolving questions on the completed 

data collection instruments, EPA made the following assumptions:

– EPA will have questions for the state on 50 percent of the completed data collection 

instruments. Some of these questions will actually apply to all systems. 

– Each question will take the state one hour to resolve.

Thus, the average burden to states for each system is as follows:

[0.5 x 1] = 0.50 hrs/system 

Exhibit A-6-4 State Unit Burden for Systems Serving More Than 50,000 Persons

Activity Estimated Burden

(hours per system)

Call to ensure participation 0.26

E-mail surveys to systems 0.09

Provide Technical Assistance 0.27

Call back systems that do not return the data collection instrument by 

a certain date 0.33

Review completed assessment forms and documentation 3.63

Discuss results with EPA 0.50

TOTAL 5.08

State Burden for CWSs Serving 3,301 – 50,000 Persons

This section estimates the state burden for helping EPA conduct the 2015 DWINSA for systems serving 

3,301 to 50,000 persons by telephoning systems to ensure participation, calling back systems that did not 

return the data collection instrument on time, reviewing the completed data collection instrument and the 

accompanying documentation and discussing the results with EPA. The state burden for activities 

associated with systems serving 3,301 to 50,000 persons is summarized in Exhibit A-6-5, which follows 

the activity descriptions.

 Telephone systems to ensure participation. EPA estimates that this preliminary phone call will 

take about 15 minutes (0.25 hours) per system that participated in the 2011 DWINSA and about 

20 minutes (0.33 hours) per system that did not participate in the 2011 DWINSA. Thus, the 

average burden to states for each system is as follows:

[(0.25 x 0.75) + (0.33 x 0.25)] = 0.27 hrs/system

 E-mail survey package to systems. Each state will send the survey packet (provided by EPA) to 

systems via e-mail. EPA estimates that states will spend a total of 30 minutes drafting text for two 

e-mails: one to systems that participated in the 2011 DWINSA and one to systems that did not 

participate in the 2011 DWINSA. This amounts to approximately 0.01 minutes (0.0002 hours) per 

system. EPA anticipates that states will spend approximately five minutes (0.08 hours) compiling 

each e-mail, including addressing the e-mail to the correct recipient and attaching the correct 

files. EPA also estimates that approximately 10 percent of these e-mails will be returned to the 
ICR for 2015 DWINSA 30 September 4, 2014

states and states will require an additional five minutes (0.08 hours) to locate the correct recipient 

and resend the e-mail. Thus, the average burden to states for each system is as follows:

[0.0005 + 0.08 + (0.10 x 0.08)] = 0.09 hrs/system

 Provide technical assistance. In developing a burden estimate for this analysis, EPA assumes 

that the number of requests for technical assistance will equal 150 percent of the number of 

systems. (This estimate accounts for the fact that some systems will call more than once while 

some will not call at all.)

EPA anticipates that systems that participated in the 2011 DWINSA will require less technical 

assistance than those that did not participate in the 2011 DWINSA. Therefore, EPA estimates that 

all questions from these systems will be readily answerable, requiring only 15 minutes (0.25 

hours) to answer.

EPA estimates that the burden to assist systems that did not participate in the 2011 DWINSA is

30 minutes (0.5 hours) and breaks down as follows:

– Of those that do require technical assistance, about 50 percent of their questions will be 

readily answerable, requiring only 15 minutes (0.25 hours) to answer.

– About 25 percent of their questions will entail limited research and follow-up, requiring 

30 minutes (0.50 hours) to answer, including time to call EPA with questions.

– About 25 percent of their questions will require the state to perform some research and 

will require one hour to answer.

Therefore, the state burden for providing technical assistance is estimated as:

1.5 x [(0.25 x 0.75) + (0.5 x 0.25)] = 0.47 hrs/system

 Call back systems that do not return the data collection instrument by a certain date. It is 

assumed that the number of these “reminder” calls will equal 150 percent of the systems. This 

assumes that most (but not all) will need at least one reminder call and some will need two or 

possibly three. The average time for these calls is 20 minutes (0.33 hours) per system. This does 

not include answering technical questions, which is accounted for above. Rather, it includes 

locating the correct contact person and obtaining a brief report on the status of the 2015 DWINSA

response.

[1.5 x 0.33] = 0.50 hrs/system

 Review completed data collection instruments and documentation. The data collection 

instrument will be returned directly to the state for review. For some systems, the documentation 

is expected to be quite voluminous and reviewing it will be the most burdensome part of the 2015

DWINSA. The time required for this review is difficult to estimate. States may generate their 

own documentation for the 2015 DWINSA and, if they add distribution or transmission projects,

are required to ensure that the total pipe inventory section on the 2015 DWINSA is completed. 

For the 2015 DWINSA, the burden to states to review the data collection instrument for each 

system will vary depending on whether or not the system participated in the 2011 DWINSA. 

Based on discussions with the states concerning their level of effort in previous assessments, and 

based on the estimates for systems to complete the survey in previous assessments, EPA 

estimates that, on average, states will take three hours to review the submission for each system 
ICR for 2015 DWINSA 31 September 4, 2014

that participated in the 2011 DWINSA. This estimate reflects a lower burden to the state than in 

the 2011 DWINSA because EPA expects the total time for states to review the data collection 

instrument for systems that participated in the 2011 DWINSA will be less than the time needed to 

review a newly developed data collection instrument. For the 2011 DWINSA, it was assumed that 

all systems were preparing a new data collection instrument.

For systems that did not participate in the 2011 DWINSA, EPA estimates that a total of 4.25 

hours will be required for the state to review each data collection instrument. 

Thus, the average burden to states for each system is as follows:

[(3 x 0.75) + (4.25 x 0.25)] = 3.31 hrs/system

 Discuss results with EPA. To estimate the state burden for resolving questions on completed 

data collection instruments, EPA made the following assumptions:

– EPA will have questions for the state on 50 percent of the completed data collection 

instruments. Some of these questions will actually apply to all systems.

– Each question will take the state one hour to resolve.

Thus, the average burden to states for each system is as follows:

[0.5 x 1] = 0.50 hrs/system 

Exhibit A-6-5 Estimated State Average Unit Burden for Systems Serving 3,301 to 50,000 

Persons

Activity Estimated Burden

(hours per system)

Telephone systems to ensure participation 0.27

E-mail surveys to systems 0.09

Provide technical assistance 0.47

Call back systems that do not return the data collection instrument by 

a certain date 0.50

Review completed data collection instruments and documentation 3.31

Discuss results with EPA 0.50

TOTAL 5.14
ICR for 2015 DWINSA 32 September 4, 2014

State Burden for CWSs Serving 3,300 and Fewer Persons

The 2015 DWINSA will use the 2007 DWINSA need for CWSs serving 3,300 and fewer persons 

adjusted to 2015 dollars. There will be no state burden for these CWSs.

State Burden for NPNCWSs

The 2015 DWINSA will use the 1999 DWINSA need for NPNCWSs, adjusted to 2015 dollars. There will 

be no state burden for these CWSs.

A.6.b Respondent Costs 

A.6.b.i Costs to Community Water Systems 

Exhibit A-6-6 summarizes the burden and costs to water systems. Total costs are estimated at $603,853, 

which consists solely of labor costs. There are no operation and maintenance (O&M) costs or capital costs 

associated with the collection. 

CWS labor costs are based on the number of burden hours multiplied by the average hourly wage rate, 

including overhead. The average hourly wage rate is the rate taken from a 2003 EPA document titled 

Labor Costs for National Drinking Water Rules. The quoted rate was $26.05 in 2003 dollars for systems 

serving 50,000 and fewer persons and $31.26 in 2003 dollars for systems serving more than 50,000 

persons. This rate has been inflated to 2013 dollars using the Employment Cost Index. The inflated rate is 

$35.49 for systems serving 50,000 and fewer persons and $42.59 for systems serving more than 50,000 

persons. 

Exhibit A-6-6 Total Burden and Cost to Water Systems

Respondent

Average Unit Burden (hours) Total 

Responses

Total 

Hours

Hourly 

Rate

Total 

Cost Management Technical Clerical Subtotal 

Systems Serving 

More Than 

50,000 Persons

0.70 4.34 1.44 6.48 920 5,962 $42.59 $253,922

Systems Serving 

3,301 – 50,000 

Persons 

0.79 3.49 0.81 5.09 1,939 9,860 $35.49 $349,931

TOTAL 2,859 15,822 $603,853

Note: The average burden per system response is 5.53 hours (15,822/2,859). 

Numbers may not add due to rounding.

A.6.b.ii Cost to States 

Exhibit A-6-7 shows the total burden and costs to states. The cost burden for EPA Regions is discussed in 

section A.6.c. Based on EPA’s projection that all states will participate in the DWINSA, the cost to states

is $1,130,151. The labor costs are based on an average full time equivalent (FTE) cost of $109,990

including overhead, which equates to approximately $52.88 per hour.4 This rate has been inflated to year 

2013 dollars using the Employment Cost Index and is based on the rates provided by the Association of 

State Drinking Water Administrators’ 2011 Survey of State Drinking Water Programs. This survey 

 

4 According to the ICR Handbook, an employee is paid an average of 2,080 hours in one year.
ICR for 2015 DWINSA 33 September 4, 2014

provides the most recent estimate of state salaries and FTEs, which were used in EPA’s 2011 State 

Resource Needs Model.

There are no O&M or capital costs for states under this ICR.

Exhibit A-6-7 Total Burden and Cost to States

Activity

Number of 

States/

Systems

Unit Burden

Total

Burden

(hours)

Hourly 

Rate Total Cost

Up-front

56

5 110 

hours/state 6,160 $52.88 $325,741

2,8596 0.20 

hours/system 572 $52.88 $30,247

State burden for systems serving 

more than 50,000 persons 

assessment

920 5.08

hours/system 4,674 $52.88 $247,161

State burden for systems serving 

3,301 – 50,000 persons assessment 1,939 5.14hours/system 9,966 $52.88 $527,002

TOTAL 21,372 $1,130,151

A.6.c Agency Burden and Cost 

The Agency burden and cost reflects the burden and cost directly incurred by EPA Headquarters and EPA 

Regions and is summarized in Exhibit A-6-8. EPA will also bear the cost of contractor activities as 

detailed in Exhibit A-6-8. Both exhibits distribute burden/costs among Fiscal Years 2014, 2015, 2016 and 

2017, reflecting that Agency and contractor activities will vary substantially over the four-year period.

EPA made the following assumptions in developing its estimate of Agency and contractor burden and 

cost7:

EPA Headquarters

 Over the four-year period, EPA Headquarters will expend a total of 2.8 FTEs (e.g., an average of 

0.7 FTEs per year over the four years). Assuming 2,080 hours per year, this equates to 5,824 

hours.

 The average salary and benefits (i.e., personnel compensation and benefits [PC&B]) of the FTEs 

is at the GS 13, Step 5 level of $163,062. Assuming 2,080 hours per year, this equates to $78.40

per hour.

 

5 Fifty-six includes the 50 states plus the District of Columbia, Puerto Rico, Northern Mariana Islands, American 

Samoa, Guam and the U.S. Virgin Islands. 

6 The total number of systems in the 2015 DWINSA is 2,859 systems. The number of systems shown is the number 

of total systems selected for the 2015 DWINSA.

7 Hourly rates are from U. S. Office of Personnel Management, 2014 General Schedule (GS) Locality Pay Tables

(http://www.opm.gov/policy-data-oversight/pay-leave/salaries-wages/2014/general-schedule/) and overhead rates 

are from Information Collection Request for Public Water Supply Program, December 20, 1993.
ICR for 2015 DWINSA 34 September 4, 2014

EPA Regions 

 Over the four-year period, EPA Regions will expend a total of 1.4 FTEs (i.e., an average of 0.35 

FTE per year) providing support to the 2015 DWINSA. Assuming 2,080 hours per year, this 

equates to 2,911 hours.

 The average salary and benefits (i.e., PC&B) of the 1.4 FTEs is at the GS 11, Step 5 level of 

$113,651. Assuming 2,080 hours per year, this equates to $54.64 per hour.

EPA Contractor(s)

 Over the four-year period, the EPA contractor(s) will expend a total of 27,685 hours of direct 

labor.

 The EPA contractor(s) will provide this professional labor at a total hourly rate, including all 

applicable indirect costs, of $84.46.

Based on these assumptions, EPA estimates that the total burden/cost to EPA (excluding EPA’s 

contractor) for the DWINSA over the four-year period is 8,735 hours and $615,658. Over the three-year 

ICR period, the average annual hours would be 2,912 hours per year and $205,219 per year. Exhibits A-6-

8 and A-6-9, however, provide greater detail on the estimated yearly expenditures for the actual four-year 

effort.

Exhibit A-6-8 Burden/Cost to EPA (Excluding Contractor Activities)

Fiscal 

Year

EPA Headquarters EPA Regions Total

Hours Cost Hours Cost Total 

Hours

Total 

Cost

FY 2014 892 $69,933 446 $24,369 1,338 $94,302

FY 2015 2,020 $158,368 1,009 $55,132 3,029 $213,500

FY 2016 2,020 $158,368 1,010 $55,186 3,030 $213,554

FY 2017 892 $69,933 446 $24,369 1,338 $94,302

TOTAL 5,824 $456,602 2,911 $159,056 8,735 $615,658
ICR for 2015 DWINSA 35 September 4, 2014

Exhibit A-6-9 Burden/Cost of Contractor Activities

Activities

FY 14 FY 15 FY 16 FY 17 Total

Hours Cost Hours Cost Hours Cost Hours Cost Hours Cost

Planning 5,100 $430,746 2,000 $168,920 1,500 $126,690 300 $25,338 8,900 $751,694

Survey Design 200 $16,892 0 $0 0 $0 0 $0 200 $16,892

Peer Review 40 $3,378 0 $0 0 $0 0 $0 40 $3,378

Modeling 0 $0 141 $11,909 997 $84,207 480 $40,541 1,618 $136,656

Database Development 300 $25,338 800 $67,568 300 $25,338 300 $25,338 1,700 $143,582

Survey Production 250 $21,115 473 $39,950 0 $0 0 $0 723 $61,065

Data Analysis 0 $0 7,037 $594,345 1,520 $128,379 0 $0 8,557 $722,724

Report Writing 0 $0 208 $17,568 1,459 $123,227 700 $59,122 2,367 $199,917

Statistical Analysis 0 $0 94 $7,939 656 $55,406 750 $63,345 1,500 $126,690

Tech Assistance 0 $0 480 $40,541 100 $8,446 100 $8,446 680 $57,433

Training 500 $42,230 900 $76,014 0 $0 0 $0 1,400 $118,244

Total 6,390 $539,699 12,133 $1,024,753 6,532 $551,693 2,630 $222,130 27,685 $2,338,275
ICR for 2015 DWINSA 36 September 4, 2014

A.6.d Estimating Respondent Universe and Total Burden and Costs

Respondents for this ICR include CWSs and states. This ICR estimates that the number of CWS 

respondents is 2,859. In addition to the CWS respondents, this ICR assumes 56 states (50 states plus the 

District of Columbia and the U.S. Territories). Therefore, the total number of respondents is 2,915. The 

total costs and burden for these respondents are detailed in Exhibits A-6-10 and A-6-11.

A.6.e Bottom Line Burden Hours and Costs 

Exhibit A-6-10 summarizes the bottom line burden hours and costs for CWSs and states for this 

collection. The total burden is 37,194 hours at a cost of $1,734,004.

Exhibit A-6-10 Bottom Line Respondent Burden 

Respondent Type Burden Hours Total Cost

Water Systems 15,822 $603,853

States 21,372 $1,130,151

TOTAL 37,194 $1,734,004

Over the three-year ICR period, the average annual burden for all respondents (i.e., states and systems 

combined) would be 12,398 hours and the average annual cost would be $578,001 per year. Exhibit A-6-

11 summarizes more specifically the estimated burden hours and costs for CWSs and states for each year 

of the four-year survey period. It is estimated that the states will conduct the up-front activities in 2014

and the data collection activities in 2015. It is estimated that the CWSs will provide information to the 

states for the completion of the data collection instrument in 2015.

Exhibit A-6-11 Burden Hours and Costs for Respondents per Year

Respondent 

Type

Total Hour Burden (per year) Total Cost (per year)

2014 2015 2016 2017 2014 2015 2016 2017

Water 

systems

0 15,822 0 0 $0 $603,853 $0 $0 

States 6,732 14,640 0 0 $355,988 $774,163 0 $0 

TOTAL 6,732 30,462 0 0 $355,988 $1,378,016 0 $0 

Average per 

Respondent 2.31 10.45 0 0 $122 $473 0 $0 

Exhibit A-6-12 summarizes the bottom line burden hours and costs for EPA for this collection. The total 

burden for EPA, including EPA Regions and EPA’s contractor is 36,420 hours at a cost of $2,953,933.
ICR for 2015 DWINSA 37 September 4, 2014

Exhibit A-6-12 Bottom Line Burden Hours and Costs for EPA (including EPA’s 

contractor)

Respondent Type Burden Hours Total Costs

EPA 8,735 $615,658

Contractor 27,685 $2,338,275

TOTAL 36,420 $2,953,933

Exhibit A-6-13 shows the bottom line hour and dollar burden estimate by the Information Collection (IC) 

Entities. IC Entities covered by this ICR include publicly owned CWSs, privately/investor owned CWSs, 

state owned CWSs and state government agencies. 
ICR for 2015 DWINSA 38 September 4, 2014

Exhibit A-6-13 Disaggregated Burden by Affected Information Collection (IC) Entities

Total Number Of 

IC Entities

Burden Per 

Response

Total Hour 

Burden

Hourly 

Rate Total Cost Cost Per Response

Water Systems Respondents 

Serving More 

than 50,000 

Persons

Publicly Owned CWSs 785 

6.48

 5,087 

$42.59

$216,655

$ 276 

Private/Investor Owned CWSs 131 849 $36,159

State Owned CWSs 4 26 $1,107

Tribal Owned CWSs & NPNCWSs - - $0

Subtotal 920 5,962 $253,922

Serving 3,301 

to 50,000 

Persons

Publicly Owned CWSs 1,674 

5.09

 8,512

$35.49

$302,091

Private/Investor Owned CWSs 244 1,241 $44,043 $ 180 

State Owned CWSs 21 107 $3,797

Tribal Owned CWSs & NPNCWSs - - - $- -

Subtotal 1,939 5.09 9,860 $349,931 $ 180

Serving 3,300 

and Fewer 

Persons

Publicly Owned CWSs -

-

-

-

$ -

$ -

Private/Investor Owned CWSs - - $ -

State Owned CWSs - - $ -

Tribal Owned CWSs & NPNCWSs - - $ -

Subtotal - - $ -

Total Water System Respondents

Publicly Owned CWSs 2,459 5.53 13,599 $518,746 $ 211 

Private/Investor Owned CWSs 375 5.57 2,090 $80,202 $ 214 

State Owned CWSs 25 5.32 133 $4,904 $ 196 

Tribal Owned CWSs & NPNCWSs - - - $- -

Subtotal 2,859 5.53 15,822 $603,853 $ 211 

Total State Government Respondents 56 381.64 21,372 $ 52.88 $ 1,130,151 $ 20,181 
ICR for 2015 DWINSA 39 September 4, 2014

Total Number Of 

IC Entities

Burden Per 

Response

Total Hour 

Burden

Hourly 

Rate Total Cost Cost Per Response

Total Tribal Authority Respondents - - - $ - $ - $ -

Total Respondents 2,915 12.76 37,194 $ 1,734,004 $ 595

Note: Numbers may not add due to rounding. 
ICR for 2015 DWINSA 40 September 4, 2014

A.6.f Reasons for Change in Burden 

This ICR does not modify an existing ICR. However, it should be noted that an ICR was prepared for the 

previous survey effort done in 2011, which is outside of the three-year window for modifying an existing 

ICR for a new effort. For purposes of this reinstatement, the EPA has provided a comparison of burden of 

the proposed new effort to the estimates of the previous 2011 effort’s ICR.

The estimated total public reporting burden over the entire four-year length of the 2011 DWINSA was 

48,995 hours; the total burden for the 2015 Survey is estimated to be 37,194 hours. The 2011 DWINS 

average burden per respondent was estimated to be 15.24 hours whereas for 2015 the average is estimated 

to be 12.76 hours per respondent. The reduction in burden for the 2015 DWINSA is attributed to: 

1. The use of a modified data collection approach, whereby a majority of systems from the 2011

DWINSA are being resurveyed and a smaller pool of systems will be randomly surveyed.

2. For the 2015 DWINSA, existing data from the 2011 DWINSA for Tribal systems will be 

extrapolated to 2015 needs using construction cost inflation calculations and taking into account 

any shifts in the number and size of these systems. 

A.6.g Burden Statement 

The public reporting burden for collections included in this ICR is detailed above. The total public 

reporting burden over the four-year length of the 2011 DWINSA is estimated to be 37,194 hours, of 

which 15,822 hours are attributable to water systems. These estimates include time for gathering and 

submitting of information. Public reporting burden (i.e., combined state and system burden) for this 

collection of information is estimated to average 12.76 hours per response.8 Respondent burden for the 

water system alone is 5.53 hours per system response.

9

Burden means the total time, effort or financial resources expended by people to generate, maintain, 

retain, disclose or provide information to or for a federal agency. This includes the time needed to review 

instructions, adjust the existing ways to comply with any previously applicable instructions and 

requirements, train personnel to respond to the information collection request, search data sources, 

complete and review the collection of information and transmit or otherwise disclose the information. An 

agency may not conduct or sponsor, and a person is not required to respond to, a request for information 

collection unless it displays a currently valid OMB control number. The OMB control numbers for EPA’s 

regulations are listed in 40 CFR Part 9 and 48 CFR Chapter 15.

Please send comments on the Agency’s need for this information, accuracy of the burden estimates and 

any suggested methods for minimizing respondent burden to: Director, Office of Environmental 

Information, Collection Strategies Division, U.S. Environmental Protection Agency (2822T), Ariel Rios 

Building, 1200 Pennsylvania Ave., N.W., Washington, D.C. 20460; and to the Office of Information and 

Regulatory Affairs, Office of Management and Budget, 725 17th Street, NW, Washington, DC 20503, 

Attention: Desk Officer for EPA. Please include the EPA ICR number and OMB control number in any 

correspondence.

 

8 For this ICR, the number of responses is calculated at 2,915 (920 systems serving more than 50,000 people, 1,939 

systems serving 3,301 to 50,000 people and 56 states). The burden per response is calculated as the total respondent 

burden (37,194) divided by the number of responses (2,915).

9 See Exhibit A-6-6.
ICR for 2015 DWINSA 41 September 4, 2014

PART B OF THE SUPPORTING STATEMENT (FOR STATISTICAL 

SURVEYS)

INTRODUCTION TO PART B

The Environmental Protection Agency (EPA) will conduct the following type of statistical 

survey for the 2015 State Drinking Water Infrastructure Needs Survey and Assessment 

(DWINSA). EPA will undertake an assessment of community water systems (CWSs) serving 

populations of more than 3,300. EPA will use the same methodology for collecting data for 

CWSs serving more than 3,300 persons as was used in the 2011 DWINSA with the 

implementation of a modified panel approach. EPA will not be collecting new data from the 

field for CWSs serving 3,300 and fewer or from American Indian systems, Alaska Native 

Village water systems or not-for-profit noncommunity water systems; instead, the Agency will 

update the data from previous surveys based on construction cost inflation and on shifts in the 

number and sizes of these water systems.
ICR for 2015 DWINSA 42 September 4, 2014

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ICR for 2015 DWINSA 43 September 4, 2014

2015 DWINSA

B.1 SURVEY OBJECTIVES, KEY VARIABLES AND OTHER PRELIMINARIES

B.1.a Survey Objectives 

The primary objective of the 2015 DWINSA is to collect information from water systems on the 

infrastructure they need to continue to provide safe drinking water to consumers. These data are used to 

produce a national estimate as well as state-specific estimates of water systems’ 20-year need. EPA has 

established policies to ensure that the overarching goals of the survey are met:

 Estimate the total national 20-year need

 Estimate the total 20-year need for each fully participating state

 Provide complete and accurate data to Congress

 Provide a tool to fairly distribute DWSRF capitalization funds to states

 Maintain the credibility of the DWINSA findings

EPA proposes to collect information on the cost of water systems’ infrastructure needs. If cost data are 

not available from systems, EPA proposes to collect information that will enable the Agency to model 

costs. In the data collection instrument, the respondent will identify needs on a project-by-project basis 

and list the “type(s) of need” that the project will meet. The “types of need” include raw water source, 

transmission, source water treatment, storage, distribution, pumping stations and other needs.

EPA will use the information from the DWINSA to estimate capital investment requirements of drinking 

water systems. The information will be used to allot DWSRF monies among states and as part of an 

allotment formula for the DWSRF Tribal Set-Aside (TSA) Program. 

For the 2015 DWINSA, EPA is proposing to use a modified panel approach to select survey respondents. 

The modified panel approach will involve dropping a random selection of 25 percent of the systems 

serving 3,301 to 100,000 people that participated in the 2011 DWINSA and then drawing a random 

sample to replace those systems in the survey for the 2015 DWINSA. This will be done for each state and 

by strata. By primarily using information from the 2011 DWINSA, this approach would reduce the 

amount of time required to prepare and review the responses from systems resurveyed in 2015. 

For the new systems selected for the 2015 Assessment, EPA will use the same methodology as used in 

previous DWINSAs. The sampling design is discussed in detail below.

B.1.b Key Variables 

Several key variables are available from the Safe Drinking Water Information System (SDWIS). To 

ensure accuracy, the 2015 DWINSA will verify these data by asking respondents to confirm existing 

information (pre-populated on the data collection instrument) or correct it. These variables include 

population served, total design capacity, number of service connections, primary source of supply, 

ownership type (private or public) and whether the system purchases water from or sells water to another 

water system. 

Information on capital needs will be collected from respondents on a project-by-project basis. For each 

project, respondents will be asked to provide the following types of information: type of need; reason for 

need; documentation of need and cost (if necessary); if the project is a new project or to replace, 

rehabilitate or expand existing infrastructure; if the project is needed now to protect public health or if it is 

needed over the next 20 years to continue to provide safe drinking water; the federal regulation or state 

requirement (if the project is to meet a current regulation or state requirement); design capacity of source, 
ICR for 2015 DWINSA 44 September 4, 2014

storage and treatment projects; length and diameter of pipe projects; diameter for projects such as water 

meters; cost of the project (if available); and date of the cost estimate. For most of these variables, 

respondents will choose the appropriate “documentation,” “type of need,” “reason for need” or 

“regulation or requirement” from EPA’s Lists of Codes. 

The principal variable of interest is total projected capital needed for each water system in the 2015

DWINSA for the time period of January 1, 2015, through December 31, 2034. The total capital need for 

all systems in each state (to be derived from the statistical sample of systems) is the key variable that 

decision-makers at EPA use to allocate funds to states based on need.

The method of data collection has been designed to minimize burden on respondents while ensuring that 

information is collected in a consistent manner. Collecting information on a project-by-project basis, for 

example, will be particularly helpful in reducing burden since most respondents develop Capital 

Improvement Plans (CIPs) on a project-by-project basis. 

Information on type of need will be used to disaggregate total capital needs for EPA’s Report to 

Congress. Information on the reason for need will be used to verify the public health benefit of the need. 

Information on the date of the cost estimate will be used to provide a consistent basis for cost estimates 

across systems. Information on a regulation or requirement will be used to determine the reported project 

costs related to federal regulations or state requirements.

If a system cannot provide cost estimates, additional data are necessary so that the Agency can impute 

costs. Each of these variables is described in greater detail later in this document.

B.1.c Statistical Approach 

The 2015 DWINSA is being designed to achieve a desired level of precision for state-level estimates of 

total capital needs for systems serving more than 3,300 persons. EPA proposes a modified panel approach 

that includes a census of large systems and a survey of a statistical sample of medium-sized systems to 

estimate total capital needs. This statistical approach minimizes burden while achieving the desired level 

of precision. 

The 2015 DWINSA design divides CWSs serving populations of more than 3,300 into two groups: CWSs 

serving populations of more than 100,000 and systems serving populations of 3,301 to 100,000. EPA 

proposes to sample with certainty systems serving more than 100,000 persons. These systems have the 

largest capital needs and they have the staff to respond efficiently to the 2015 DWINSA. EPA proposes to 

use a random sample of systems serving 3,301 to 100,000 persons. This methodology can reduce burden 

and still achieve the DWINSA data quality objectives. 

To further reduce burden, EPA proposes using a modified panel approach for the 2015 DWINSA. Rather 

than select a completely new sample of systems in 2015, EPA will reassess the needs of most of the 

systems that participated in the 2011 Assessment. EPA will replace 25 percent of the sample of systems 

serving 3,301 to 100,000 people. By state and stratum, EPA will randomly select 25 percent of the sample 

to drop and will then randomly select replacement systems from the sampling frame. By primarily using 

information from the 2011 DWINSA, this approach would reduce the amount of time required for 

systems to prepare and states to review the responses from systems resurveyed in 2015. This approach 

will maintain EPA’s sampling targets for each stratum and ensure that EPA continues to meet its 

precision targets for each state. Additionally, by using information from the 2011 review, the modified 

panel approach would reduce the amount of time required for EPA’s contractor to review each system’s 

response. By replacing 25 percent of the sample, EPA will reduce a potential source of bias introduced by 

the panel. (When a completely new sample was selected for each assessment, the sampling error was a 

random component that changed from survey to survey. With the panel approach, this error becomes 
ICR for 2015 DWINSA 45 September 4, 2014

systematic.) By refreshing 25 percent of the sample, the approach alleviates this potential source of bias 

and helps to ensure that the 2015 sample represents the need as it exists in 2015.

To meet the state-level precision targets, EPA will use the same strata as in the 2011 DWINSA. As 

previously mentioned, EPA will adjust the sample size to accommodate changes in the sample frame. 

These changes may address new systems, systems that are no longer active and systems that have 

“migrated” between strata (become smaller or larger, or changed source). If EPA determines that there 

have been substantial changes in the size of the sample frame since the 2011 DWINSA, EPA will adjust 

the sample size as needed to ensure that the precision targets are met for each state. As in the 2011 

DWINSA, EPA will first determine the total sample size for each state to meet the target level of 

precision. EPA will then allocate the sample to strata in order to maximize the efficiency of the design. 

EPA is designing and conducting the 2015 DWINSA with the assistance of a contractor:

Contractor

The Cadmus Group, Inc.

100 5th Avenue, Suite 100

Waltham, MA 02451

(617) 673-7000

Contractor Roles

- Oversight of data collection instrument design

- Oversight of statistical sample design

- Training

- Data collection instrument package 

distribution: logistics

- Technical support for respondents and states

- Review of all survey responses for 

conformance to survey policies and project 

allowablity criteria

- Model development

- Data processing

- Statistical sample design

B.1.d Feasibility 

The 2015 DWINSA data collection instrument has been designed with the capabilities of the typical 

respondent in mind. To fully assess feasibility, the Agency undertook the following steps. EPA convened 

a workgroup (see Section A.5.b) to comment on the proposed data collection and its feasibility. The data 

collection instrument to be used for the 2015 DWINSA is generally the same form as used for the past 

two DWINSAs. For the 2007 DWINSA, EPA conducted a pre-test in which EPA’s contractor met with 

individual CWS operators and discussed the proposed survey. System operators were asked to comment 

on all proposed data elements and the feasibility of collecting information by a mail survey. The Agency 

recognizes that most systems serving fewer than 50,000 persons and some that serve 50,000 or more may 

not have cost data or documentation of costs for some projects. In those cases, the 2015 DWINSA data 

collection instrument requests other readily available information that EPA can use to model costs. EPA 

will emphasis to respondents that they are not expected to develop cost estimates for the purposes of the 

2015 DWINSA. In addition, EPA (or states) will provide systems with technical assistance for

completing the data collection instrument.

EPA has developed cost models for most of the infrastructure needs included in the 2015 DWINSA based 

on the size and capacity of a project. These cost models were originally developed during the 1995

DWINSA, have been updated during subsequent assessments, including the 2011 DWINSA, and will be 

used again for the 2015 DWINSA. New cost models may be developed for weaker cost models, 

influential cost models and new technology.
ICR for 2015 DWINSA 46 September 4, 2014

The time frame for the 2015 DWINSA is acceptable to the users of data within the Office of Ground 

Water and Drinking Water (OGWDW) and sufficient to complete a report to Congress by its anticipated 

due date of early 2017. The schedule also is acceptable to other users of the data. 

B.2 SURVEY DESIGN

This section contains a detailed description of the statistical survey design and modified panel approach 

including a description of the sampling frame, sample identification, precision requirements and data 

collection instrument.

The sample design for the 2015 DWINSA is stratified random sampling within each state. In cases where 

the state is not participating in the data collection for systems serving 3,301 to 100,000 persons, EPA will 

not provide state-specific results, as the data collection for these states does not meet the DWINSA data 

quality objectives. EPA will include an overall national result for the systems serving 3,301 to 100,000 

persons, using the average need by strata of the systems in states that are participating in the full 2015 

DWINSA. For states that are fully participating in data collection for systems serving 3,301-100,000 

persons, the 2015 DWINSA will use a modified panel approach for sampling these systems within each 

state. This approach is described in more detail in Section B.2.b.

Stratification increases the precision of estimates compared with a simple random sample of the target 

population of systems. In stratified samples, the target population is divided into non-overlapping groups, 

known as strata, from which separate samples are drawn. The goal of stratified sampling is to choose 

sample sizes within each stratum in a manner designed to obtain maximum precision in the overall 

estimate for the population. Stratification variables for this study include: population size (populations of:

3,301 to 10,000; 10,001 to 25,000; 25,001 to 50,000; 50,001 to 100,000 and more than 100,000) and 

primary sources of supply (surface and ground). Systems serving more than 100,000 persons are selected 

with certainty. For the 2011 DWINSA, the size of each state’s sample of systems serving populations of 

3,301 to 100,000 was set to meet the 2011 DWINSA’s data quality objectives. For the 2015 DWINSA, 

the survey will rely on a modified panel approach in which 75 percent of the 2011 DWINSA respondents 

serving populations of 3,301 to 100,000 are resampled, and 25 percent are put back into the frame and a 

new 25 percent are drawn.

EPA’s precision target for the 2015 DWINSA is to be 95 percent confident that the true need for each 

state lies within an interval of plus or minus 10 percent of the estimated need. These precision targets are 

identical to the targets for the 2011 Assessment. The 2011 sample, modified as described above, will meet 

the assessment’s precision target. The sample sizes will be adjusted to account for changes in the 

inventory of systems, if necessary, to ensure the 2015 sample meets the precision targets. 

B.2.a Target Population and Coverage 

The target population for the 2015 DWINSA is the number of CWSs in the nation. A CWS is a public 

water system (PWS) that serves at least 15 service connections used by year-round residents or regularly 

serves at least 25 year-round residents (40 CFR 141.2). The 2015 DWINSA is designed to produce 

estimates of the capital need of systems serving more than 3,300 persons for each participating state. In 

partially surveyed states, EPA will be able to provide state-specific results for systems serving 100,000 or 

more persons. EPA will include an overall national result for the systems serving 3,301 to 100,000 

persons using the average need by strata of the systems in participating states and the total number of 

systems by strata in the partially surveyed state. The 2015 DWINSA is designed to produce estimates of 

the capital need of systems serving 3,300 and fewer persons by state and for the nation as a whole using 

the results of the 2007 DWINSA. 
ICR for 2015 DWINSA 47 September 4, 2014

B.2.b Sample Design 

This section describes the sample design. It includes a description of the sampling frame, target sample 

size, stratification variables and sampling method. The sampling design employed is a stratified random 

sample of CWSs. The strata employed in the design are discussed in Section B.2.b.iii. Neyman allocation 

is used to efficiently allocate the sample of water systems among the strata.

B.2.b.i Sampling Frame 

The sampling frame is developed from SDWIS. SDWIS is a centralized database for information on 

PWSs, including their compliance with monitoring requirements, maximum contaminant levels (MCLs) 

and other requirements of the SDWA. The following information will be extracted from SDWIS for the 

statistical survey and verified by participating states:

 Name of system.

 Contact person.

 Address of system.

 Population served.

 Total design capacity.

 Number of connections.

 Primary source (surface water or ground water).

 PWS identification number (PWSID).

 Ownership type.

 Whether the water system purchases/sells water from/to another water system.

From these data, EPA will develop the frame from which EPA will calculate summary statistics (e.g., 

number of systems per state in pre-defined strata) for use in calculating sample size. For the modified 

panel approach, the 2015 sampling design will use the 2011 DWINSA sample and make targeted 

modifications to account for changes in the inventory of systems between 2011 and 2015. Systems that 

have closed since the 2011 DWINSA will be removed from the 2015 survey. The needs of merged 

systems will remain in the survey as the need of the combined system. New systems added to the 

inventory (i.e., systems that served 3,300 or fewer people in 2011 that now serve more than 3,300 people, 

or newly created systems) will be sampled to ensure the sample is representative of systems in 2015. New 

large systems (those serving more than 100,000 persons) will also be added to the census.

Justification for the Use of SDWIS

The following criteria are often used in assessing a proposed sampling frame:

 It fully covers the target population.

 It contains no duplication.

 It contains no foreign elements (i.e., elements that are not members of the population).

 It contains information for identifying and contacting the units selected in the sample.

 It contains other information that will improve the efficiency of the sample design.

The units of observation for this survey are CWSs, a subset of PWSs. SDWIS is the ideal choice for a 

sample frame because of its inclusive coverage of all units of observation for the 2015 DWINSA. In 

addition, SDWIS has two other advantages: it contains information that will facilitate contacting the 

respondents and it contains other information that is useful in stratifying the sample, thereby improving 

the efficiency of the sample design.
ICR for 2015 DWINSA 48 September 4, 2014

In previous surveys where SDWIS was used as a sample frame, there have been criticisms of its utility. 

Since 1989, EPA has conducted audits of the quality of SDWIS data. As a result, EPA is aware of the 

problems with SDWIS. The audits, however, show that errors in classification of systems by strata 

proposed for the 2015 DWINSA are rare. The audits show that systems are misclassified by population or 

source in less than one percent of all cases. 

To mitigate any potential problems with the sample frame, the 2015 DWINSA design anticipates 

substantial state involvement in the 2015 DWINSA process. For example, states will be checking the 

sample frame of systems that will be used to determine the final sample. In EPA’s experience, states often 

have in-house data systems with very accurate data. Even if these data are not transmitted to SDWIS, they 

are available and can be used by states to check the sample frame. 

B.2.b.ii Sample Size 

Exhibit B-2-1 at the end of this subsection shows the preliminary sample sizes for the 2015 DWINSA. 

For the modified panel approach, sample sizes for the 2015 DWINSA will be the same as for the 2011 

DWINSA except for changes to accommodate: (1) the addition of large systems serving more than 

100,000 people since the 2011 survey; (2) any partially surveyed states from the 2011 survey that fully 

participate in the 2015 survey; and (3) changes in the inventory of medium systems, including systems 

changing size or source categories or the creation of new systems. As shown on Exhibit B-2-1, the 

sampling design will be implemented to achieve state-level precision targets for CWSs serving more than 

3,300 persons. Precision targets are discussed in Section B.2.c. 

The task of determining the sample size for each stratum requires two steps. The first step determines the 

sample size for each state that achieves the precision targets for that state. The second step allocates the 

sample among the relevant strata in the state. The strata are described in section B.2.b.iii. 

The first step calculates the total number of systems required at the state level to meet the precision 

requirements. The sample size is given by:

g

H

h

gh gh

g

V

N s

n

2

1

0

















Where: n0g = the sample size for state g (prior to the finite population correction)

Ngh = the total number of systems in the gth state in the hth stratum (taken from SDWIS)

sgh = the standard deviation of the variable of interest in the gth state for the hth stratum 

(estimated using data from the data from previous assessments) 

H = the number of strata defined in the sample design for the gth state 

Vg = the desired sampling variance for the total system (those serving more than 3,300 

persons) capital needs estimate for state g.

The desired error in the sample is expressed as a relative error. In the above equation, Vg = (d/Zα * 

Yg

ˆ

)

2

. 

Yg

ˆ

is an estimate of the total capital needs for a given state. 

Yg

ˆ

is computed for each state by calculating 

the mean total capital needs for stratum h (from the prior DWINSAs) and multiplying this mean by the 

actual number of systems in each stratum for that state (Ngh). Summing across strata provides an estimate 
ICR for 2015 DWINSA 49 September 4, 2014

of 

Yg

ˆ

. d is the half-width of the desired confidence interval (0.10 for the Assessment). Zα is the value of a 

standard normal distribution for a confidence level of 1- α, (1.96 for the Assessment). 

Because the number of water systems is known and finite, the following population correction is applied:





 H

h

gh gh

g

g

g

N s

V

n

n

1

2

0

1

1

The second step allocates the total sample to each sampling stratum. EPA will randomly draw this 

number of samples from each of these strata. The Neyman allocation is used to determine the sample size 

for each stratum:

10





























H

h

gh gh

gh gh

gh g

N s

N s

n n

1

(Because systems serving populations more than 100,000 are to be sampled with certainty, H is the 

number of strata of systems serving 100,000 or fewer persons.)

In order to implement these sample size and sample allocation equations, EPA needs estimates for Vg, 

Ngh, sgh and mean total capital needs by stratum. Information on mean total capital needs by stratum and 

sgh were estimated using data from the prior DWINSAs.

Exhibit B-2-1 State Sample Sizes

State

Estimated Total Number Of 

Systems Serving More Than 

3,300 Persons 

Estimated Sample Size 

For Systems Serving 

More Than 3,300 Persons

Alaska * 17 1

Alabama 348 131

Arkansas 181 83

American Samoa 1 1

Arizona 130 39

California 688 170

Colorado 169 61

Connecticut 57 36

District of Columbia 1 1

 

10 J. Neyman, “On the Two Different Aspects of the Representative Method: The Method of Stratified Sampling and 

the Method of Purposive Selection,” Journal of the Royal Statistical Society, Vol. 97 (1934), pp. 558-606; as cited in 

William G. Cochran, Sampling Techniques (New York: John Wiley & Sons), 1977. 
ICR for 2015 DWINSA 50 September 4, 2014

State

Estimated Total Number Of 

Systems Serving More Than 

3,300 Persons 

Estimated Sample Size 

For Systems Serving 

More Than 3,300 Persons

Delaware * 30 3

Florida 387 128

Georgia 237 66

Guam 3 3

Hawaii * 30 2

Iowa 138 53

Idaho * 51 1

Illinois 460 98

Indiana 214 82

Kansas 117 65

Kentucky 259 141

Louisiana 231 65

Massachusetts 253 73

Maryland 59 26

Maine 35 25

Michigan 303 63

Minnesota 181 91

Missouri 216 121

Northern Mariana Islands 2 2

Mississippi 202 105

Montana * 35 1

North Carolina 280 80

North Dakota * 32 0

Nebraska * 43 2

New Hampshire * 39 1

New Jersey 242 61

New Mexico * 60 1

Nevada 35 15

New York 362 50

Ohio 320 90

Oklahoma 165 86
ICR for 2015 DWINSA 51 September 4, 2014

State

Estimated Total Number Of 

Systems Serving More Than 

3,300 Persons 

Estimated Sample Size 

For Systems Serving 

More Than 3,300 Persons

Oregon 116 54

Pennsylvania 349 83

Puerto Rico 118 58

Rhode Island * 28 3

South Carolina * 159 9

South Dakota * 45 2

Tennessee 288 158

Texas 987 144

Utah 109 50

Virginia 160 56

Virgin Islands 2 2

Vermont * 34 0

Washington 213 58

Wisconsin 181 58

West Virginia * 110 1

Wyoming * 27 0

Total 9,539 2,859

*Fifteen states are expected to opt out of participating in the statistical portion of the survey (i.e., collecting data from systems 

serving 3,301 to 100,000 persons). However, those states that have systems that serve more than 100,000 people will participate 

in the census portion of the survey (i.e., collecting data from systems serving more than 100,000 persons). For those 15 states, the 

number in the “Estimated Sample Size for Systems Serving More Than 3,300 Persons” represents the total number of systems in 

the state that serve more than 100,000 persons.

B.2.b.iii Stratification Variables 

The objective of stratification is to increase the efficiency of the sampling design (thereby reducing the 

number of systems to be sampled for a given level of precision). Stratified sampling may produce a gain 

in precision in the estimates of the characteristics of the target population as compared to simple random 

sampling. In stratified sampling, the target population (i.e., CWSs) is divided into non-overlapping strata 

that are internally homogeneous, in that the measurements vary little from one unit to another (i.e., the 

within-stratum variance is minimized). If the within-stratum variance is relatively small, then a precise 

estimate of the variable of interest can be obtained with relatively small samples. Each of the strata 

estimates can be combined to obtain a precise estimate for the overall target population. 

EPA’s drinking water programs have historically evaluated CWSs based on (1) the number of persons 

served and (2) the primary water source (ground water and surface water).11 Using total capital need 

 

11 For the purposes of the 2015 DWINSA, purchased surface water systems are included with ground water systems.

This design yields lower within-stratum variance and has been used since the 1999 DWINSA.
ICR for 2015 DWINSA 52 September 4, 2014

information obtained from prior DWINSAs, EPA evaluated several classification schemes. This analysis 

showed that the stratification scheme used in prior assessments (10 strata based on size and source) would 

be appropriate for the 2015 DWINSA. For some states, EPA may combine the 10,001to 25,000 and 

25,001 to 50,000 size categories within each source category, resulting in 8 rather than 10 strata. EPA will 

combine these two size categories only if the sample using 8 strata is more efficient than the sample using 

10 strata. The proposed strata for systems serving more than 3,300 persons are as follows: 

Size of Population Served Source Sample Methodologies

3,301 – 10,000 Ground Panel approach with 25 percent refresh using a random 

sample. 3,301 – 10,000 Surface

10,001 – 25,000 Ground Panel approach with 25 percent refresh using a random 

sample. In some states the number of strata will be reduced 

based on analysis of optimal stratum boundaries. Specifically, 

in some states systems serving between 10,001 and 50,000 

will be in one size group rather than two. 

10,001 – 25,000 Surface

25,001 – 50,000 Ground

25,001 – 50,000 Surface

50,001 – 100,000 Ground Panel approach with 25 percent refresh using a random 

sample 50,001 – 100,000 Surface

More than 100,000 Ground Sampled with certainty

More than 100,000 Surface

B.2.b.iv Sampling Method 

As indicated above, all CWSs serving populations of more than 100,000 will be sampled with certainty. 

For systems serving 3,301 to 100,000 persons, all CWSs will be allocated to eight strata, based on the 

population served and primary water source. The sample size for each stratum in each state will be 

determined by the sampling strategy outlined above. As previously described, the modified panel

approach that will be used for the 2015 sample will begin with the 2011 DWINSA sample and make 

targeted modifications to account for changes in the sample between 2011 and 2015. EPA will then 

“refresh” the sample by randomly replacing 25 percent of the 2011 sample of systems serving 3,301 to 

100,000 people with systems that were not included in the 2011 Assessment. To refresh the sample, 25 

percent of systems serving 3,301 to 100,000 persons will be dropped from the survey and returned to the 

pool of systems that were not selected in 2011. The “refresh” will then randomly select systems from 

among the pool of systems that were not in the 2011 sample, the systems that were randomly dropped and 

new systems so that the number of systems in the sample reaches the same size as the 2011 sample.

The sampling method for the 25 percent refresh will be similar to the approach used in the 2011 survey. 

An equal probability random sample will be drawn from each stratum. Anticipating a level of nonresponse, EPA will over-sample the refresh systems to achieve the desired number of completed data 

collection instruments. Since the expected response rate for systems serving 3,301 to 100,000 persons is 

approximately 90 percent, EPA has increased the sample by approximately 10 percent. However, as 

discussed below, the DWINSA has consistently achieved a higher response rate than estimated. Therefore 

EPA has included the full sample size estimate in the burden estimate of this ICR.
ICR for 2015 DWINSA 53 September 4, 2014

B.2.c Precision Requirements 

B.2.c.i Precision Targets 

The sampling design for the 2015 DWINSA will be implemented at the state level. EPA’s goal is to be 95 

percent confident that the margin of error, when estimating the total capital needs facing these systems in 

each state, will be plus or minus 10 percent of the total need for these systems. For example, if the total 

need for these systems in a state is estimated to be $2 billion, EPA will be 95 percent confident that the 

actual total need is between $1.8 billion and $2.2 billion.

B.2.c.ii Nonsampling Error 

EPA has developed an assessment approach that will employ several quality assurance techniques to 

maximize response rates, response accuracy and processing accuracy to minimize non-sampling error. 

Particular emphasis will be placed on maximizing response rates. Standard methods that have proved 

effective in other surveys involving states and water systems will be used, including the following:

 EPA and the states will coordinate in the production of a cover letter for the 2015 DWINSA. 

EPA’s opinion (shared by state drinking water administrators and trade associations) is that 

surveys on state letterhead will be better received than surveys on EPA letterhead. Therefore, 

states can use state-level cover letters signed by a senior state official instead of the EPA letter.

 The states will place a telephone call to each participating system to ensure that they understand 

the survey process and their role. 

 The data collection instrument design, content and format were reviewed by states that 

participated in the 1995, 1999, 2003, 2007 and 2011 DWINSAs. 

 Questions being asked are those that owners or operators of systems should know. EPA does not 

ask questions that require monitoring, research or calculations on the part of the respondent.

 The data collection instrument design is limited to a cover page of system information and 

characteristics and one project table, with three optional tables to record general information 

about the system’s infrastructure inventory. By limiting the information requested, EPA believes

that the average water system respondent can complete the data collection instrument in 

approximately 5.53 hours. Exhibit A-6-6 shows the breakdown of the total burden hours for 

CWSs by system size in the 2015 DWINSA.

 Respondents will be encouraged to call state personnel who will be trained to answer questions. 

In addition, EPA will provide technical assistance to states and water systems.

 The electronic format of the survey will make returning the data collection instrument convenient.

Standard methods to reduce other sources of non-sampling error also will be used:

 EPA expects complete coverage of the target population using SDWIS, supplemented by state 

review of all systems.

 Data will be 100 percent independently keyed and verified.

 The data collection instrument is pre-coded to improve accuracy by eliminating unnecessary 

processing steps. 
ICR for 2015 DWINSA 54 September 4, 2014

Supplementing these standard methods, EPA proposes several unique steps to eliminate non-sampling 

error which have been developed in concert with organizations representing the states and water systems. 

These organizations believe that the 2015 DWINSA is important and that a high level of participation by 

all water systems is essential to its success. Because of the substantial commitment being made by states 

and water systems to the 2015 DWINSA, EPA believes that response rates will be higher than most 

surveys of similar respondents. To ensure success, states and organizations representing water systems are 

taking the following steps. 

 Participation of the states. Because the 2015 DWINSA will be used to allocate DWSRF funds to 

states, each entity has a strong interest in achieving a high response rate. EPA believes that their 

participation will be a key factor in guaranteeing high response rates and low item non-response. 

Personnel who work with water systems every day are in a strong position to encourage systems 

to complete the 2015 DWINSA form. States have committed to assisting EPA in achieving a high 

response rate by participating in follow-up activities. EPA will provide technical assistance to any 

system that has questions about the 2015 DWINSA. 

 Participation of Organizations Representing Water Systems. EPA anticipates public support of 

organizations representing water systems. The prior assessments were supported by groups such 

as the American Water Works Association (AWWA), the National Association of Water 

Companies (NAWC) and the Association of Metropolitan Water Agencies (AMWA). 

This support by the organizations representing the respondents for the 2015 DWINSA can be 

helpful in many ways to minimize non-sampling errors. For example,

– In past DWINSAs, national water associations sent letters to each system in their 

membership, stressing the importance of surveying drinking water infrastructure needs. 

These letters, along with the letter from the states, helped convince water systems to 

respond. EPA will seek similar support from these associations for the 2015 DWINSA

effort to encourage systems to complete the data collection instrument.

– In the past DWINSAs, the largest association representing water systems serving 

populations greater than 3,300, AWWA, provided support through its national 

organization. To improve the response rate, AWWA enlisted the support of its state 

affiliates to conduct telephone follow-up calls to encourage response. AWWA assisted in 

past DWINSAs to help achieve high response rates. EPA will seek similar support from 

AWWA in support of the 2015 DWINSA. 

 Communications Strategy. EPA has developed a comprehensive communications strategy that 

will inform likely respondents of the need for their participation. This strategy includes articles in 

magazines, newsletters and bulletins of all major organizations that represent (or communicate 

with) water systems. This includes publications of all of the organizations mentioned above, plus 

the state and local affiliates of these organizations. The strategy is designed to develop 

widespread peer-group support for participation in the 2015 DWINSA.
ICR for 2015 DWINSA 55 September 4, 2014

B.2.d Data Collection Instrument Design 

Questions about system characteristics (name, population served, number of connections and other 

customary business information) will be pre-populated on all data collection instruments. The respondent 

needs only to enter accurate information if any pre-populated information is not correct.

The 2015 DWINSA is based on a matrix project table that requests a list of capital water system 

infrastructure projects that the system plans for the period 2015 through 2034. For each project listed, the 

water system is asked to provide: 

 Type of need. 

 Reason for need. 

 Documentation of need. 

 If the project is for new infrastructure or to replace, rehabilitate or expand existing infrastructure. 

 If the project is needed now to protect public health or if it is needed over the next 20 years to 

continue to provide safe drinking water. 

 The federal regulation or state requirement if the project is needed to meet a current federal 

regulation or state requirement. 

 Design capacity of source, storage and treatment projects. 

 Length and diameter of pipe projects. 

 Diameter for projects such as meters. 

 Cost of the project (if available). 

 Date of the cost estimate (if necessary). 

 Documentation of cost (if necessary). 

For most of these variables, respondents will choose the appropriate “documentation,” “type of need,”

“reason for need,” or “regulation or requirement” from EPA’s “Lists of Codes” (Appendix B). The data 

collection instrument has been designed to be concise, to avoid jargon and to avoid ambiguous words or 

instructions. Terms and formats have been standardized to the extent possible. There is no intentional bias 

in the ordering of the items. 

B.3 PRE-TESTS AND PILOT TEST

B.3.a Pre-tests 

For the 2007 DWINSA the data collection instrument and some policies were modified substantially. 

EPA conducted two pre-tests of the data collection instrument for the 2007 DWINSA. These pre-tests 

were conducted by EPA’s contractor, The Cadmus Group, Inc. The pre-tests gathered feedback on the 

effectiveness of the data collection instrument; highlighted imprecise, ambiguous or redundant questions;

and indicated where further inquiry was needed. A pre-test was held in both Maine (four participants) and 

Montana (three participants). These states were chosen because they were both partially surveyed states 

and therefore most of their systems did not participate in the 2007 DWINSA. Also, the contractor 
ICR for 2015 DWINSA 56 September 4, 2014

conducting the pre-tests has offices in both these states and by conducting the pre-test in these states was

able to reduce costs. The names of the seven systems were provided to EPA by the 2007 DWINSA state 

contacts. Based on the comments received, EPA made modifications to the data collection instrument. 

Since EPA’s pre-tests of the 2007 DWINSA data collection instrument were so extensive, and because 

few changes have been made to the data collection instrument since the 2007 DWINSA, EPA believes 

that a pre-test is not needed for the 2015 DWINSA.

The data collection instrument was further modified for the 2011 DWINSA by the addition of questions 

and codes to gather information on projects with “green” and climate readiness attributes. Consequently, 

EPA conducted a limited peer review focused on these new questions. EPA did not conduct a pre-test of 

the 2011 DWINSA data collection instrument. Based on the limited number of states that submitted 

projects with “green” or climate readiness attributes indicated in the 2011 effort, EPA concluded these 

attributes were likely underreported. For the 2015 DWINSA, the “green” and climate readiness 

questions will be removed from the data collection instrument. Instead, EPA will explore streamlined 

approaches that might enable the Agency, during the Survey review process, to identify and flag projects 

that are likely to have “green,” climate readiness or climate resilience attributes. 

B.3.b Pilot Test 

To eliminate unnecessary burden on states and water systems, it has been decided that no pilot test for the 

2015 DWINSA will be conducted. A pilot test was conducted for the 1995 DWINSA and consisted of 60 

CWSs from New York and Texas. 

One change for the 2015 DWINSA is that EPA will deliver all data collection instruments electronically 

rather than mailing hard copies, as was done for the 1995, 1999, 2003, 2007 and 2011 DWINSAs. Several 

states received and used electronic data collection instruments in the 2011 DWINSA and states attending 

the May 2014 workgroup meeting expressed no concerns about using the electronic format. EPA 

therefore believes this approach has been well tested and has proven to be successful; therefore, it is not 

necessary to repeat this testing step. 

B.4 COLLECTION METHODS AND FOLLOW-UP

B.4.a Collection Method 

The proposed collection method is an electronic survey. The data collection instrument including the Lists 

of Codes will be sent to the states via e-mail. State drinking water agencies will provide the data 

collection instrument (with the project table prepopulated for systems that participated in 2011 and blank 

for those that did not) and other necessary documents to the systems in the sample. They will follow-up if 

the data collection instrument has not been returned in 30 days. For a complete description of the followup procedures proposed to increase the response rate, see section B.2.c.ii.

B.4.b Survey Response and Follow-up 

The target response rate (defined as the ratio of responses to eligible respondents) for the 2015 DWINSA 

is 90 percent. EPA realizes that this is an ambitious target, but EPA believes that there are special 

circumstances that warrant such a target. Also, overall response rates of 94, 97, 96, 93 and 97 percent

were achieved in the 1995, 1999, 2003, 2007 and 2011 surveys, respectively. In the first five surveys, 

EPA conducted the following activities to achieve that high response rate. 

 Seek Support from the Respondent Population. This is a national survey of infrastructure needs 

for drinking water systems. EPA will work to bring to the attention of water systems, as well as 

all national organizations representing these systems, the importance of the DWINSA results. As 
ICR for 2015 DWINSA 57 September 4, 2014

with the previous five surveys, all national organizations will be contacted by EPA to seek their 

endorsement of the DWINSA and to communicate to their members the importance of a high 

response rate to their members. As discussed in Section B.2.c, in past surveys, organizations have 

provided access to their newsletters and magazines to publicize and endorse participation in the 

DWINSA. For the 2015 Survey, EPA will seek similar efforts by these organizations.

 Follow-up by States and Respondent Peer Groups. Since a majority of states have indicated their 

willingness to participate in follow-up activities, EPA has requested that state personnel, most of 

whom are personally familiar with the respondents, conduct follow-up procedures including the 

use of reminder letters and telephone calls to systems that have not responded with the needed 

information or documentation. If the follow-up fails after three attempts (one reminder letter plus 

two telephone follow-up calls), EPA is planning to shift to a second approach of peer-group 

follow-up by members of a trade association, such as AWWA. 

B.5 ANALYZING AND REPORTING SURVEY RESULTS

B.5.a Data Preparation 

State personnel will check all cost data and documentation to ensure that it is consistent with state and 

national standards. States will then send the completed and reviewed data collection instruments to EPA 

for a second round of review by EPA contractor staff. 

Once data have been checked, the contractor will key and verify the data. Senior data entry staff will be 

used for the verification process to improve quality control. Editing will include automated logic and 

range checks and checks for missing data. Missing cost data will be modeled, using other information 

provided by the respondents on the data collection instrument. When modeling is insufficient, missing 

data will be imputed using standard methods such as cell means and regression. The sample of water 

systems will be weighted so that stratum estimates can be summed to prepare state-level estimates for the 

2015 DWINSA.

B.5.b Analysis 

EPA will prepare a report that tabulates the results of the 2015 DWINSA and explains the precision of the 

estimates of total capital needs. Examples of statistics that will be produced include:

 Total capital needs by state and by types of need.

 Total capital needs by domains within the total population, e.g., systems serving populations 

greater than 100,000.

 Standard errors calculated for key statistics.

The analysis will be similar to that of previous DWINSAs.

B.5.c Reporting Results 

The 2015 DWINSA results will be made available to EPA and the public through:

 A printed report that is submitted to Congress on drinking water infrastructure needs. This report 

will be made available to all participants in the 2015 DWINSA and the public through EPA’s 

Safe Drinking Water website. 
ICR for 2015 DWINSA 58 September 4, 2014

 Desktop computer access to state data on the DWINSA Web site without modeled project costs

(each state can access only its own data).

 Desktop computer access to the entire data system (EPA only).

A report providing the cost models used to develop costs for the 2015 DWINSA will be made available to 

EPA and the public through EPA’s Safe Drinking Water Web site.
ICR for 2015 DWINSA 59 September 4, 2014

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ICR for 2015 DWINSA 60 September 4, 2014

Appendix A – Public Notice Required Prior to ICR Submission to OMB
ICR for 2015 DWINSA 61 September 4, 2014

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ICR for 2015 DWINSA 62 September 4, 2014

Appendix B – Data Collection Instrument and Lists of Codes
ICR for 2015 DWINSA 63 September 4, 2014

OMB No.: 

Approval Expires: 

 U. S . E nvironment al P rot ec t ion A genc y Federal PWSID No.:

Please verify or correct the following information:

Name of System (Community): 

Name of Contact: 

Street Address: 

City, State, and Zip: 

Population Served (if wholesaler, 

include consecutive population 

as appropriate): 

Number of Connections (not 

including consecutive systems): 

Total System Design Capacity (in 

MGD): 

Total Length of Pipe in System 

(in Feet): 

Ground Surface/GWUDI

Purchased Ground Purchased Surface/GWUDI

Public Investor-Owned or 

Federal Government Private Non-Profit

State Reviewer: Telephone Number:

Washington, DC 20460

Check if Correct Corrected Information

as Printed

Source Water Type (Ground, Surface/GWUDI, etc.): 

Ownership Type: 

Check All That Apply:

Information provided for this survey can be requested by the public. It is our experience that this information is rarely requested.

Public reporting burden for this collection of information is estimated to average 5.53 hours per response. This estimate includes time for review ing the instructions, searching existing data sources, 

gathering and maintaining the data needed, and completing and review ing the information collected. Burden means the total time, effort, or financial resources expended by person(s) to generate, 

maintain, retain, or disclose or provide information to or for a Federal Agency. This includes the time needed to review instructions; develop, acquire, install, and utilize technology and systems for 

the purposes of collecting, validating, and verifying information; adjust the existing w ays to comply w ith any previously applicable instructions; search data sources; complete and review the 

collection of information; and transmit or otherw ise disclose the information. An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it 

displays a currently valid OMB control number. The OMB control numbers for EPA’s regulations are listed in 40 CFR Part 9 and 48 CFR Chapter 15.

Send comments on the Agency’s need for this information, the accuracy of the provided burden estimates, and any suggested methods for minimizing respondent burden, including through the use 

of automated collection techniques to the Director, OPPI, Regulatory Information Division, U.S. Environmental Protection Agency (1804A), Ariel Rios Building, 1200 Pennsylvania Ave., NW, 

Washington, DC 20460; and Office of Information and Regulatory Affairs, Office of Management and Budget, 725 17th Street, N.W., Washington, DC 20503.

State Use Only

Check All That Apply:

Needs Survey And Assessment

2015 Drinking Water Infrastructure

(Fill in only if preprinted information is missing or incorrect)
ICR for 2015 DWINSA 64 September 4, 2014

Project Table Federal PWSID No.: 

Project 

Number Project Name Type of Need 

Reason 

for Need N,E,R,H C or F

RegulationDesign 

Capacity Diameter Length Number Needed 

Cost 

Estimate 

Cost 

Date 

Documentation 

Remove 

M odify or 

Validate

Comment 

Codes

0
ICR for 2015 DWINSA 65 September 4, 2014

To ensure all potential source, treatment, and storage projects are considered, it may be helpful to complete some or all of this inventory table. 

How ever, completion of this table is not required.

 ▪ Source Projects are all projects related to collecting and pumping raw w ater. This includes w ells, surface w ater intakes, springs, off-stream raw 

 w ater storage, and pumps.

 ▪ Treatment Projects are all projects related to disinfection, filtration, or other treatment processes for ground or surface w ater sources, or for 

 treatment applied in the distribution system.

 ▪ Storage and Pumping Projects are related to finished or treated w ater storage, and booster pump stations.

Existing Raw Surface Water Pumps:

Source, Treatment, Storage, and Pumping Inventory

Source Water

Inventory Needing Replacement Needing Rehabilitation New Infrastructure Needs

For the sources identified above, enter the number of locations w here the follow ing treatment is applied: Does your system have additional treatment needs for 

provisions of additional public health protection or for 

aesthetic concerns?

Disinfection (including booster 

disinfection):

Disinfection:

Total Number and Capacity of Existing 

Wells or Springs: 

Wells (pumps included) or Springs: Wells (pumps included) or Springs: Does your system have additional source w ater capacity 

needs to meet the needs of current users?

Total Number and Capacity of Existing 

Surface Water Sources: 

Existing Surface Water Intakes 

(excluding pumps): 

Existing Surface Water Intakes (excluding 

pumps): If yes, how many additional sources are necessary?

Total Number and Capacity of Existing 

Pumps (excluding booster pump 

stations):

Existing Groundw ater Pumps (if w ells 

not listed):

Existing Groundw ater Pumps (if w ells not 

listed): 

Existing Raw Surface Water Pumps:

Filtration: Filtration:

Chemical removal or addition: Chemical treatment: Chemical treatment:

Treatment

Inventory Needing Replacement

Needing Expansion/Upgrading or 

Rehabilitation New Infrastructure Needs

Disinfection:

Total Number and Capacity of Existing 

Booster Pump Stations:

Number of Existing Booster Pump 

Stations: 

Number of Existing Booster Pump 

Stations: If yes, how much additional finished w ater storage or 

booster pumping capacity is necessary?

Storage and Pump Stations

Total Number and Capacity of Existing 

Storage Tanks: 

Number of Existing Elevated or GroundLevel Storage Tanks: Number of Existing Elevated or GroundLevel Storage Tanks:Does your system have additional storage capacity and/or 

booster pumping needs to meet the needs of current 

users?

Inventory Needing Replacement Needing Rehabilitation New Infrastructure Needs

If yes, how much additional treatment is necessary?

Filtration:

Yes No

Yes No

Yes No
ICR for 2015 DWINSA 66 September 4, 2014

Transmission and Distribution Inventory

On the table below , please provide an estimate of the total feet or miles of pipe in your system, if possible. Completion of this table is not required, but it may be helpful to

ensure all potential transmission and distribution pipe projects are considered.

 feet Total Pipe

 miles in System

(Check feet or miles)

Total Pipe in System

(Check feet or miles) <=6 inch 8-12 inch 15-42 inch >=48 inch

 feet 

 miles Amount of PVC by pipe size

 feet 

 miles

 feet 

 miles

 feet 

 miles

 feet 

 miles

% of total 

pipe

% of this category/size pipe 

currently in poor condition or 

beyond useful life % % % %

 feet 

 miles

Amount of ductile iron by pipe 

size

 feet 

 miles

 feet 

 miles

 feet 

 miles

 feet 

 miles

% of total 

pipe

% of this category/size pipe 

currently in poor condition or 

beyond useful life % % % %

 feet 

 miles Amount of cast iron by pipe size

 feet 

 miles

 feet 

 miles

 feet 

 miles

 feet 

 miles

% of total 

pipe

% of this category/size pipe 

currently in poor condition or 

beyond useful life % % % %

 feet 

 miles

Amount of asbestos cement by 

pipe size

 feet 

 miles

 feet 

 miles

 feet 

 miles

 feet 

 miles

% of total 

pipe

% of this category/size pipe 

currently in poor condition or 

beyond useful life % % % %

 feet 

 miles Amount of other by pipe size

 feet 

 miles

 feet 

 miles

 feet 

 miles

 feet 

 miles

% of total 

pipe

% of other currently in poor 

condition or beyond useful life % % % %

Cast Iron

Asbestos

Cement

Other

Transmission and distribution projects are the piping needs of a w ater system. Projects for valves, backflow prevention devices and assemblies, and meters that 

are not part of a transmission or distribution project listed in this table should be recorded in the table under the tab titled "Inventory Table 3".

Note: The total feet or miles or pipe in your system is required information if any pipe projects are 

submitted based solely on survey-generated documentation (documentation codes 10 or 11).

Plastic

Ductile

Iron
ICR for 2015 DWINSA 67 September 4, 2014

Meters, Service Lines, Backflow Prevention Devices/Assemblies, Valves, etc.

Projects for meters, service lines, backflow prevention devices and assemblies, valves, and other miscellaneous projects

are recorded in this section to accommodate entries of multiple identical items on one line in the project table. 

Record only projects that are not a part of another project (e.g., water main replacement projects will already include valves and other appurtenances). 

To ensure all potential projects are considered, it may be helpful to complete some or all of this inventory table. However, completion of this table is not required.

Total Number of Existing Water 

Meters:

Number of Water Meters: Number of Water Meters:

Total Number of Existing Backflow 

Prevention Devices/Assemblies:

Number of Backflow Prevention 

Devices/Assemblies:

Number of Backflow Prevention 

Devices/Assemblies:

Total Number of Valves: Number of Valves: Number of Valves:

Total Number of Lead Service Lines:

EPA requires documentation of all projects provided. Applicable types of documentation are presented in List 4 of the Lists of Codes. 

Use only existing documentation of cost. We do not expect you to develop new cost estimates.

Inventory Needing Replacement New Infrastructure Needs
ICR for 2015 DWINSA 68 September 4, 2014

Respondent Information

Telephone Number:

Fax Number:

E-mail Address:

Best Time to Reach You:

If you have any questions, contact your state coordinator.

CLOSING: Thank you for your help. Did you remember to?

Identify, by project number, available documentation for all needs and costs reported?

Email the questionnaire and email or mail the documentation to your state?

Please provide the following information in case we need to contact you for clarification or additional explanation of any of your responses.

Contact Person (Person who completed this questionnaire):

Signature:

Name (please print): 

Title:

Mailing Address:

(Street Address)
ICR for 2015 DWINSA 69 September 4, 2014

Summary of Survey-Generated and Independent Documentation for Each Project Federal PWSID No.: 0

Project 

Number Project Name 

Documentation 

Code(s)

State/System Survey-Generated Statement Independent 

Document Name

Independent 

Documentation 

Page Number(s)
ICR for 2015 DWINSA 70 September 4, 2014
ICR for 2015 DWINSA 71 September 4, 2014

Instructions for Each Column on the 2015 Drinking Water Infrastructure

Needs Survey and Assessment Questionnaire

Column Title Instructions

Project Number Number the projects in each category in sequence, using the following range of 

numbers for each category of need:

- 1000’s Source, treatment, storage, and pumping projects

- 2000’s Transmission and distribution projects

- 3000’s Meters, service lines, backflow prevention, valves, etc.

Project Name Provide a name that briefly describes and identifies the project. 

Type of Need Refer to List 1 in the Lists of Codes and enter the code(s) that best identifies the 

project. More than one code may apply to a project if a cost is provided. Use only one 

code if no cost is available. Codes not applicable to the 2015 DWINSA but that may 

appear in 2011 DWINSA data are shown in List 1 in italics and with strike-through to 

indicate they should not be used. 

Reason for Need Refer to List 2 in the Lists of Codes and enter the code(s) that best justifies the 

project. More than one code may apply to a project.

New,

Replace, 

Expand/Upgrade, 

or 

ReHabilitate

Identify whether the project is for:

- New infrastructure installation where none exists, enter ‘N’ 

Resulting infrastructure is entirely new.

- Replacement of existing infrastructure, enter ‘R’ 

Existing infrastructure is replaced with similar infrastructure.

- Expansion/Upgrade of a complete treatment plant, enter ‘E’

Major improvements to an existing complete plant that adds or changes unit 

processes or results in an increase in capacity. Only use for complete treatment 

plants.

- Rehabilitation of existing infrastructure, enter ‘H’ 

Restore existing infrastructure to near-new condition.

Current or Future Identify whether the project is:

- Needed now, enter ‘C’

(even if you cannot start construction now)

- Not needed now, enter ‘F’

(but will be necessary before 12/31/2034)

Regulation or 

Secondary Purpose

If the project is needed to maintain or obtain compliance with a regulation, secondary 

MCL, or state requirement, refer to List 3 in the Lists of Codes and enter the 

appropriate code. Enter ‘4A’ if no code applies.

Design Capacity Enter the design capacity when applicable:

- million gallons per day (MGD) for source, treatment, and pumping;

- million gallons (MG) for storage; 

- kilowatts (kW) for emergency power. 

For this survey, “design capacity” is the total volume or the flow that can be produced 

when all components of the project are operating (e.g., for disinfection, record the 

volume of water treated in MGD).
ICR for 2015 DWINSA 72 September 4, 2014

Column Title Instructions

Diameter Enter the diameter (in inches, using decimals) if the project is for pipe, valves, backflow 

prevention, or meters. Use a separate project number and line for different sizes of 

infrastructure if a documented cost is not available. Diameter is not needed for service 

lines.

Length Enter the length of pipe (in feet) that must be rehabilitated, replaced, or installed as new. 

Use a separate project number and line for different sizes of pipe if a documented cost is 

not available.

Number Needed If you have multiple identical projects at the same capacity or multiple identical items, 

indicate the total number needed (e.g., rehabilitate 10 wells each with a 0.5 MGD 

capacity, or replace 1,000 0.625-inch meters).

If you use this column and provide a project cost, the cost should reflect the entire 

project (i.e., all 10 wells or all 1,000 meters, not the cost of an individual well or meter).

Cost Estimate If an existing cost estimate is available, enter the documented cost estimate for this 

project. Do not use cost estimates that were prepared prior to January 1, 2005. If no cost 

estimate is provided and modeling parameters are recorded, EPA will use models to 

estimate the cost. Do not develop a cost estimate for this survey.

Cost Date If a documented cost estimate is provided, enter the month and year (MM/YYYY) of the 

cost estimate. EPA will adjust costs to current-year dollars.

Documentation Refer to List 4 in the Lists of Codes and enter the code(s) that applies to the type of 

documentation provided that explains why the project is needed. If a cost estimate is 

provided, also enter the code that applies to the type of cost documentation. More than 

one code may apply to a project. 

Remove, Modify, or 

Validate

This column appears for systems that participated in the 2011 DWINSA. An asterisk (*) 

indicates the project must be removed, modified, or have a project-specific validation for 

the 2015 DWINSA.

This page is intentionally left blank.

Important Notes:

o What is a “need”? Installation or rehabilitation of capital infrastructure needed over the next 20 years to 

obtain or maintain service to existing customers or to existing homes with inadequate or unsafe water 

that are not currently connected. Projects substantially for meeting anticipated future population growth or 

for fire flow are not allowed for the DWINSA.

o What is “independent documentation”? Documents generated through a process independent of the 

DWINSA (e.g., CIP, master plan, sanitary survey report).

o What is “survey-generated documentation”? Documents generated specifically for the survey that are 

written by the system or the state.

Please use the Documentation Summary tab of the Questionnaire to provide survey-generated 

documentation of need and/or provide information on the independent documentation for the project. A 

description of each project or a copy of the documentation must be provided and be clearly identified by project 

number. 
ICR for 2015 DWINSA 73 September 4, 2014

LIST 1 - TYPE OF NEED

Code Type of Need

RAW/UNTREATED WATER SOURCE 

R1 Well (including pump and appurtenances)

R2 Well Pump

R3 Well House 1

R4 Eliminate Well Pit 1 

R5 Abandon Well 1

R6 Aquifer Storage and Recovery Well 

R7 Surface Water Intake 

R8 Raw Water Pump

R9 Off-Stream Raw Water Storage 2

R10 Spring 

R11 Destratification 1

TREATMENT: Disinfection

T1 Chlorination

T2 Chloramination

T3 Chlorine Dioxide

T4 Ozonation

T5 Mixed Oxidant Type Equipment

T6 Ultraviolet Disinfection

T7 Contact Basin for CT

T8 Dechlorination of Treated Water

T9 Chlorine Gas Scrubber

TREATMENT: Complete Plants (N/R/E require independent documentation)

T10 Conventional Filter Plant (includes CAC technologies)

T11 Direct or In-line Filter Plant 

T12 Slow Sand Filter Plant 

T13 Diatomaceous Earth Filter Plant 

T14 Membrane Technology for Particulate Removal 

T15 Cartridge or Bag Filtration Plant 

T16 Lime Softening 

T17 Reverse Osmosis 

T18 Electrodialysis 

T19 Activated Alumina 

T20 Manganese Green Sand (or other oxidation/filtration technology) 

T21 Ion Exchange 

T22 Groundwater Chemical-feed

T23 Iron Adsorption

T24 Aeration 

TREATMENT: Other Components / Equipment / Processes 

T30 Zebra Mussel Control 

T31 Corrosion Control (chemical addition)

T32 Powdered Activated Carbon 

T33 Aeration (component)

T34 Sequestering for Iron and/or Manganese 

1 These codes are not applicable to the 2015 DWINSA but may appear in 2011 DWINSA data.

2 Cost must be provided; cost of this infrastructure cannot be modeled.
ICR for 2015 DWINSA 74 September 4, 2014

LIST 1 - TYPE OF NEED (cont.)

Code Type of Need

TREATMENT: Other Components / Equipment / Processes

T35 Chemical Feed 

T36 Chemical Storage Tank

T37 Fluoride Addition

T38 Presedimentation Basin

T39 Sedimentation/Flocculation

T40 Granular Activated Carbon

T41 Membrane Filtration (not complete plant)

T42 Media Filters

T43 Waste Handling/Treatment: Mechanical (not included in another project)

T44 Waste Handling/Treatment: Nonmechanical or Connection to a Sanitary Sewer 

(not included in another project)

T45 Type of Treatment Unknown

T46 Other (Please include an explanation) 2

TRANSMISSION MAINS: (Any mains that transport raw water to the treatment plant, or treated water from the plant to the 

distribution system grid.)

X1 Raw Water Transmission

X2 Finished Water Transmission

DISTRIBUTION

M1 Distribution Mains (any mains that transport water through a piping grid serving customers; see "transmission" above)

M2 Lead (Pb) Service Line Replacement

M3 Service Lines (other than lead service lines)

M4 Hydrants 1

M5 Valves (gate, butterfly, etc.) (not included in a pipe project) 

M6 Control Valves (PRVs, altitude, etc.)

M7 Backflow Prevention Devices/Assemblies

M8 Water Meters

FINISHED/TREATED WATER STORAGE

S1 Elevated Finished/Treated Water Storage

S2 Ground-level Finished/Treated Water Storage

S3 Hydropneumatic Storage

S5 Cover for Existing Finished/Treated Water Storage 

PUMP STATION AND FINISHED WATER PUMP

P1 Finished Water Pump

P2 Pump Station (booster or raw water pump station-may include clearwell, pumps, housing)

OTHER INFRASTRUCTURE NEEDS

W1 Laboratory Capital Costs for Labs Owned by the System 1

W2 Computer and Automation Costs (SCADA)

W3 Pump Controls/Telemetry 1

W4 Emergency Power (enter design capacity as kilowatts)

W5-W9 Fencing and Security-related needs 1

W10 Other (Please include an explanation) 2
ICR for 2015 DWINSA 75 September 4, 2014

LIST 2 - REASON FOR NEED

Code Reason the Project is Needed

A1 Project is for existing infrastructure that is or will be old or deteriorated by 12/31/2034.

A2 Project is to correct a deficiency in source water quantity caused by current user 

demand.

A3 Project is to correct a deficiency in storage capacity caused by current user demand.

A4 Project is to correct existing pressure problems (not related to fire flow).

A5 Project needed as a result of, but not in preparation for, a natural disaster.

A6 Project is to obtain or maintain compliance with an existing regulation (enter the 

regulation code from List 3 in the Lists of Codes in the regulation column of the 

questionnaire).

A7 Project is to obtain or maintain compliance with a secondary standard (e.g., iron, taste 

and odor, and color) (enter regulation code 2A in the regulation column of the 

questionnaire).

A8 Project is for consolidation with and/or connection to an existing public water system.

A9 Project is for extending service to existing homes without adequate water quantity or 

quality. 

A10 [A10 is not applicable to the 2015 DWINSA but may appear in 2011 DWINSA data. A10 

referred to security-related needs]

A11 Use this code if codes A1-A9 do not apply. 
ICR for 2015 DWINSA 76 September 4, 2014

LIST 3 - REGULATION OR SECONDARY PURPOSE

Code Regulation or Secondary Purpose

EXISTING SDWA REGULATIONS

1A Surface Water Treatment Regulations (Surface Water Treatment Rule, Interim Enhanced Surface 

Water Treatment Rule, Filter Backwash Recycling Rule, Long Term 1 Enhanced Surface Water 

Treatment Rule, or Long Term 2 Enhanced Surface Water Treatment Rule)

1B Total Coliform Rule or Revised Total Coliform Rule

1C Nitrate or Nitrite Standard

1D Lead and Copper Rule 

1E Arsenic Rule 

1F Stage 1 or Stage 2 Disinfectants/Disinfection Byproducts Rules 

1G Other Regulated VOCs, SOCs, IOCs, or Radionuclides (excludes Radon)

1H Ground Water Rule

OTHER 

2A Secondary Contaminants (e.g., iron, taste and odor, or color)

2B State Requirements

IF NONE OF THE ABOVE CODES APPLY

4A Use this code if none of the codes above apply 

PROPOSED AND RECENTLY PROMULGATED SDWA REGULATIONS

Needs associated solely with the Proposed Radon Rule are not allowable and should not be 

included. The costs for these needs, estimated for the rule’s Economic Analysis, will be added to 

the total national need. 

As of January 1, 2015, there were no other proposed rules or recently promulgated rules applicable 

to the 2015 DWINSA. 
ICR for 2015 DWINSA 77 September 4, 2014

LIST 4 - DOCUMENTATION

Code Independent Documentation of Need and/or Cost

1 Capital Improvement Plan or Master Plan. The plan must address why the project is needed and/or 

provide a cost.

2 Facilities Plan or Preliminary Engineering Report. Excerpts justifying need and/or cost from the plan or 

report are acceptable if project-specific.

3 Grant or Loan Application Form. An application form is acceptable if it specifically describes a problem 

requiring capital expenditures.

4 Engineer's Estimate or Bid Tabulation. These must be project specific and independently generated. 

They must also be accompanied by an explanation of why the project is needed. 

Code Independent Documentation of Need Only

5 Intended Use Plan/State Priority List. The excerpts must include a description of why the project is 

needed. Costs from IUPs will not be used - modeling parameters or other cost documentation must be 

provided.

6 Comprehensive Performance Evaluation (CPE) or Sanitary Survey Results. The results or 

recommendations may be used to justify need if the state concurs.

7 Monitoring Results. Monitoring results indicating an MCL exceedance or a trending toward an 

exceedance can demonstrate a need for a project if accompanied by a written statement explaining how 

the results demonstrate the need.

8 Other Independent Document. Use this code if documentation is independent but none of the codes 

listed above apply. Examples include: state enforcement order/notice of violation, engineering studies, 

water main break report, repair reports, and distribution system studies.

Code Independent Documentation of Cost Only

9 Cost of Previous Comparable Construction. This may be used to justify costs if the costs are projectspecific. It must include documentation of how the costs were derived. 

Code Survey-generated Documentation of Need Only

10 Written by State. Brief description and statement of need written by the state.

11 Written by System. Brief description and statement of need written by the system.

Code Documentation Submitted for Previous DWINSA

20 Project Relied on 2007 DWINSA Documentation. Code not applicable to the 2015 DWINSA. Resubmit 

documentation if it is needed.

21 Project Relies on 2011 DWINSA Documentation. Submit project-specific validation statement. Other 

documentation codes also apply if additional documentation is submitted for the 2015 DWINSA.
ICR for 2015 DWINSA 78 September 4, 2014

Appendix C – Comments and Response to Comments Received on the 2015 

DWINSA Peer Review
ICR for 2015 DWINSA 79 September 4, 2014

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ICR for 2015 DWINSA 80 September 4, 2014

Introduction to the 2015 DWINSA Peer Review Comment and Response

EPA has assessed the drinking water infrastructure needs of public water supplies through a national 

survey of drinking water systems every four years since 1995. Using a stratified random statistical sample 

of water systems, the Agency assesses need by evaluating project-level data from each system sampled 

including information about the type of project, its size or capacity, and its cost. A new sample was 

selected for each Assessment and the same basic approach (with some notable exceptions) was used in 

1995, 1999, 2003, 2007 and 2011. 

EPA proposes using a different statistical approach for the design of the 2015 Drinking Water 

Infrastructure Needs Survey and Assessment (DWINSA or Assessment). Rather than select a completely 

new sample of systems in 2015, EPA proposes to survey the participants in the 2011 Assessment and reassess their 20-year investment need in 2015. By using information from the 2011 review as a starting 

point, this panel approach would reduce the amount of time required to review each system’s response 

and would allow for analyses of trends. The sample will be “refreshed” by randomly selecting up to 25 

percent of the 2011 sample in each stratum to be dropped and placed back in the pool of systems that 

were not selected in 2011. Systems will then randomly be selected from among the pool of systems that 

were not in the 2011 sample and the systems that were dropped.

The proposed panel (or longitudinal) approach, which tracks a cross-section of observations over time, is 

common in econometric studies and is used to study individuals, households, firms and utilities. It 

provides advantages in terms of costs while allowing for trend analyses and providing probability samples 

of systems on which estimates of each state’s needs can be based. 

EPA asked two statisticians to review the proposed approach. The peer review charge is to assess the 

proposed panel approach as outlined in the document: Proposed Panel Study Approach to the 2015 

Drinking Water Infrastructure Needs Survey and Assessment. The approach was reviewed internally by 

Dennis Guignet, Ph.D., of EPA’s National Center for Environmental Statistics. It also was reviewed by 

Don L. Stevens Jr., Ph.D., of Stevens Environmental Statistics. Each reviewer’s comments and EPA’s 

responses are provided below. The comments are presented without attribution by name to either 

reviewer.
ICR for 2015 DWINSA 81 September 4, 2014

Reviewer # 1

I. GENERAL IMPRESSIONS

The general approach of using a partial replacement panel study is eminently sensible for studies with 

dual objectives of estimating status and trends. Besides the potential cost savings of reducing the review 

cost, trend estimates can be more precise because of elimination of a component of variance. 

There is no indication of plans to continue the panel approach beyond 2015. The full potential of a panel 

design can only be realized if it is kept in place for multiple surveys. The current plan should address this 

and also specify how the sample will be “refreshed” in subsequent years.

EPA response: EPA recognizes the longer-term potential offered by the panel approach and will evaluate 

its future use, including the use of the refresh, in conjunction with the completion of the 2015 Survey.

Neyman allocation is a reasonable approach, but some of the resulting sample sizes in the 2011 table 

seem a bit extreme. For example, New York was allocated a sample of 3 from 123 small ground water 

systems, but Nevada was allocated a sample of 3 from 4 small surface water systems. Was the variation 

really that extreme? While Neyman allocation is theoretically optimal, that’s only the case if the real 

variance is known. In practice, the variance is always estimated, and hence has some uncertainty, 

especially variance based on small sample sizes. It appears as if “3” were set as a minimum sample size; 

if, so, I think that’s too small. 

EPA response: The allocation of each state’s sample by strata depends on the variance, the 

number of systems in each stratum and the share of the total need in the census strata (systems 

serving more than 100,000 persons). To determine the sample size needed per state and to 

allocate the sample among the strata, we must estimate the variance and total need for each state. 

We use data from prior Assessments to estimate the total need and variance. In both New York 

and Nevada, systems serving more than 100,000 account for more than 80 percent of total need, 

even though they comprise less than 10 percent of the systems. 

Because systems serving more than 100,000 persons account for such a large share of the total 

need, the Neyman allocation often requires very few systems—2, 1 or fewer—per stratum. The 

sampling plan requires at least 3 systems per strata. (We need at least 2 systems per stratum to 

calculate the standard error and select 3 to allow for non-response.) 

II. RESPONSE TO CHARGE QUESTIONS 

1. Sampling Plan/Statistical Theory

a. Are there any general comments or noticeable flaws with the proposed panel study approach?

The proposal is to refresh 25% of the sample. Many sample sizes are small and not divisible by 4. The 

proposal should specify how the dropped sites are to be selected if, for example, the sample size is 7.

EPA response: The study will round the number to be resampled to the nearest integer. If a 

stratum has seven systems in the sample we will resample two systems. 

b. Is the proposed panel study approach complete?

It was not clear how actual needs data was to be collected for the states retained from the 2011 sample. 

Are the states asked to update their 2011 response? Accurate needs data is critical to the success of the 

panel approach. In the usual application of a panel study, the retained elements are re-measured along 
ICR for 2015 DWINSA 82 September 4, 2014

with the new elements. Point 4 in the “Proposed Survey Approach” seems to suggest that the process for 

new and retained systems will be different. This could be a serious problem unless the “rules” EPA has 

yet to develop in fact yield comparable needs data.

EPA response: The systems retained from the 2011 survey will be asked to update their 2011 

response. The guidelines ensure that only needs allowable under the Drinking Water State 

Revolving Fund (DWSRF) are included in the survey. These guidelines and the EPA’s review of 

the systems’ responses ensure they are consistent with prior surveys and with the new systems 

added to the survey. 

c. Is the statistical theory the correct approach and does it give the desired results?

The statistical theory is correct. Depending on how the response for sites not replaced is determined, the 

estimates should be acceptable. However, because of constraints on refreshing 25% of a small sample, the 

desired cost savings may not be realized.

EPA response: EPA recognizes that the 25% refresh will reduce the potential savings associated 

with the panel approach.

2. Will EPA’s approach for the 2015 Assessment to “refresh 25% of the 2011 sample with new systems 

from the 2011 sample” adequately:

a. Represent system needs for 2015?

It depends on how the cost data for the non-replaced systems is determined. As I noted above, the 

proposal was not clear on that point. If the cost data is correct for 2015, then the system needs for 2015 

should be adequately represented.

EPA response: See above.

b. Address states concerns that their allotment is too closely tied to the 2011 Assessment and help 

alleviate a potential source of bias?

See my response above. I’m not sure what “potential source of bias” is present. Provided the needs data is 

correct for 2015, then the results are unbiased.

3. As part of the panel approach, EPA is planning on keeping the size of the sample of medium systems 

the same as in 2011. Should it adjust the sample size if necessary to meet the desired precision targets, 

or should it keep the sample size the same as in 2011?

The sample size should be adjusted to meet precision targets. The sample sizes were based on Neyman 

allocation, sometime with variance estimates based on very small samples. As more (better) information 

becomes available on variation, the sample allocation should certainly be reconsidered.

EPA response: In 2011, the sample was designed to meet a precision target of plus or minus 10 

percent of the total need for each state. Data from 2003 and 2007 were used to estimate the 

variance in order to calculate the required sample sizes. EPA will update its estimates of the 

variance using the data from the 2011 Assessment.

The sample size needed in 2015 can change because of changes in the inventory or changes in the 

estimated variance of total need by state. In principal, the required sample size can increase or 

decrease due to these changes. The sample for some states may increase while others may 
ICR for 2015 DWINSA 83 September 4, 2014

decrease. The allocation among a state’s strata may also change, even if the total sample 

required does not change. 

EPA will revise the sampling plan based on this comment. In cases where the sample size needed 

increases, EPA will drop 25 percent of the 2011 sample, returning the dropped systems to the 

pool of systems that can be sampled. EPA will then randomly select the number of additional 

systems required to meet the precision targets. For example, if the 2011 sample size was 12 and 

the 2015 sample size must increase to 15 to meet the precision target, EPA will first randomly 

select and drop 3 systems from the sample and will then randomly select 6 systems from the 

inventory of remaining systems. The three systems that were dropped may get sampled again. 

In cases where the required sample size decreases, EPA will randomly select systems to remove 

from the sample. It will then randomly select 25 percent of the remaining sample to drop and 

replace. EPA will then randomly select from the frame—including systems that were dropped in 

the first two steps—systems to replace the 25 percent dropped as part as the refresh. 

III. SPECIFIC OBSERVATIONS

Page Paragraph Comment or Question

5 3 It is a mistake not to re-evaluate sample sizes based on revised variance 

estimates or frame changes. 

EPA response: See response to 3, above.

6 b P4, paragraph 4, suggests that the new systems would have a separate 

supplemental sample. This paragraph suggests that the new systems will be 

included in the frame for the replacement systems. Which is the case?

EPA response: We will clarify the language and revise P4 paragraph 4.

Systems added to inventory will be included in the frame for the 

replacement systems and will have a chance of being selected as part of the 

refresh.

6 4 The “rules for how projects are included in the 2011 Assessment” are 

critical. If this is not done carefully, than the whole study could be 

compromised.

EPA response: EPA recognizes the importance of the rules that guide 

project review. 
ICR for 2015 DWINSA 84 September 4, 2014

Reviewer # 2

In responding to the below charge questions, my review focuses on adapting the previously peer-reviewed 

2011 sampling design to accommodate a panel data approach. Although I reviewed much of the 2011 

sampling plan to gather background information, my comments below focus only on the proposed 

changes for the 2015 sampling plan. 

1. Sampling Plan/Statistical Theory 

a. Are there any general comments or noticeable flaws with the proposed panel study approach?

Overall, the proposed changes to the 2011 sampling plan to accommodate the collection of a panel dataset 

seem reasonable, and I find no major flaws based on my review. Statistical theory suggests that the 

stratified random sample of medium facilities chosen in 2011 was representative of facilities at that time. 

It stands to reason that this same sample is still representative of the population of medium systems in 

2015. 

Besides minor considerations discussed in my below responses, I think the proposed panel approach is 

valid and offers several advantages. In addition to the cited cost-savings and reduced burden to the EPA 

and Water Systems, a panel data approach increases EPA’s ability to analytically assess the effectiveness 

of funds in completing projects, to examine how cost estimates for individual projects evolve over time 

and the initial accuracy of estimates derived by individual water systems or EPA, and to potentially 

distinguish between total costs projected over the next 20 years versus incremental costs relative to 

previous assessments. 

EPA response: Following completion of the 2015 DWINSA, we will be assessing these possible 

future benefits of the new approach in designing the 2019 effort.

b. Is the proposed panel study approach complete?

Yes, the proposed panel approach is complete. My only suggestion is that EPA establish their decision 

rules for “how projects included in the 2011 Assessment will be reviewed and how new projects will be 

handled” (pg 6), and that this be made clear beforehand. No details are currently provided with the 

proposed panel approach plan.

These decision rules are particularly important given that the requested fields (e.g., “project name”) are 

open-ended, which could lead to slight differences in responses for the same project. Additionally, it is 

seems possible that the Water System and EPA staff who filled-out and reviewed the survey in 2011 may 

not be the same individuals in 2015. 

Perhaps it would be worthwhile to send previous survey responses to systems along with the 2015 

survey? If systems have their last list of projects in front of them, then this may minimize the potential for 

unwanted overlap and help encourage consistent project names, etc. across the two time periods in the 

panel. At the same time, this would be a systematic difference between the panel sample compared to the 

2015 “refresh” sample, and so consideration should be given to any potential biases that could 

inadvertently triggered if the previous 2011 responses were provided. In any case, since the census of 

large systems is already a panel dataset, if such inconsistency issues were not an issue there, then perhaps 

the above concern is not warranted in the context of medium sized systems either. 

EPA response: EPA recognizes the importance of the rules for how projects are reviewed and 

how new projects will be handled. The systems retained from the 2011 survey will be asked to 

update their 2011 response. EPA will send systems that participated in the 2011 survey their 
ICR for 2015 DWINSA 85 September 4, 2014

responses to the survey as a starting point for the 2015 assessment. Guidelines will ensure that 

only needs allowable under the DWSRF are included in the survey. These guidelines and the 

EPA’s review of the systems’ responses ensure they are consistent with prior surveys and with the 

new systems added to the survey. 

c. Is the statistical theory the correct approach and does it give the desired results?

Yes, the statistical theory appears correct. However, if the desired results are to estimate the 95% 

confidence of total need by state with a 10% level of precision, then this may not necessarily be obtained. 

Please see response to item 3.

EPA response: EPA will adjust the size of the sample to allow for changes in the inventory of 

water systems as well as revisions to estimates of the variance in need. See the response to item 3, 

below. 

2. Will EPA’s approach for the 2015 Assessment to “refresh 25% of the 2011 sample with new systems 

from the 2011 sample” adequately:

a. Represent system needs for 2015?

Yes, the proposed panel approach should provide a representative sample of system needs for 2015, even 

absent the 25% sample refresher. The 25% refresher will further ensure a representative sample.

Statistical theory suggests that the stratified random sample of medium facilities chosen in 2011 was 

representative of facilities at that time. It stands to reason that this same sample is still representative of 

the population of medium systems in 2015. One potential flaw in this thought is if these stratified 

randomly selected facilities become inherently different from the population of other medium systems 

within their strata in between 2011 and 2015. For example, if a facility’s particular needs systematically 

change as a result of previously filling out the survey, then the sample could be less representative of the 

population within that strata. If there is any reason to suspect that a facility’s allocation of funds, 

effectiveness in spending funds, or even how they fill-out the survey, are systematically different due to 

the fact that that particular facility filled out a survey in 2011, or that they know they may fill out future 

surveys, then this could lead to potential biases in the 2015 sample. 

However, no evidence was presented suggesting that this could be the case, and the introduction of a 25% 

sample “refresher” within each strata should alleviate concerns along these lines. Furthermore, by 

comparing the “refreshed” sample to the sample of systems included in both the 2011 and 2015 sample, 

one can statistically test whether such facilities are similar (e.g., t-tests of mean responses across 

subsamples). Although, such tests likely require the pooling of systems across strata in order to achieve 

the desired level of statistical power, such comparisons may still be insightful. With the appropriate 

caveats such comparisons could shed light onto the validity of the panel approach and the need (or lack of 

a need) for a sample “refresher” in future surveys beyond 2015.

EPA response: EPA recognizes the potential bias that can be introduced by asking systems to 

report their project need again. Systems may have learned from their experience in the 2011 

Assessment and change their estimate of their future needs as a result. This potential source of 

bias is not new as systems serving more than 100,000 have participated in every survey since the 

initial assessment in 1995. There is no evidence that large systems’ responses have been affected 

by their long-term participation in the survey. Furthermore, many medium systems have been 

included in more than one Assessment and their responses generally appear to be consistent with

medium systems of similar size and type that have not been included in more than one 

Assessment. 
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b. Address states concerns that their allotment is too closely tied to the 2011 Assessment and help 

alleviate a potential source of bias?

I was not provided with any documentation of the States’ comments or concerns, but I presume that such 

concerns stem from the fact that a “bad” draw of the random sample for a State could lead to concerns 

that the State’s total allotment is too closely tied to the sample selected in 2011. If this is the case, then 

such concerns could be aggravated by the fact that this same sample would be used to assess their needs 

in 2015. That said, these samples are randomly drawn from within each strata. No matter when a sample 

is drawn (2011 or 2015), the States have a similar probability of getting a more or less “favorable” draw. 

Such discrepancies are random, and are an inherent component of any statistical sampling plan. This 

should not lead to any systematic biases, however, in estimating State needs.

All that said, since the 25% refresh is again a random selection of systems within each strata, this will 

help alleviate any potential concerns and perhaps even provide an opportunity to statistically test whether 

such concerns are warranted (see response to item 2a above). 

EPA response: EPA is implementing the 25 percent refresh in light of discussions with states and 

to address issues also noted by the reviewer.

3. As part of the panel approach, EPA is planning on keeping the size of the sample of medium systems 

the same as in 2011. Should it adjust the sample size if necessary to meet the desired precision targets, 

or should it keep the sample size the same as in 2011?

On page 5 of the “Proposed Panel Study” document it states that “EPA will not change the sample sizes 

to account for revised estimates of the variance in system need or changes in the inventory of medium 

systems.” Keeping the sample the same size each time period within a panel dataset may be an attractive 

feature, but if this is the preferred path some additional justification should be provided. If the desire is to 

continue to maintain a 10% level of precision then it seems that the sample size should be adjusted to 

account for changes in the size of the population of systems within the different strata, as well as the 

within strata variance. 

For example, in instances where the population of facilities within a strata increases, based on equations 

2.2 through 2.5 in Appendix 2 of the “Proposed Panel Study” document, it seems necessary to increase 

the sample size within the respective strata in order to maintain a 10% level of precision. I’m not arguing 

that the sample sizes should necessarily be changed in response to any changes in the number of systems 

in the population, but if the 2011 samples sizes were maintained in 2015, then this needs to be made 

transparent and the appropriate caveats should be included. Most notably, claims of 10% precision should 

not be made if that is not the level of precision obtained when keeping the sample size the same as that in 

2011. 

On a similar note, it appears that an optimum allocation design was used to determine the sample size and 

allocation across strata, which accounts for information obtained from previous surveys (i.e., estimated 

standard deviation within each strata and total state costs). On page 20 of the “Proposed Panel Study” 

document, it is stated that in determining the 2011 sample sizes, this information was estimated based on 

data from the 2003 Assessment; in other parts it states 2007. I presume this should always read as 2007, 

but if not then it is unclear why the 2007 Assessment was not used as this was the most recent data prior 

to the 2011 survey. 

In any case, it seems that state cost and stratum standard deviation estimates can be obtained based on 

information obtained from the 2011 survey, which in turn would provide a more current determination of 

the sample size and allocation needed to obtain the desired precision targets. Perhaps doing so in a panel 
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structure introduces some issues that I am not aware of, but this may be something worth considering in 

order to minimize survey costs and obtain the desired level of precision. 

EPA response: It 2011, the sample was designed to meet a precision target of plus or minus 10 

percent of the total need for each state. Data from 2003 and 2007 were used to estimate the 

variance in order to calculate the required sample sizes. EPA will update its estimates of the 

variance using the data from the 2011 Assessment.

The sample size needed in 2015 can change because of changes in the inventory or changes in the 

estimated variance of total need by state. In principal, the required sample size can increase or 

decrease due to these changes. The sample for some states may increase while others may 

decrease. The allocation among a state’s strata may also change, even if the total sample 

required does not change. 

EPA will revise the sampling plan based on this comment. In cases where the sample size needed 

increases, EPA will drop 25 percent of the 2011 sample, returning the dropped systems to the 

pool of systems that can be sampled. EPA will then randomly select the number of additional 

systems required to meet the precision targets. For example, if the 2011 sample size was 12 and 

the 2015 sample size must increase to 15 to meet the precision target, EPA will first randomly 

select and drop 3 systems from the sample and will then randomly select 6 systems from the 

inventory of remaining systems. The 3 systems that were dropped may get sampled again. 

In cases where the required sample size decreases, EPA will randomly select systems to remove 

from the sample. It will then randomly select 25 percent of the remaining sample to drop and 

replace. EPA will then randomly select from the frame—including systems that were dropped in 

the first two steps—systems to replace the 25 percent dropped as part as the refresh. 

Other minor comments that may be worth some consideration:

 One minor point regarding the assessment of small systems. On page 6, it states that “Systems 

that serve populations fewer than 3,301 will not be surveyed. Their needs will be based on the 

average system need as calculated in 2011...” The Office of Ground Water and Drinking Water 

certainly has a better understanding of this than I, and I ultimately defer to their expertise, but my 

understanding is that in 2011 the average small system needs were inferred from responses to a 

2007 survey. Are there any concerns that these data are 8 years old and small system needs may 

have changed?

EPA response: In previous assessments, EPA has successfully used the approach of 

extrapolating earlier survey results based on adjustments for construction cost inflation and 

shifts in the number and sizes of small water systems. For the 2015 assessment, EPA believes

this approach will provide an accurate accounting of these systems’ needs, but upon 

completion of the 2015 effort, the Agency will evaluate the results in the context of designing 

the 2019 DWINS.

 On page 22, equation 2.6, a slight adjustment is made to account for an assumed 90% response 

rate. However, the 2011 medium facility response rate was listed as 97%. It seems EPA is being 

conservative by assuming lower response rate than it has achieved in the past. It seems reasonable 

to be conservative in order to better ensure the desired level of statistical precision. Perhaps this is 

a feature worth emphasizing? 
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EPA response: While we will work to continue to have a higher response rates, EPA will 

continue to be conservative in setting targeted sample sizes to ensure our precision targets 

are reached and a credible survey obtained.
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Appendix D – Comments and Response to Comments Received on the First 

Federal Register Notice
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