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PUBLIC OPINION OF POTABLE WATER REUSE IN DENVER, COLORADO
By
BRANDI LEIGH HONEYCUTT
B.S., University of North Carolina, Asheville, 2004
A thesis submitted to the
Faculty of the Graduate School of the
University of Colorado in partial fulfillment of
the requirements for the degree of
Master of Science Environmental Science
2015
© 2015
BRANDI LEIGH HONEYCUTT
ALL RIGHTS RESERVED
ii
This thesis for the Master of Science degree by
Brandi Leigh Honeycutt
has been approved for the
Department of Geography and Environmental Science
by
Gregory Simon, Chair
Peter Anthamatten
Brian Good
November 18, 2015
iii
Honeycutt, Brandi Leigh (M.S., Environmental Science)
Public Opinion of Potable Water Reuse in Denver, Colorado
Thesis directed by Associate Professor Gregory Simon
ABSTRACT
Potable water reuse is becoming a more prevalent water supply augmentation
option as water utilities face supply threats from climate change, drought and population
growth. Potable water reuse involves purifying municipal wastewater to drinking water
quality and reusing the water for potable purposes. Public acceptance of potable water
reuse is one of the most important factors driving potable reuse projects and lack of
adequate public support has led to project failure. Water reuse professionals recommend
that public opinion surveys regarding potable reuse are executed and maintained in
regions that may implement potable reuse in the future. Since potable water reuse could
help to alleviate water supply pressures in Denver, Colorado, an online public opinion
survey was performed in the Denver metropolitan area. Major findings reveal that the
Denver metro area public values environmental benefits, drought and climate change
resiliency from implementing potable water reuse. Additionally, potable water reuse that
involves storing the recycled water in an environmental buffer for some time prior to
retreating it and using it for potable purposes is preferred. Finally, most of the
respondents were comfortable with water reuse applications that do not involve ingesting
the water.
The form and content of this abstract are approved. I recommend its publication.
Approved: Gregory Simon
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ACKNOWLEDGEMENTS
I would like to thank the Rocky Mountain Section American Water Works Association
for granting me the James B. Warner Scholarship worth $2,000 that helped fund this
research. I am especially grateful for Mr. and Mrs. Warner for their contribution and
support.
I also extend the upmost gratitude to my committee members, Dr. Gregory Simon, Dr.
Peter Anthamatten and Deputy Manager of Denver Water Brian Good for their guidance
and contribution to my completion of this research.
Last but not least, I appreciate Denver Water’s financial support and for providing me
with a flexible schedule, which enabled me to complete the course work for this degree.
v
TABLE OF CONTENTS
CHAPTER
I. INTRODUCTION AND BACKGROUND .................................................................... 1
Non-Potable Reuse ...................................................................................................................... 8
Indirect Potable Reuse ............................................................................................................... 10
Direct Potable Reuse ................................................................................................................. 11
II. LITERATURE REVIEW OF DIRECT POTABLE REUSE AND PUBLIC ACCEPTANCE ................................................................................................................ 13
DPR Facilities in Existence ....................................................................................................... 14
Review of Public Acceptance of Water Reuse .......................................................................... 17
Success and Failure of Potable Water Reuse Implementation .............................................. 17
Factors Influencing Success of Potable Water Reuse Implementation ................................. 21
Survey Findings on Public Perception of Water Reuse ........................................................ 23
Context of Research................................................................................................................... 29
III. METHODOLOGY ..................................................................................................... 35
Subjects...................................................................................................................................... 35
Denver Metro Area Public .................................................................................................... 35
Denver Water Employees...................................................................................................... 36
Instrumentation .......................................................................................................................... 36
Content .................................................................................................................................. 37
Design ................................................................................................................................... 38
Data Analysis ........................................................................................................................ 40
IV. RESULTS ................................................................................................................... 41
Descriptive Statistics ................................................................................................................. 41
Demographic Attributes ........................................................................................................ 41
Other Respondent Characteristics ......................................................................................... 42
Water Supply Ranks .............................................................................................................. 44
Support for IPR, DPR and Statements Regarding DPR ........................................................ 44
Analyses .................................................................................................................................... 46
Assoications between Beliefs and Experiences……………………………………………. 46 Demographic Comparisons ................................................................................................... 47
V. DISCUSSION .............................................................................................................. 50
Major Findings .......................................................................................................................... 51
Environmental Benefits are the Most Compelling Reason to Support DPR ......................... 51
Drought and Support for DPR ............................................................................................... 53
De Facto Water Reuse and Support for DPR ........................................................................ 53
Climate Change and Support for IPR and DPR .................................................................... 54
Importance of Localized Data Collection ............................................................................. 56
Public and Denver Water Employee Comparisons ............................................................... 57
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Hypotheses and Results ............................................................................................................. 58
1985 and 2015 Survey Results .................................................................................................. 59
Limitations and Delimitations to the Research .......................................................................... 60
VI. CONCLUSION........................................................................................................... 62
Decades of Silence and the Impact on Water Reuse Acceptance in the Denver metro area ..... 63
Decrease in Water Reuse Acceptance ................................................................................... 63
Leverage Environmental Benefits, Drought and Climate Change Resiliency in the Denver Metro Area ............................................................................................................................ 64
Empower Denver Water Employees with Knowledge .......................................................... 66
Applicability .............................................................................................................................. 67
Future Research in the Denver metro area ............................................................................ 68
Theoretical and Additional Policy Implications ........................................................................ 69
Theoretical ............................................................................................................................. 69
Policy..................................................................................................................................... 70
REFERENCES ................................................................................................................. 71
APPENDIX ....................................................................................................................... 79
A. ADVANCED WASTEWATER TREATMENT METHODS .................................................. 79
B. COMIRB CERTIFICATE OF EXEMPTION .......................................................................... 81
C. SURVEY INSTRUMENT ........................................................................................................ 84
D. RESPONDENT COMMENTS ................................................................................................. 99
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LIST OF ABBREVIATIONS
ACT Australian Capital Territory
ACTEW Australian Capital Territory Electricity and Water Corporation, Ltd.
AWWT Advanced Wastewater Treatment
CECs Chemicals of Emerging Concern
COMIRB Colorado Multiple Institutional Review Board
CRMWD Colorado River Municipal Water District
DPR Direct Potable Reuse
IPR Indirect Potable Reuse
NPDES National Pollutant Discharge Elimination System
NPR Non-potable Reuse
TSS Total Suspended Solids
U.S. EPA U.S. Environmental Protection Agency
WHO World Health Organization
WRF WateReuse Foundation
1
CHAPTER I
INTRODUCTION AND BACKGROUND
Professor Cyrus Thomas, a noted climate scientist during the 19th century was a
leading proponent of the concept that “Rain follows the plow”. Professor Thomas once
stated,
“Since the territory of Colorado has begun to be settled, towns and
cities built up, farms cultivated, mines opened, and roads made and
travelled, there has been a gradual increase in moisture….I therefore
give it as my firm conviction that this increase is of a permanent
nature, and not periodical, and that it has commended within eight
years past, and that as population increases the moisture will
increase.” This ideal was harnessed to propagate the settlement of the American West (Reisner,
1986). Water right allocations from the Colorado River Compact Agreement were
developed and agreed upon early in the 20th century during one of the highest
precipitation periods on record. The compact regulates water allocations of the Colorado
River for seven basin states: Arizona, California, Colorado, New Mexico, Nevada, Utah
and Wyoming (Denver Water, 2014). Since the agreement was signed, the western region
of the United States has experienced a substantial challenge with managing water
resources and will continue to do so in the future. While the train of thought posed by
professor Thomas is no longer a salient belief in the American West, water continues to
be a contentious issue. Utilizing water resources efficiently is considered to be of upmost
importance, and integrating community values, needs and cultural sentiments into local
water supply management is a necessary component of water supply planning.
2
There is an urgent need to develop water supply options that meet the increasing
needs of municipalities, agriculture and industry while protecting watersheds and the
environment. As demand for water rapidly increases, the rate of aquifer depletion exceeds
the rate of replenishment. Surface water supplies are losing water to evaporation from
rising temperatures, which also results in higher evapotranspiration rates and higher
demand for irrigation water. Population growth increases demand for industrial,
municipal and agricultural purposes. The American West is the fastest growing region in
the United States. In Water 2025: Preventing Crises and Conflict in the West, the Bureau
of Reclamation claims that, “In some areas the water supply will not be adequate to meet
all demands for water even in normal years. Inevitable droughts merely magnify the
impacts of water shortages” (USBR, 2005). In a period of time when water resources are
over allocated in many parts of the world, and with the uncertainties presented by global
climate change and population growth, water reuse is a viable solution to augment fresh
water supplies.
Water reuse is the use of advanced treated municipal wastewater from homes,
businesses and industries for beneficial purposes. Beneficial uses commonly include
irrigation for parks and golf courses, industrial cooling and other processes, ground and
surface water recharge, agricultural irrigation and even drinking water. Wastewater that
is treated for reuse has traditionally been called reclaimed water or recycled water and
these terms are used interchangeably (Asano et al., 2007).
Reclaimed water use is beneficial for water providers, society and the
environment. Treating and reusing wastewater can reduce the need for or prolong the
time to develop additional freshwater supply. During drought years, reclaimed water can
3
supplant the use of freshwater, thereby preserving water in aquifers and storage
reservoirs. Water utilities can better plan for future supplies by relying on reclaimed
water as a long-term source. The use of reclaimed water for irrigation maintains
landscape appearance and property values without diminishing drinking water supplies.
When a region can supplant freshwater supplies with reclaimed water by a large volume,
aquatic ecosystems are sustained (Asano et al., 2007). Allocating water of a suitable
quality for intended beneficial uses makes the most efficient use of the world’s water
supplies.
There are three types of planned water reuse: non-potable reuse (NPR), indirect
potable reuse (IPR), and direct potable reuse (DPR). Reclaimed water for non-potable
(NPR) use is typically treated to a grade below drinking water standards, while reclaimed
water for potable purposes (IPR and DPR) undergoes advanced treatment with safeguards
to ensure public safety when ingested (Asano et al., 2007). It is important to note that
unplanned or de facto potable water reuse has been practiced since the onset of
wastewater treatment. Communities downstream of a wastewater treatment plant are
treating and drinking diluted wastewater from upstream users (Meeker, 2014).
Arid climates, drought, population growth, urbanization and regions generally
suffering from growing water supply shortages drive reclaimed water projects into
implementation (Asano et al, 2007). There are many challenges that influence whether
water reuse is a viable option to augment water supply (Bischel et al., 2012). Questions
for decision makers may include: Are the environmental, monetary and social costs of
implementing water reuse worthwhile? How will the process of reclaiming wastewater
affect upstream and downstream flows and users? Is there an urgent need to seek
4
alternatives to freshwater supplies? How will the public respond to using reclaimed water
for irrigation, agriculture, industry or potable purposes? (Dave Little, former Director of
Planning, Denver Water, personal interview October 27, 2014). The answers to these
questions have been evolving over the last half-century as reclaimed water use has
increased in many parts of the globe. Specifically with regards to public response to
water reuse applications; multiple surveys have been administered across the world in
communities that intend to implement water reuse projects. This research aims to
determine the opinion of the Denver metro area public in Colorado on various reuse
applications with an emphasis on potable water reuse and DPR.
One of the most significant contributors to water reuse implementation has been
advancement in wastewater treatment technology coupled with more stringent
wastewater effluent regulations. Under the United States Clean Water Act, the National
Pollutant Discharge Elimination System (NPDES) permit program requires that
wastewater, prior to being released into the environment to flow downstream must
undergo significant treatment processes (US EPA, 1998). Additional treatments for
reclaimed water use depend on the purpose or potential application of the reclaimed
water, and are typically more rigorous than wastewater treatment alone. Reclaimed water
treatment plants utilize multiple barriers to ensure that if one treatment method fails, one
of the other treatments will remove constituents of concern from the wastewater (Asano
et al., 2007).
The level of wastewater treatment for reuse is contextual and depends upon the
intended application, constituents in the wastewater and availability of funding for
treatment technology. Primary and secondary treatments are applied for traditional
5
wastewater treatment and thus are applied prior to reclaiming wastewater for reuse.
Primary treatment removes large objects and abrasive materials to prepare wastewater for
downstream processes. The goal is to reduce particle size and remove grit that could be
abrasive to equipment further down the treatment train. Primary treatment also removes
solids and floating materials that are easy to settle (total suspended solids or TSS).
Secondary treatment decomposes organic material and flocculates solids materials that do
not easily settle. Microorganisms convert organic matter into cell material, carbon
dioxide and water, and convert ammonia to nitrate (a process called “nitrification”) and
ultimately, into nitrogen gas (“denitrification”). Finally, pathogens, trace metals, organics
and total dissolved solids are removed or reduced in advanced or tertiary treatment.
Tertiary treatment and disinfection are not always exercised in conventional wastewater
treatment, but are commonly used for potable and non-potable reuse applications (NRC,
2012).
Advanced wastewater treatment (AWWT) is applied for potable water recycling,
with four key steps to produce high quality, purified water. The first three steps are
primary, secondary and tertiary treatment, noted above. The fourth step, advanced
treatment targets additional removal of nutrients and organic components, further reduces
total dissolved solids and salts and provides additional removal of pathogens (NRC,
2012). In some cases, the water is stabilized through restoration of alkalinity, hardness
and pH, and corrosive properties are reduced so as not to impair the piping and
distribution system. Appendix A shows a table of the various treatment methods used for
AWWT (ATSE, 2013).
6
Currently, enforceable regulations for reclaimed water do not exist at the federal
level in the United States. Due to the myriad of water reuse applications and various
requirements for water quality and technology, individual states have authority to
implement operational, water quality and reclaimed water application regulations. The
U.S. Environmental Protection Agency (U.S. EPA) has provided Guidelines for Water
Reuse that municipalities can reference which includes recommendations for water
treatment, water quality, monitoring and other considerations to protect public health.
The World Health Organization (WHO) has also developed a set of Guidelines for the
Safe Use of Wastewater, Excreta, and Greywater that are intended to provide a
framework from which nations can base decisions and regulations for water reuse (NRC,
2012).
Monetary costs for water reuse projects vary substantially because they are
contingent upon site specifics and intended application. For example, NPR systems
require dual distribution lines, storage units, treatment plants and pumping stations
whereas DPR systems use the existing municipal delivery infrastructure. The average
cost for a parallel distribution system for a non-potable system is $1.15 to $6.44 per 1,000
gallons of water, whereas a direct potable operation is $2.27 to $3.80 per 1,000 gallons of
water1 (Leverenz et al., 2011). However, DPR incurs higher water treatment costs due to
energy requirements to purify the water to drinking water standards. West Basin,
California operates non-potable and potable reclaimed water systems, with capital
1 Cubic meters converted to thousand gallons for consistency.
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reclaimed water treatment costs at $9.62/1,000 gallons/year and $28.98/1,000 gallons/
year, respectively (NRC, 2012).
Location is another factor that produces variable costs. A reclaimed water
treatment plant located at a lower elevation than its customers will incur higher pumping
and energy costs. State regulated wastewater quality affects reclaimed water treatment
costs and depends on wastewater constituents, concentration of those constituents and
pretreatment practices. Furthermore, disposal of concentrate or brine, leftover solid
material from reclaimed water treatment varies in cost depending on location and surface
water quality requirements. Coastal areas can blend concentrate with water and dispose
of it in the ocean. However, inland reclaimed water projects may not have adequate
surface waters or aquifer storage for disposal, and may require the concentrate to be
transported elsewhere, which increases costs (NRC, 2012).
The Water Reuse Foundation (WRF) has published An Economic Framework for
Evaluating the Benefits and Costs of Water Reuse to assist water agencies and
professionals with an in depth benefit-cost analysis for water reuse or desalination. This
document helps to identify, estimate and effectively communicate the internal benefits (to
the water agency) and the external or social benefits (to households, businesses,
recreationists, special interest groups, etc.), and weigh those benefits against costs
(capital, operational, environmental, social etc.) It is recommended that community and
stakeholder groups be involved in the analysis. In addition to the report, a Microsoft
Excel Workbook can be utilized to enable agencies to analyze specific information about
their water reuse project including monetary and social costs and benefits (WateReuse
Foundation, 2006).
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Non-Potable Reuse
Establishing a non-potable reclaimed water supply system is at least as complex
as developing a drinking water system. All of the requirements for a drinking water
supply system are also required in a non-potable reclaimed system. Separate,
underground distribution and piping, along with distinct pumping stations, storage
facilities and treatment plants must be constructed alongside the drinking water supply
system. In the United States, all piping and visual equipment delivering and operating
non-potable recycled water is the color purple, and is referred to as “purple pipe”. This
distinguishes between the potable and non-potable recycled supply systems. If potable
water serves as a backup supply for recycled water, contamination between the potable
and reclaimed water systems must be prevented. Planning for a non-potable reclaimed
water system must incorporate demand and supply metrics, which then affect the size of
storage facilities, underground distribution design, pumping requirements and treatment
capacity. Installing a non-potable distribution system during new construction typically
costs less than breaking ground in established, developed areas (AWWA, 1994).
A common application for non-potable reclaimed water is irrigation of edible and
non-edible crops. Agricultural irrigation accounts for approximately 40 percent of the
freshwater supply withdrawals in the United States (which can be much higher in arid
regions) (Houston, et al., 2004) and accounts for 70 percent around the world.
Substituting freshwater with reclaimed water for agricultural irrigation saves freshwater
supplies for potable purposes (Asano et al., 2007). Another benefit of agricultural
irrigation with reclaimed water is that less fertilizer may be required because non-potable
reclaimed water often contains residual nitrogen and phosphorous which are beneficial
9
nutrients for increasing crop yield and productivity (Carr et al., 2010; Jang et al., 2010).
A drawback from irrigation with non-potable reclaimed water is that salts in the water
can build up in soils and become detrimental to plant health. Soils where crops are
irrigated with reclaimed water over time show a lower salt concentration when
periodically flushed with potable water (Carr et al., 2010).
Landscape irrigation can account for anywhere from 30 to more than 70 percent
of a community’s potable water use, making reclaimed water for this purpose a viable
alternative. Irrigation of public parks, golf courses, cemeteries, schools, traffic medians
and other landscaped areas can be supplied with reclaimed water with little or no risk to
public health. Tertiary treated reclaimed water removes most of the total dissolved and
suspended solids from the water, inhibiting damage to irrigation emitters. Demand
planning forecasts for reclaimed water use must consider the seasonality of crop and
landscape irrigation in most regions, which is why non-potable reclaimed water systems
should also allocate water to year round applications in addition to irrigation purposes
(Asano et al., 2007).
Non-potable reclaimed water may be used year round in industrial applications.
Common applications include cooling towers, boiler water, rinsing, equipment cooling as
well as in manufacturing such as textile production, pulp and paper, oil refineries and
mining (Asano et al., 2004). While more stringent wastewater effluent regulations have
led to a reduction in industrial water use over the past 30 years (through conservation
technology and efficiency improvements), industrial use still makes up a significant
amount of freshwater withdrawals in the United States and around the world (Houston et
al., 2004). Water quality considerations for industrial uses focus on prevention of
10
corrosion, scaling and biofilm build up on equipment (Bell and Aranda, 2005). Tertiary
treated reclaimed water is typically appropriate for industrial purposes (Asano et al.,
2007).
Additional applications of year round reclaimed water demand year round in
urban areas include toilet and urinal flushing, fire protection, air conditioning, laundry
and car washing and public water features. Variability in all of the water quality
standards for the above mentioned uses poses the economic question as to whether it is
more cost effective to produce multiple grades of water quality to meet the needs of each
specific use, or to produce a single grade of reclaimed water that is suited for all
projected applications (Asano et al., 2007).
Indirect Potable Reuse
Indirect potable reuse involves treating wastewater and distributing it into an
environmental buffer where it filtrates and/or blends with raw water for a specific amount
of time before entering the conventional drinking water treatment plant. Environmental
buffers include lakes and reservoirs, streams and groundwater (groundwater recharge).
As mentioned previously, a multiple barrier approach is incorporated into wastewater
treatment and monitoring to remove pathogens and trace constituents to protect public
health. It is important to note that often, IPR reclaimed water quality degrades when
blended with raw surface water supplies from exposure to environmental contaminants
(Asano et al., 2007).
Groundwater injection is an IPR environmental buffer that serves multiple
beneficial purposes. When aquifers that are being depleted at a faster rate than
replenishment are injected with reclaimed water, it reduces, stops and/or reverses the
11
decline in groundwater levels. This practice also mitigates risks of land subsidence from
depleting aquifers. In coastal areas, where saltwater intrusion occurs when groundwater
levels are low, injecting reclaimed water into the underground aquifer prevents salt water
from seeping into the freshwater aquifer. Aquifers recharged with reclaimed water may
serve as water storage units during floods, and for storage of surplus reclaimed water.
Soil and substrate filter contaminants in reclaimed water, which can improve water
quality (Asano, 1985; Bouwer, 1978; Todd, 1980). Reclaimed water injected into
aquifers can be used for potable and non-potable purposes. Currently, IPR is the
prevalent potable water reuse method currently utilized in the United States and the
world. The public is often more comfortable with placing the treated wastewater into a
“natural” water body prior to entering the drinking water treatment plant and consuming
it (Asano et al., 2007).
Direct Potable Reuse
DPR is the process of treating wastewater to drinking water standards and
pumping it directly into the distribution system (pipe to pipe) and immediately served to
the public, or the purified wastewater is blended with conventionally treated freshwater in
an above ground storage basin prior to serving to the public. The major distinction
between indirect and direct potable reuse is that with direct potable reuse reclaimed water
is not placed into an environmental buffer prior to being used for potable purposes. DPR
systems meet significant potable water demand year round. As with all water reuse,
demand on freshwater supplies is reduced when replaced with high quality reclaimed
water. A substantial benefit of DPR when compared to NPR is that the reclaimed water
12
can be supplied through the existing potable water distribution infrastructure (Leverenz et
al., 2011; WateReuse Foundation, 2011).
DPR systems have some advantages over IPR. DPR does not require pumping to
an environmental buffer. Therefore, costs for delivering reclaimed water though a pipe to
the environmental buffer, and energy requirements to do so are eliminated. In IPR
scenarios, prior to adding reclaimed water to an environmental buffer, assessments on
impacts to aquatic species and habitats, public health impacts in recreational waters and
impacts on public health for consumptive users is generally required which is an added
expenditure. A comprehensive study may also be required to determine if the
environmental buffer will affect reclaimed water quality when added (ATSE, 2013).
Public acceptance is a critical component to applying reclaimed water for
drinking purposes. An account of DPR projects, public acceptance research and factors
affecting acceptance of potable reuse is assessed in Chapter 2.
13
CHAPTER II
LITERATURE REVIEW OF DIRECT POTABLE REUSE AND PUBLIC
ACCEPTANCE
There are currently few direct potable reuse systems, though popularity is
growing. Multiple organizations are conducting research and development regarding
DPR indicating that awareness of DPR as an acceptable water supply option is
increasing. The WateReuse Foundation is embarking on a $6 million research project to
explore DPR (WateReuse Foundation, 2015a). A utility survey performed by the Water
Research Foundation indicates that seven percent of utilities surveyed are considering
DPR (Water Research Foundation, 2015). The Water Environment Research Foundation
recently published a report on the challenges facing implementing DPR in the state of
Colorado with recommendations (WERF, 2015). Extreme droughts or prohibitive costs of
alternative supplies are the primary motivators for DPR. Water treatment technology,
public safety and public acceptance are the most critical issues associated to DPR, with
public acceptance being one of the most important factors for reuse project
implementation (Bruvold, Olson & Rigby, 1981).
Public acceptance and understanding public opinion of water reuse is important
for successful DPR implementation for several reasons. Reuse projects may not be
properly understood and considered by the public if information about the role the project
plays in water reliability, how the project is financed, how the project fits in with the
larger regional water supply, the impacts to water quality and the environment and health
risks are not known. Without an understanding of public concerns in the initial phase,
14
delays and costs could rise as the public’s anxieties grow and interfere with
implementation. Lastly, honesty and trust between the water agency and the public
should remain high with regards to the agency’s role and credibility to provide safe,
reliable drinking water and this cannot be accomplished without effective interaction and
communication with the public (WateReuse Foundation, 2009).
DPR Facilities in Existence
Windhoek, Nambia in Southern Africa has been treating wastewater for DPR
since 1968 (du Pisani, 2005). This region receives, on average, about 14 inches of rainfall
per year and most of the stored surface water is lost to evaporation. Windhoek’s arid
climate and population growth are what motivated the construction of the Goreangab
Water Reclamation Plant. In 2002, the plant was reconstructed and currently supplies 30
to 50 percent of the city’s drinking water (du Pisani, 2005; Lahnsteiner and Lempert,
2005). A multiple barrier treatment train including ozonation, granular and biological
activated carbon, ultrafiltration, and disinfection ensures the reclaimed water meets safe
drinking water standards (refer to Appendix A for treatment methods). Water quality
monitored through online instrumentation and samples, at each stage of treatment and
prior to delivery is constantly analyzed and held to specific standards. When any one of
these standards is not met, the plant does not deliver the reclaimed water through the
drinking water supply system, and the water is recycled back through the treatment train
until it meets the water quality criteria. Windhoek gained public acceptance for DPR
through educating the public about the state of the art treatment facility and through a
campaign regarding the grave need of consistent water supply. Windhoek has received no
15
complaints about the use or quality of reclaimed water for potable purposes (du Pisani,
2005; Lahnsteiner and Lempert, 2005).
Another DPR facility that is located in South Africa called the Beaufort West
Water Reclamation Plant has been supplying reliable, high quality reclaimed drinking
water to roughly 40,000 people since January 2011. Severe drought in 2010, reliance on
imported water and expected population growth were the main drivers for this project. In
this system, treated raw water (80%) is blended with treated reclaimed water (20%) in a
holding reservoir with both product waters complying with potable water standards. The
blended water is then distributed to the town of Beaufort West (ATSE, 2013).
In the United States, two communities in Texas have recently constructed DPR
facilities due to the prolonged and severe drought in the state. Wichita Falls, Texas fell
approximately 70 percent below its expected water supply in 2012 and 2013 due to the
drought (EBSCO Publishing, 2014). Wichita Falls already had a drinking water treatment
plant that utilized microfiltration and reverse osmosis to treat saline lake water. In order
to implement DPR, all that was needed was a $13 million 12-mile pipeline connecting the
wastewater treatment plant to the drinking water treatment facility. DPR operations began
on July 9, 2014 and the treated effluent is purified and blended with freshwater in a
holding tank at a 50/50 ratio and then treated in the conventional drinking water plant
(Dahl, 2014). A 45-day testing period was required prior to serving the water to the
public by the Texas Commission on Environmental Quality to ensure the water was safe
to drink. According to University of Texas Engineering Professor, Desmond Lawler, “If
you want to drink very clean water, direct potable reuse will likely provide higher quality
water than many drinking water plants currently produce now.” There have not been any
16
reported illnesses or diseases attributed to drinking the reclaimed water since the onset of
the DPR facility (City of Wichita Falls, 2014). Wichita Falls created a video about the
DPR project that featured utility representatives, doctors and experts from local
universities discussing the advanced water treatment process and the safety of its use for
potable purposes. The City also involved the media every step of the way to ensure the
public was informed. Daniel Nix, utilities operations manager of Wichita Falls stated
that, “Since we brought this treatment plant online, the feedback has been that the water
tastes better than the lake water we were working with before” (Martin, 2014).
A second DPR facility operating in Texas is located in the City of Big Spring.
This project began supplying drinking water to the community in May of 2013. The
system cost $14 million to construct and can supply approximately two million gallons of
highly treated reclaimed water per day (White, 2013). Public acceptance was minimal at
first, but the community is becoming more supportive2. Mayor Glenn Barham stated,
“There was probably a lot of reservations about reuse water projects when we first
discussed it in the late ’90s.” Now, with the drought, he said people have “realized we’ve
got to take steps to make our water supply stable” (White, 2013). John Grant, general
manager for the Colorado River Municipal Water District (CRMWD) claimed that there
were some concerned citizens, but once they were educated about the merits of the
project, most people were okay with it. It was the dire drought conditions that convinced
people that DPR was necessary, said Grant. Public meetings here held along with news
2 Personal phone conversation with Jennifer Posey at the Colorado River Municipal Water District, August 29, 2014.
17
releases, television coverage and radio ads. Representatives from CRMWD also attended
civic club meetings and gave presentations about the project (Martin, 2014).
The only other DPR scheme in the United States is being planned for
implementation in Cloudcroft, New Mexico. This small city of 850 residents attracts
visitors on the weekends, making the weekend population approximately 2,000 people.
Traditionally, water demands were met through groundwater aquifers and springs, but
with recent drought conditions, the city decided to implement DPR as a long-term supply
option. The treatment plant will use a multiple barrier treatment configuration, blend the
purified wastewater with spring or well water in a blending tank with a two week
detention time and send the blended water through the conventional drinking water
treatment facility before providing it to the city for potable purposes. According to the
WateReuse Foundation, public enthusiasm and backing for the project had remained high
during the onset of planning (WateReuse Foundation, 2011). A telephone conversation
with a representative from the New Mexico Environment Department on August 27,
2015 revealed that a lack of funding has prolonged implementation of the project.
Currently, regulations and operational procedures are being developed and a public
information campaign has not yet begun.
Review of Public Acceptance of Water Reuse
Success and Failure of Potable Water Reuse Implementation
Before reviewing public acceptance factors that are related to water reuse, it is
worthwhile to note other issues that impact the success of implementation of reclaimed
water projects. Aside from the motivations of drought and water shortages, recycling
wastewater reduces effluent discharges into surface or seawater, thereby helping
18
municipalities to meet water quality discharge requirements. High expenditures required
to develop water reuse infrastructure can hinder the decision to proceed with construction
and implementation (Bischel et al., 2012). Recycled water rate structures pose challenges
for decision makers, especially with non-potable reuse. Non-potable recycled water rates
tend to be less than potable drinking water rates to incentivize customers to use it, yet the
costs to construct and operate the non-potable recycled water system are similar or
greater than the costs of operating the potable system (Denver Water, 2014). Regulatory
agencies are reluctant to allow for DPR due to the lack of definitive information related
to public health protection (Dahl, 2014). High level government standardization of water
quality requirements and operating procedures for recycled water is believed to help
facilitate water reuse projects to move forward, however funding to meet those
requirements is a hindrance (Bischel et al., 2012).
Amid the financial and institutional challenges that contribute to or hinder water
recycling, public acceptance and opinion has been shown to impact water reuse project
implementation both negatively and positively (Asano et al., 2007; Burstein, 2003,
CSIRO, 2003). For example, implementation of an IPR project in Toowoomba, Australia
failed due to negative public perception of reusing wastewater for potable purposes,
despite the serious need for alternative water supplies and drought conditions. ‘Citizens
Against Drinking Sewage’, a local interest group opposed to potable water reuse,
conducted an extensive and powerful campaign that reached the public prior to the
Toowoomba Council’s campaign in favor of the reuse project. As a result, the public
voted against the project (Hurlimann & Dolnicar, 2010).
19
A similar IPR oppositional campaign resulted in failure of a groundwater recharge
IPR project in San Gabriel Valley, California. Public tours of treatment facilities,
meetings, alliance groups and education about the safety of the project were executed in
the community. However, Citizens for Clean Water, a local interest group against the
project conducted a media campaign just before the environmental review hearing for the
project. They made claims that the project was unnecessary, potentially harmful to the
public and used “Toilet to Tap” as a persuasive expression to interfere with public
support of the project. Furthermore, Miller Brewing Company was in opposition to the
project claiming it would pose environmental problems and pollute their water supply.
The project was not implemented at the time as a result of the citizen group and a lawsuit
from Miller Brewing Company (CSIRO, 2003).
Characteristics of unsuccessful potable reuse projects regarding the public have
been identified. Lack of communication about salient factors such as water quality and
health have led to failure (Burstein, 2003). Some members of the public have been
concerned that if water reuse projects are implemented, it could stimulate growth and
development by adding to the overall water supply, leading to additional effluent for
wastewater disposal. Environmental justice concerns (notably that one part of the
community will receive reclaimed water and others will not) have foundered
implementation. Insufficient public outreach and involvement and lack of consistent
public participation from beginning to end of water reuse projects have resulted in failure
to implement potable reuse (WateReuse California, 2010).
In contrast, public information campaigns executed by task forces and technical
experts for other water reuse projects in Australia, Singapore and the United States have
20
succeeded in gaining public acceptance (CSIRO, 2003; Lauer, 1993; ATSE, 2013). For
example, the Australian Capital Territory (ACT) proposed an IPR supply option in 2007
called the Water2WATER project. A thorough communication campaign was performed
by the local water utility, ACTEW Corporation (Australian Capital Territory Electricity
and Water Corporation). The goal of the consultation was to take into account as many
public views as possible while understanding the need to find a solution for the water
shortages in the community. ACTEW reached members of the community through media
advertising, public displays, community briefings and forums, mailers, surveys and a
website dedicated to the cause. The campaign was successful in gathering information
about public concern and gaining acceptance for the project (ACTEW, 2007).
In Singapore, the NEWater IPR project gained public acceptance through an
extensive public information campaign involving education, a documentary film, media,
information briefings at community centers and schools and a demonstration visitor
center. Singapore’s Public Utilities Board assured citizens that the reclaimed water
quality met WHO and U.S. EPA drinking water standards. This project is unique in that
the government distributed 1.5 million bottles of NEWater to citizens, and the media
displayed prominent government officials drinking the water. The project has been
successfully operating and supplying reclaimed water through an IPR process since 2003
(CSIRO, 2003).
Though not a potable reuse success story, the Monterey County Water Recycling
Project is worth noting. In Monterey County, California over 14 billion gallons of
recycled water is used to irrigate artichokes, lettuce, cauliflower, celery and strawberries.
This water reuse project was implemented to minimize saltwater intrusion into the
21
groundwater aquifers that have been the traditional source of irrigation water in the
region. Success is attributed to involving local growers in a five-year health study,
assuring that buyers, shippers, and other stakeholders were accepting, and that regulatory
agencies endorsed the application. The local community was in support as well, due to
educational campaigns at schools, community events, pamphlets, treatment facility tours
and exhibitions (CSIRO, 2003).
Factors Influencing Success of Potable Water Reuse Implementation
Hartley (2006) identified five major themes that aid in successful implementation
of water reuse projects by examining three case studies that aimed to contrive potable and
non-potable water recycling initiatives. Through investigation of the success and failure
of project implementation in these communities, the five major themes in gaining
acceptance and public support are as follows: (1) Managing information about science
and technology, local knowledge and site-specific characteristics (i.e. water shortage or
drought conditions) is critical to building public acceptance. Complete and transparent
facts should be delivered in a fashion that does not omit any information relevant to the
project. (2) Individual motivation and water provider organizational commitment are key
elements to public support. (3) Listening to and addressing people’s concerns has proven
to be successful in maintaining support. Developing a mutual understanding about the
needs and safety for water reuse, and continuous public dialog are essential to procure
public approval. (4) A fair and logical decision making process that involves the public
and demonstrates how the benefits and burdens are distributed evenly is vital for success.
(5) Lastly, the above-mentioned strategies help to build public trust in the entity that will
implement water reuse, which is paramount to successful water reuse projects.
22
According to Dishman et al. (1989) the first step in gaining public acceptance for
water reuse and accomplishing behavioral changes is to conduct an analysis of the
public’s wants, needs, perceptions, attitudes and habits. This information can be used to
distinguish a target audience with which additional research and/or education can be
applied to improve acceptance of water reuse. There are several critical moments in water
reuse implementation where gauging public opinion and providing information about
water reuse projects can take place. Public involvement in the initial phases of planning
helps to identify and address concerns early to avoid resistance closer to the time of
implementation. Providing educational information that is easy for the public to
understand prior to inquiring about concerns is recommended (Asano et al., 2007; CSIRO
2003). Involving the public after technical experts have weighed the options and
communicated their preferred solution allows for all vital information about the posed
solution to be presented. However, because one option is presented to the public, this
level of engagement can be viewed as technocratic. Providing multiple options for the
public to decide upon in a straightforward manner is more transparent and allows for
input on multiple options prior to final implementation (Recycled Water Taskforce,
2003).
The best strategy for successfully implementing water reuse is to involve the
community prior to the conception of the project. This is the most essential building
block for obtaining long-term public acceptance. The public should understand the
various supply options (i.e. new reservoir vs. water reuse project), including the
advantages, disadvantages and triple bottom line costs of each solution. Information
should not be designed to persuade the public, but rather to clarify perceived risks by
23
explaining wastewater treatment technology through examples of successful potable
reuse projects (CSIRO, 2003).
Survey Findings on Public Perception of Water Reuse
Multiple public opinion surveys have been conducted over the past several
decades that reveal specific public concerns regarding water reuse. Until the early 1970’s,
public opinion had not been systematically assessed with regards to acceptance levels and
reclaimed water. General attributes regarding acceptance are that individuals with a
higher level of education and who have some knowledge about water reuse are more
accepting. Males are slightly more accepting than females, and individuals under the age
of 50 are more accepting. When people perceive the current water supply as inadequate
to meet future demand, acceptance for potable reuse increases. Trust in water treatment
technology correlates with higher levels of acceptance. Individuals are more comfortable
with recycled water uses that do not involve physical contact with their bodies. For
example, recycled water for landscape irrigation is generally more acceptable than
bathing or cooking with recycled water (Bruvold, 1971 & 1998; Baumann, 1983). These
correlations have not deviated much over time, however more recent surveys have found
additional influences that lead to support and opposition to potable water reuse.
Studies reveal that public opposition to potable water reuse is due to the “yuck
factor”; that citizens are inimical to drinking treated sewage water. A survey conducted in
Australia concluded that the perception of potable reuse as “filthy and unclean” was the
main reason for rejecting the reuse system. Recycled water, in an individual’s mind, may
be associated with disgust through the law of contagion, which suggests that a neutral
object may acquire disgusting properties from another object through brief contact. Thus,
24
recycled water having been in previous contact with human wastes is what contributes to
the “yuck factor” and thus the desire not to drink or support potable reuse (CSIRO,
2003).
Perceived risk with respect to drinking reclaimed water is another deterrent for
public acceptance. Concerns about the potential adverse health effects of drinking or
using recycled water are commonly attributed to lack of water reuse support. Uncertainty,
fear, catastrophic potential, controllability and equity encompass perceived risk for the
public (CSIRO, 2003). The WateReuse Foundation recommends that multi-barrier
treatment, treatment that provides more than the minimum requirements for public health
protection, and demonstration of process reliability (consistent delivery of safe water)
help to alleviate risk perception (WateReuse Foundation, 2014b).
Recent studies have authenticated that direct human contact with reclaimed water
is inversely associated with acceptance. For example, irrigation of golf courses, parks,
and crop irrigation with reclaimed water show less opposition when compared to
residential toilet flushing, bathing, cooking or drinking (CSIRO, 2003; Asano et al.,
2007; Hartley, 2006; Friedler, et al., 2006).
The source of reclaimed water affects public acceptance. Some studies found that
reuse of individual household or neighborhood greywater is preferred due to perceptions
of control, and distrust in the consistency of reclaimed water quality delivered by the
water provider. Furthermore, individuals were more comfortable with reusing their own
wastes rather than citywide wastewater (CSIRO, 2003; Hartley, 2006). Other studies
suggest the opposite: individuals do not trust themselves to control water quality, and
having more greywater systems in operation could increase the probability of water
25
treatment failure. Thus, citywide wastewater reuse was preferred by survey participants
(CSIRO, 2003).
It is evident that an understanding of the upstream-downstream context of urban
water recycling positively influences acceptance of drinking reclaimed water. Visual
representations of unplanned potable reuse coupled with positive terminology (i.e.
‘purified water’ vs. ‘reclaimed wastewater’) leads to a general understanding that much
of the water we currently drink has been used upstream prior to treatment, and
technology is available to treat water to a safe and high quality for potable use
(WateReuse Foundation, 2013).
There is strong evidence demonstrating that public trust in the institutions
responsible for water project design and operation affects acceptance levels for potable
reuse. Focus group participants in a study with the Water Corporation of Western
Australia listed trust in the Water Corporation as the main reason they would be willing
to use recycled water. Long term dependability and the perception that the Corporation is
not politically or monetarily driven are main reasons participants feel they can trust the
Corporation to provide safe recycled water (CSIRO, 2003). Additionally, a survey
conducted in Tucson, Arizona indicated that the public trusted academic researchers and
the water utility most with respect to providing accurate information about reclaimed
water, and distrusted local elected officials and the media (Ormerod and Scott, 2012).
Environmental and environmental justice concerns affect public acceptance of
water reuse. Individuals that are generally concerned about natural resources and
conservation are more apt to support water reuse (Rock et al., 2012). Furthermore,
perceived unfairness and inequality regarding the safety of water being delivered to high
26
and less affluent communities can lead to public opposition. It is important that the public
understand that recycled water is not targeted towards less affluent communities (CSIRO,
2003). A public information campaign for IPR in San Diego, California was gaining
positive momentum and public support until concerns were raised about racial and
economic bias associated with the project design (Hartley, 2006).
Experience with water shortages and watering restrictions is associated with
acceptance. Messages that emphasize the reality of water scarcity, specifically to the
geographic region in which reuse is an alternative have been shown to increase the
likelihood of favoring a potable reuse option (Dolnicar et al., 2011). Furthermore, many
people view that recycling water is an environmentally responsible thing to do (Water
Reuse California, 2010).
Chemicals of emerging concern (CECs) pose additional challenges to public
acceptance of potable water recycling. These chemicals are added to surface water,
wastewater, and groundwater from pharmaceuticals, health care products, and other
constituents from household, commercial, and industrial water use. There is still
significant need to understand the health and environmental effects of these chemicals in
waterways. Due to the uncertainty about these effects, a sound public communication
strategy regarding CECs needs to be researched and addressed. Based on research in
other industries facing public opposition and communication challenges, the Water
Environment Research Foundation suggests communicating risk in the face of
uncertainty, building trust with the public, conducting public surveys to determine
concerns prior to a public information campaign, emphasizing benefits of water reuse,
involving the public in decision-making processes, and recognizing the role and
27
implications of stigma as tools to effectively communicate about CECs (Water Reuse
California, 2010). It is important to note that CECs have been reported in United States
drinking water from unplanned indirect potable reuse. Conventional water and
wastewater treatment technology often do not remove all of these constituents and they
remain in the water after drinking water treatment and wastewater treatment (ATSE,
2013).
One of the most recent public acceptance surveys was conducted on residents of
San Diego and Santa Clary County, California in June of 2014. The study had five focal
points: 1) context for attitudes on water issues, 2) perceptions of recycled water, 3) initial
attitudes toward potable reuse, 4) identifying persuadable information, and 5) impact of
messaging (WateReuse Foundation, 2015b). This research was motivated by the current
drought in California whereby the Governor of California declared a drought State of
Emergency in January of 2014 (State of California, 2014). The study found that most
residents are concerned about the drought, consider it a severe crisis and have a positive
attitude towards their water provider (WateReuse Foundation, 2014c).
Results from the study regarding perception of recycled water were consistent
with previous acceptance research. Familiarity of recycled water increased with
education and knowledge of water reuse, and these variables increased level of
acceptance. Men were generally more accepting of potable reuse than women, and
support for DPR declined with increasing age. Potable water reuse applications were
viewed less favorably than non-potable use. While most residents were confident that it is
possible to treat reclaimed water to drinking water standards, those residents were still
not receptive to the idea of potable reuse (WateReuse Foundation, 2014c).
28
Definitions of IPR and DPR were provided to participants. The majority of
participants supported IPR, but were less supportive of DPR. Republicans were less
supportive than democrats or independents. White Americans were more supportive than
other ethnic groups. People who stated that they drink unfiltered tap water were more
accepting of DPR. Desire for the need to expand water supply was the primary
motivation for DPR supporters. Fear of the efficacy of the treatment system and safety
concerns were large impediments to acceptance of DPR. Information about safety of
DPR swayed some of the initial opponents to support DPR after messaging (WateReuse
Foundation, 2014c).
This study and others demonstrated that the use of a term other than ‘recycled
water’ or ‘reclaimed water’ was preferred by survey participants. The use of the terms
‘purified water’ or ‘advanced purified water’ were most popular. When a general
description of the treatment process of DPR was provided, favorability increased.
Overall, the more information that was provided about DPR, the more confidence it
instilled in participants. Posing water recycling as a positive impact for the environment
resonated strongly (Rock et al., 2012; WateReuse Foundation, 2014c).
Results from public perception research on water reuse reveal key points for water
providers seeking to improve public acceptance of DPR. While some of the associations
to acceptance remain unchanged from previous research, it is important to remain up to
date on factors that contribute to support and opposition, especially as water supply
conditions and DPR treatment technology change. In a consultation with industry
professionals at the forefront of planning potable reuse, the most agreed upon
recommendation is to maintain a current understanding of public opinion to determine if
29
there has been a change in acceptance of recycled water for drinking, and the measures
that would build confidence in the DPR process for the public (WaterReuse California,
2010).
Context of Research
Colorado is the seventh fastest growing state in the U.S. (Brennan, 2012) where
water is a contentious issue due to the distribution of water relative to the population.
Approximately 80 percent of the water in Colorado is located on the West Slope (the
west side of the continental divide) while about 80 percent of the population resides on
the East Slope (the east side of the continental divide). Denver Water, the public water
utility responsible for supplying treated water to approximately 1.3 million metropolitan
customers diverts water from the West Slope and the East Slope to meet municipal water
demand (Denver Water, 2014). According to the Denver Regional Council for
Governments, the population that Denver Water will be serving by the year 2050 is
approximately 1.9 million customers (Denver Water, 2002).
Denver Water’s ability to provide long-term, reliable supplies for its customers
rests on three strategies for augmenting existing supplies: conservation, developing new
supplies, and water reuse. Denver Water’s Conservation Section provides multiple
programs for all customer types that include rebates and installations of high efficiency
water fixtures, landscape change incentives (to plant types that require less irrigation
water) and conservation programs for industrial and commercial customers. These
programs build rapport between the West Slope and East Slope as metropolitan residents
work toward using the state’s water resources as efficiently as possible. Developing new
supplies entails reservoir expansion, more freshwater diversions, capital investments in
30
dams, environmental impact reviews and acquiring water rights. Currently, Denver Water
is working to expand one of its largest reservoirs (Gross Reservoir) on the East Slope to
meet additional demands for build out of its service area in 2045. According to Denver
Water’s 2002 Integrated Resource Plan, at build out, demand for water will increase by
100,000 acre-feet compared to year 2002 demand, and the Gross Reservoir expansion is
necessary to help meet this projected demand (Denver Water, 2002).
The Denver Water Board of Commissioners recognizes that water reuse is a
beneficial and viable augmentation solution. Denver Water’s non-potable recycled water
treatment plant has the capacity to supply five billion gallons annually at build out. This
water irrigates golf courses and parks, is used as cooling water for Xcel Energy’s
Cherokee electric facility and other non-potable purposes (Denver Water, 2014). Denver
Water is authorized to reuse water that is diverted from the Colorado River basin through
court rulings from the early 1900’s and subsequent rulings in the 1970’s (NRC, 2012).
The logic behind these rulings is that water from the West Slope that is transferred and
used on the East Slope remains on the eastern side of the continental divide once used,
and therefore can be reused to extinction.
Potable water reuse is not a foreign concept for Denver Water. During the 1980’s
and 90’s, the Denver Potable Water Reuse Demonstration Project took place at the
direction from the Board of Denver Water Commissioners. The Project remains
unprecedented in its scope. Extensive water quality data were collected over a ten-year
period for four treatment configurations of wastewater effluent from the Denver
Metropolitan Wastewater Reclamation District. Treatment trains were analyzed for not
only water quality, but also cost effectiveness and reliability. Upon reaching consensus
31
on the treatment process that met all above-mentioned criteria (which also met EPA
drinking water standards), a two-year health effects study was completed on rats and
mice. No toxicological, carcinogenic or reproductive adverse health effects were
observed. Furthermore, inflation adjusted operation and maintenance costs, full-scale
plant development and treatment costs of a DPR project were discovered to be
comparable to conventional water supply development strategies at the time (Lauer,
1993; Condie, 1994).
A public information campaign coincided with the evolution of the demonstration
project. Multiple types of information about the project and DPR were provided: water
bill stuffers, newsletters, media outlets and a documentary reached over 50,000 Denver
area residents. Escorted audio-visual tours of the demonstration plant were offered, which
attracted over 7,000 visitors, representing local residents and international visitors from
more than 40 countries across six continents. Technical presentations were given at
conferences and meetings around the world in an effort to gain credibility and regulatory
agency acceptance (Lauer, 1993).
Concurrently, the Denver Research Institute conducted a series of public opinion
surveys regarding acceptance of water reuse, specifically for drinking purposes. In 1982,
Denver resident survey participants were equally divided with regards to acceptance of
drinking highly treated wastewater: 33.1% minded a lot, 31.3% minded a little, and
33.1% did not mind (4.5% did not know). In 1985, the same survey was conducted on a
different representative sample of Denver residents and results had changed (though not
statistically significantly): 23.8% minded a lot, 45% minded a little, and 27% did not
mind (4.2% did not know). This shows that the level of uncertainty around drinking
32
reclaimed water had grown in three years. As a result, 71 members of the 1982 and 1985
respondent groups were asked to participate in further research to discover how various
modes of education affect acceptance of drinking reclaimed water. A guided tour of the
Denver demonstration treatment facility increased acceptance more than information
from a brochure. Participants who participated in the tour and whose position changed to
favor acceptance initially had the most negative views of drinking reclaimed water in
1982 (Lohman, 1989).
The survey results, at the time, coincided with other studies taking place in the
United States. People opposed to water reuse had received fewer years of education, had
lower occupation and income levels, were typically older, more likely to be female, and
had little knowledge or awareness about water reuse. Results of the Denver study were
presented at the 1987 Water Reuse Symposium to a broad range of water professionals
including system managers, consulting engineers, hydrologists, government water
program managers, planners, policy makers, biologists, chemists, geologists, economists
and lawyers. During the symposium, professionals were asked about their acceptance
levels for various types of water reuse and in every type, they were less accepting than
the general public. In 1988, approximately 170 water professionals took the same survey
that Denver residents responded to in 1982 and 1985, and 58% of the professionals
opposed drinking reclaimed water compared to 27% of Denver residents (Lohman,
1987).
The most recent detailed public opinion survey regarding DPR in the Denver area
was completed and published nearly 30 years ago (Lohman, 1987). The Colorado Water
Conservation Board states in Colorado’s Water Plan (in draft) that tracking public
33
attitudes through baseline and ongoing surveys with regards to water reuse is a potential
action that should be carried out to meet the minimum water demands of the future
(CWCB, 2014). Due to the pervasive recommendation from water reuse experts to update
public opinion surveys, determine if there have been any significant changes in opinion
and/or correlate determinants of acceptance, and the fact that this information is
necessary to understand the essential concerns that need to be addressed to implement
DPR, a public opinion survey was conducted in the summer of 2015 in the Denver metro
area.
The public survey served multiple purposes. First, it conveyed associations
between acceptance of potable water reuse and other factors, including knowledge of and
agreement with local water supply issues. Experience with drought, demographics and
length of residency in the Denver metro area were assessed for associations to reuse
applications. Secondly, six statements about DPR were provided to determine if the
statements were convincing reasons to support DPR. Third, results of the survey were
compared to the Denver Research Institute’s survey from 1985 to determine if any
changes in acceptance have occurred over the past 30 years. Lastly, Denver Water
employees were asked a series of questions from the residential survey to compare results
of acceptance between water industry professionals and the general public.
It was expected that the results of the survey would reflect those found in the
literature. Men would be more supportive of potable reuse than women and
white/Caucasians would be more supportive than other ethnic groups. A negative
correlation between age and potable reuse support was expected. The following attributes
were expected to correlate positively to support for potable reuse: higher education
34
attainment and income, longer duration of residency in the Denver metro area, belief that
drought and climate change will impact future water supplies and familiarity with water
recycling. Also, it was expected that individuals would be more comfortable with water
reuse applications that do not involve as much human contact (i.e. landscape irrigation vs.
cooking). Support for IPR was anticipated to be stronger than support for DPR.
Exploratory results were also reported, specifically with regards to the six DPR
statements and whether or not the Denver public found the statements to be a convincing
reason to support DPR.
35
CHAPTER III
METHODOLOGY
An online platform was used to collect responses to the questionnaire through
SurveyMonkey, Inc., a leading provider of web-based survey solutions. SurveyMonkey
provides tools for companies and researchers to develop questionnaires and organize and
analyze responses. SurveyMonkey offers non-cash incentives to respondents in an effort
to encourage participants to provide honest and thoughtful opinions. After responding to
a survey, respondents are provided the option to donate a nominal amount of money to
the charity of their choice, and they are entered for a chance to win a sweepstakes prize.
Subjects
Denver Metro Area Public
Individuals residing in the Denver metro area completed the questionnaire.
Denver Water provided a list of zip codes to the researcher and the list was provided to
SurveyMonkey to assess the number of completed responses that could be expected.
SurveyMonkey determined with confidence that they could acquire 300 completed
responses from individuals residing in the regions of the zip codes provided.
SurveyMonkey ensures that the panel of survey participants is representative of
the general population by executing periodic benchmarks on information entered by
participants in their online profiles. Participants agree to take surveys with
SurveyMonkey are required to enter information about their income, employment,
demographic information and other target criteria, which enables SurveyMonkey to
36
deliver surveys to specific audiences for various purposes. While SurveyMonkey can
administer surveys to specific audiences, they ensure that the sample frame is not biased
based this information. Individuals who reside in the zip codes to which Denver Water
supplies water were notified via email that a survey pertaining to their profile criteria was
available to complete. Additionally, an alert was placed on the individual’s online
SurveyMonkey account page that notified them of the available survey.
Denver Water Employees
Several of the questions from the survey were sent to water utility professionals at
Denver Water including employees that work in finance, information technology, water
quality, water supply planning, public affairs, legal, customer care, underground
distribution and engineering. A link to the questions was posted in the online newsletter
that is received by all Denver Water employees with a brief description of the purpose of
the research. The public and Denver Water research protocols were approved by the
Colorado Multiple Institutional Review Board (COMIRB) and the Certificate of
Exemption is located in Appendix B.
Instrumentation
An online survey platform powered by SurveyMonkey was used to generate the
questionnaire and collect results. The researcher developed and created the questions
delivered by the web-based platform. Multiple questions utilized in the survey were
extrapolated from research was conducted in Santa Clara and San Diego in June of 2014
published by the WateReuse Research Foundation (WateReuse Foundation, 2015). The
Denver survey contained approximately 20 questions, and there was an open ended
37
optional comment section at the end of the questionnaire. A copy of the questionnaire is
provided in Appendix C.
The survey instrument was provided to the researcher’s friends, family, professors
and colleagues to test the questions prior to administering it to the public. Those who
tested the survey were asked to comment on confusing or misleading content and format
in the questionnaire. Fifteen pretests were completed and appropriate edits were made to
the questionnaire.
Content
The administered survey instrument contained seven sections. Section one
assessed the respondents region of origin and whether the respondent had lived in a
region where drought conditions caused their local water utility to mandate or expect
water use reductions. The second section collected data on level of knowledge regarding
recycled water, and asked whether Denver Water supplies recycled water in the
community. Section three assessed the respondents’ comfort level, using a Semantic
Differential Scale3, with potable and non-potable uses of recycled water. Section four
3 A semantic differential scale is a questionnaire format in which the respondent is asked
to rate something in terms of two opposite adjectives (e.g., rate comfort level with water
reuse applications), using qualifiers such as “uncomfortable”, “somewhat uncomfortable”
to “somewhat comfortable, and “comfortable” to bridge the distance between the two
opposites (Babbie, 2013).
38
provided definitions of IPR and DPR and utilized a Likert scale4 to determine the level of
support for each potable reuse application. This section also asked respondents to rank, in
order of preference, water supply options for the Denver metro area including
construction or expansion of dams and reservoirs, IPR and DPR. Section five used a
Likert scale to assess the level of agreement with three statements about water
management in the Denver area about climate change, drought and recycled water being
a form of mitigation to water supply shortages. Section six provided six statements about
DPR and asked the respondents to indicate whether or not the statement was considered a
convincing reason to support DPR. Lastly, demographic information was collected on
gender, age, race, income and education. An optional commentary section was provided
at the end of the survey.
Design
Online surveys reduce data collection time, allow for flexible questionnaire
format, facilitate data export and can be lower in cost compared to mail and telephone
surveys. However, online surveys also have limitations. Individuals who do not have
access to a computer and the Internet, or those who simply do not use these technologies
often are not able or willing to respond to the survey. This can compromise the
generalizability of the survey results (Granello and Wheaton, 2004). In order to avoid this
type of bias, a mixed method of mail, web-based and telephone surveys can be utilized;
4 A Likert scale uses response categories such as “strongly support”, “support”, “oppose”
and “strongly oppose” to assess respondents’ level of intensity in agreement or support of
a given survey item (Babbie, 2013).
39
however this was not economically feasible for this research. Telephone surveys require
trained individuals to make multiple phone calls which incurs costs, and mailed surveys
require postage payment and often yield low return rates (Babbie, 2013). Given the
challenges of these other forms of survey research, the online format was chosen to
administer these surveys.
Questionnaires must be constructed in a manner that ensures optimal participation
and there are multiple techniques that can be utilized in developing the questionnaire that
encourage successful survey research. The first several questions posed in a survey
should be simple; if the first set of questions delve into technical inquiries with long
winded statements to read, the participant may lose interest. Furthermore, demographic
information should not be collected until the end of the survey. Respondents are reluctant
to offer personal information before understanding more about the research (Babbie,
2013). The questionnaire in this research was developed to flow from simple to more
technical questions with demographic questions at the end.
Survey question format and wording are other important factors that can impact
participation. Questions must be articulated clearly for the reader and must be easy to
understand. Definitions may need to be provided in the cover letter and within the
questionnaire itself to ensure respondents understand questions and can answer them to
the best of their ability. Furthermore, the format should easily lead the reader from one
question to the next and not cause confusion (Babbie, 2013). One advantage of utilizing
an online survey platform is that researchers may put each question on a new page to
avoid confusion. Also, researchers may choose to not allow respondents to hit the “back”
button to change answers to preceding questions.
40
Lastly, survey questions must be constructed in a manner that does not convey
bias in the mind of the reader. In other words, the questions must not reflect the opinion
of the researcher and should not offer information within questions that would influence
the reader to choose one response over another. However in this research, the section that
provided six statements about DPR and asked whether the information would be a
convincing reason to support DPR is an exception to this rule. The goal of this section of
the survey was to determine if the information provided would influence opinions.
Data Analysis
IBM Statistical Package for the Social Sciences (SPSS) Grad Pack Version 23
was utilized to analyze the results of the questionnaire. Questions posed in the survey
reflect public opinion and therefore, SPSS is an appropriate tool for assessing the
information collected. SurveyMonkey enables researchers to export survey results in
multiple formats, including the .sav format that works well with the SPSS software.
While SurveyMonkey account holders have the ability to compute a detailed level of
analysis on survey results, the researcher utilized SPSS to enable more complex statistical
analyses.
41
CHAPTER IV
RESULTS
Descriptive Statistics
Demographic Attributes
Three hundred and thirteen individuals residing in the Denver metro area
responded to the questionnaire (n=313) within one week of notifying potential
participants. The majority of respondents were White/Caucasian (White/Caucasian:
80.5%, Hispanic/Latino: 9.3%, African American: 4.5%, Asian/Pacific Islander: 3.2%,
Native American: 1%, other: 1.6%). Additionally, most of the respondents were female
(Female: 63.6%, Male: 36.4%). Percentage of the public respondents’ age, income,
education and length of residency in Denver are presented in Tables 4.1a through 4.1d.
One hundred and thirty-nine Denver Water employees (approximately 13% of
total employees) responded to four of the questions that were presented in the survey
administered to the Denver metro area public. The questions that were provided to
Denver Water employees addressed 1) various comfort levels with water recycling
applications, 2) support for IPR, 3) support for DPR and 4) agreement with three
statements about climate change, drought and water supply issues.
Table 4.1a: Percentage of respondents’ age
Age
Under 18 18-29 30-39 40-49 50-64 65-75
76 or above
Percent 0 22 26 14 23 12 3
42
Table 4.1b: Percentage of respondents’ income
Income $25,000 or less
$25,001-$50,000
$50,001-$75,000
$75,001-$100,000
$100,001 or more
Percent 14 27 20 15 24
Table 4.1c: Percentage of respondents’ education attainment
Education
General Education
Development
High School
Diploma
Bachelor's Degree
Master's Degree
Doctoral Degree
Technical or
Vocational Degree
Other
Percent 2 24 36 19 3 10 6
Table 4.1d: Percentage of respondents’ length of residency in
Denver metro area
Length of residency
Less than 3 years
3-9 years 10-14 years
15-24 years
25 years or more
Percent 13 15 7 20 45
Other Respondent Characteristics
Respondents were asked multiple questions regarding drought, climate change
and familiarity with recycled water and recycled water use. Tables 4.2 and 4.3 display
agreement with various statements related to water topics for the public and Denver
Water employees, respectively. Table 4.4 compares public response to Denver Water
employee responses to comfort levels with various water recycling applications,
including results from the previous survey conducted on the Denver public in 1985.
Table 4.2: Percent of respondents’ opinions and knowledge of water-related topics
in the Denver metro area
Survey Item Percent
Have experienced drought 72
Believe they are familiar or very familiar with the concept of recycled water 79
43
Table 4.2: cont.
Survey Item Percent
Believe that Denver Water supplies recycled water in the community 27 Agree or strongly agree that climate change will impact water supplies for the Denver metro area 81 Agree or strongly agree that the Denver metro area could experience a severe drought in the foreseeable future 79 Agree or strongly agree that the use of recycled water for drinking water could alleviate water supply pressures in the Denver metro area 74
Table 4.3: Percent of Denver Water employees that agree with water-related
topics
Survey Item Percent
Agree or strongly agree that climate change will impact water supplies for the Denver metro area 83 Agree or strongly agree that the Denver metro area could experience a severe drought in the foreseeable future 93 Agree or strongly agree that the use of recycled water for drinking water could alleviate water supply pressures in the Denver metro area 80
Table 4.4: Percent of public respondents and Denver Water employee respondents
who feel comfortable or somewhat comfortable with various water recycling
applications
Reuse Application Public 2015 Public
1985* DW Employees
Landscape Irrigation 89 98 97
Industrial Use 87 NA 99
Toilet Flushing 84 95 92
Edible Crop Irrigation 75 90 81
Bathing 43 60 49
Laundry 60 68 65
Cooking 34 39 42
Drinking 30 72 38
*Lohman & Milliken, 1985
44
Water Supply Ranks
Respondents were asked to rank four water supply options for the Denver metro
area, which included 1) build a new dam/reservoir, 2) expand an existing dam/reservoir,
3) IPR and 4) DPR. A rank of 1 indicated the least preferred supply option and a rank of
4 indicated the most preferred supply option. The average response value was calculated
on the ratings and shows that the sample of respondents were fairly equally divided with
regards to preferred supply options. Table 4.5 lists the averages for each water supply
option.
Table 4.5: Average response values for preferred water supply options for the
Denver metro area
Water Supply Option Average
New Dam/Reservoir 2.60
Expand Existing Dam/Reservoir 2.62
IPR 2.25
DPR 2.53
Support for IPR, DPR and Statements Regarding DPR
Overall, 48% of the respondents somewhat or strongly support DPR while 72% of
the respondents somewhat or strongly support IPR. Table 4.6 shows the percent of
respondents who found the six statements about DPR to be somewhat or very convincing
as a reason to support DPR.
45
Table 4.6: Percent who consider information about DPR to be somewhat or very
convincing to support DPR
Statement
Very or
somewhat
convincing
Very
convincing
1. The water purification process for direct potable reuse uses state-of-the-art multi-stage technology and monitoring. It cleans water to a very high standard and ensures that drinking water produced is safe and free of harmful chemicals and toxins. Water quality monitoring occurs at each stage of treatment and prior to delivery to the public. 87 32 2. The following communities have implemented direct potable reuse to supply drinking water to homes and businesses: Big Spring, Texas (2 years) and Wichita Falls, Texas (1 year) and Windhoek, Nambia in Africa (35 years). To date, there have been no reports of negative health impacts from direct use of recycled water in these communities. 81 32 3. Denver Water completed a ten-year pilot project that experimented various water treatment technologies for direct use of recycled water in the 1980’s. During the project, scientists and engineers determined that it is possible to treat wastewater to drinking water quality and provide it to the public with little to no risk to public health. The water was tested on laboratory rats and mice (rats and mice have similar physiological, neurological, and genetic traits as humans) for two years and no negative health impacts were reported in the laboratory animals. The recycled water was of the same water quality as Denver Water’s drinking water at the time. 82 29 4. The amount of fresh water on the planet does not change. Through nature, all water has been used and reused since the beginning of time across every river system in the world. Using advanced technology to purify recycled water merely speeds up a natural process—and in fact, the water produced through advanced purification meets a much higher standard of quality than what occurs naturally. 85 39 5. Using recycled water is good for our environment. The more recycled water we use, the less we have to take out of rivers, streams and reservoirs. That’s good for rivers, streams, and the fish, plants and wildlife that rely on them. 88 50 6. Recycling water is a highly drought-resistant way to help ensure a reliable supply of water to meet local needs, independent of climate change or weather. 90 40
46
Analyses
Associations between Beliefs and Experiences
Person product moment correlation coefficient (Pearson’s r) was calculated for
variables expected to have a positive or negative association. Statistical significance is
defined as p ≤ 0.05 for all tests, and a weak correlation corresponds to a value close to
zero while a strong correlation corresponds to a value of one. There was no statistically
significant association between IPR or DPR and level of education, length of residence in
Denver or age. However, many of the hypothesized associations proved to be statistically
significant. Respondents with (1) experience living with drought, (2) who believed in
reality of climate change, (3) who were familiar with recycled water and (4) who
understood that recycled water could alleviate supply issues were more likely to support
IPR or DPR. The Pearson’s r coefficients are listed in Table 4.7.
Table 4.7: Associations between beliefs and experience and support for IPR and
DPR
Belief or Experience Support for IPR Support for DPR
The Denver metro area could experience a severe drought in the foreseeable future.
0.23 (p = 0.01) 0.21 (p = 0.01)
Climate change will impact water supplies for the Denver Metro Area.
0.15 (p = 0.01) 0.19 (p = 0.01)
How familiar do you consider yourself with the concept of recycled or reclaimed water?
0.30 (p = 0.01) 0.31 (p = 0.01)
The use of recycled water for drinking water could alleviate water supply pressures in the Denver metro area.
0.42 (p = 0.01) 0.44 (p = 0.01)
47
Demographic Comparisons
Independent t-tests were calculated for demographic variables to determine
differences of opinions regarding potable reuse topics. Statistical significance is defined
as p ≤ 0.05, meaning there is a five percent chance that the difference between the two
groups is from chance alone. Tables 4.8, 4.9 and 4.10 show results of t-tests performed
for demographic variables. Table 4.11 shows the difference between support for IPR and
DPR. The mean is the average response, the standard deviation is the extent to which the
groups tested vary in response. Standard deviation values that are closer to zero indicate
that the data points are closer to the mean and are not spread out amongst a normal
distribution curve. The Confidence Interval indicates that with 95% confidence, the
values for responses will vary between the two data points listed.
Table 4.8: Opinions and comfort levels amongst males and females
Differences between male (n = 114) and female (n = 199)
Gender Mean SD p
Confidence
Interval
Support for DPR Male 2.61 0.91 0.01 0.05 to 0.5 Female 2.34 0.93
Comfort with edible crop irrigation Male 4.17 1.14 < 0.01 0.09 to 0.66
Female 3.80 1.29 Comfort with cooking Male 2.76 1.59 0.04 0.01 to 0.72
Female 2.39 1.51 Comfort with drinking Male 2.65 1.57 0.01 0.09 to 0.80
Female 2.20 1.45 DPR De Facto water reuse statement Male 2.35 0.69 0.02 0.01 to 0.34
Female 2.17 0.69
48
Table 4.9: Opinions and comfort levels amongst white/Caucasians and non-white
ethnicities
Differences between white/Caucasian (n = 252) and non-white (n = 56)
Race Mean SD p
Confidence
Interval
Comfort with cooking White/Caucasian 2.45 1.5 0.05 -0.97 to 0.01
Non-White/Caucasian 2.93 1.7
Comfort with industrial use
White/Caucasian 2.58 1.22 0.01 -0.86 to -0.03
Non-White/Caucasian 3.03 1.43
Comfort with toilet flushing
White/Caucasian 4.46 1.05 0.01 0.11 to 0.94
Non-White/Caucasian 3.92 1.48
DPR purification statement
White/Caucasian 2.23 0.63 0.02 0.02 to 0.40
Non-White/Caucasian 2.01 0.67
DPR De Facto water reuse statement
White/Caucasian 2.28 0.69 < 0.01 0.07 to 0.47
Non-White/Caucasian 2.01 0.67
Table 4.10: Support for IPR and DPR amongst Denver Water employees and
Denver public (Somewhat and strongly support combined)
Differences between Denver Water employees (n = 139) and Denver
public (n = 313)
Respondent Mean SD p
Confidence
Interval
Support for IPR DW Employees 1.85 0.45 < 0.01 -0.21 to -0.05
Public 1.72 0.93
Support for DPR DW Employees 1.65 0.47 <0.01 -0.26 to -0.07
Public 1.48 0.50
Table 4.11: Comparison of public support for IPR and DPR (Somewhat and
strongly support combined) Public support for IPR compared to Support for
DPR
Mean SD p Confidence Interval
Support for IPR 1.72 0.44 < 0.01 0.16 to 0.31 Support for DPR 1.45 0.50
These tables show the difference between means for various comfort levels and
support for water reuse applications. The response scale for tables 4.8 and 4.9 was 1 to 5,
49
with 5 being “comfortable” and 1 being “uncomfortable”. The scale for response to
support for IPR and DPR in Tables 4.10 and 4.11 was 1 through 4, with 4 representing
strong support and 1 representing strong opposition. Table 4.8 shows that men were more
supportive than women for each of the water reuse applications and statements listed.
Table 4.9 shows that non-white/Caucasians were more comfortable with cooking and
industrial reuse applications, white/Caucasians were more comfortable with toilet
flushing and white/Caucasians found the DPR statements regarding the water purification
process and de facto water reuse more convincing than non-white/Caucasians. Table 4.10
indicates that Denver Water employees are more supportive of IPR and DPR than the
public. Lastly, Table 4.11 shows that the public is more supportive of IPR than DPR.
50
CHAPTER V
DISCUSSION
Water supply management is one of the largest challenges facing the world today.
Climate change could impact precipitation patterns and evaporation of surface water
supplies while droughts could become more severe and/or more frequent (IPCC, 2007).
The ever growing population and relocation of people into arid regions adds additional
stress to water supplies. Alternative water management practices and water augmentation
plans will be necessary to sustain water supplies into the future. Water reuse is a viable
option to maximize efficiency and use of water supplies, especially at the local level.
However utilities that wish to implement water reuse, specifically potable water reuse
have more success when they engage with the public in advance to understand and
address public health, environmental, economic and social concerns (ACTEW, 2007;
CSIRO, 2003; Lohman, 1987; WateReuse California, 2010).
Professionals in the water reuse field recommend maintaining a current
understanding of opinions of public sentiment with water reuse applications (Dishman et
al., 1989; WateReuse California, 2010). This is beneficial for two reasons. First, if a
region is struck with the onset of a major drought and water reuse becomes an absolute
necessity, information about the publics’ main concerns is readily available and utilities
may utilize this data to engage and educate the community. Secondly, various attributes
of individuals in specific communities vary and change over time. In order to engage the
public effectively, it is beneficial to know the specific concerns and sentiments of
51
individuals and demographics so targeted, appropriate educational campaigns may be
administered in that community.
The most recent detailed public opinion survey regarding water reuse in Denver,
Colorado was published nearly 30 years ago (Lohman & Milliken, 1985). Findings of this
research aim to update the knowledge base of public opinion of water reuse applications
and support in the Denver metro area.
Major Findings
Environmental Benefits are the Most Compelling Reason to Support DPR
Environmental implications of utilizing DPR resonated as the most convincing
reason to support DPR in the Denver metro area. Table 4.6 shows that half of the
respondents considered the following statement to be a very convincing reason to support
DPR, and nearly all of the respondents considered it to be at least somewhat or very
convincing.
“Using recycled water is good for our environment. The more
recycled water we use, the less we have to take out of rivers,
streams and reservoirs. That’s good for rivers, streams, and the
fish, plants and wildlife that rely on them.”
Statements regarding purification, Denver Water’s pilot study and examples of other
communities that utilize DPR yielded lower percentages of agreement in terms of being a
very convincing reason to support DPR (32%, 32% and 29%, respectively). These results
suggest that the environmental benefits of practicing DPR in the Denver metro area
should be a focal point when engaging the Denver public about implementing DPR.
Several characteristics of the Denver community indicate why environmental
benefits appeal most. Colorado’s Statewide Comprehensive Outdoor Recreation Plan
52
reports that 90% of Coloradans participate in some sort of outdoor recreation.
Furthermore, outdoor recreation contributes $34.5 billion dollars to the local economy
and creates 313,000 jobs (Colorado Parks and Wildlife, 2014). Furthermore, multiple
public comments submitted to the Colorado Water Conservation Board regarding the
state Water Plan include statements advocating for healthy rivers, streams and recreation
considerations (CWCB, 2015). With respect to water supply options impacting the
environment and water reuse, one respondent commented:
“I love this idea! We live nearby to Chatfield reservoir and they
are planning to flood most of the park surrounding it to provide
more drinking water for the area. This will result in a loss of so
much land that we enjoy, and I'm sure will negatively impact many
species of animals and plants living there. It would be great if
there was a different option.”
Another respondent wrote:
“We have to think more about how we can save the planet.”
The environment in Colorado plays an important economic role for the state and is
possibly considered intrinsically valuable to the public. Honing in on this sentiment
would be worthwhile for Denver Water when engaging the public about DPR.
Another explanation for why environmental benefits appeal to survey respondents
is that the area served by Denver Water is chiefly populated with voters who consider
themselves to be democrats (The Coloradoan, 2014). Democrats are typically more
concerned about environmental issues than conservative voters (Gallup, Inc., 2015). Had
the survey been conducted in other counties in Colorado with a higher percentage of
conservative voters, environmental benefits may not have been as convincing. This
emphasizes the importance of determining regional sentiments. A state wide survey of
53
Colorado public opinion on potable water reuse would likely yield variations in opinion
across borders, and the other statements about DPR could be more appealing to
populations in other counties.
Drought and Support for DPR
While experience with drought did not yield a statistically significant difference
on support for IPR or DPR, nearly all respondents found the following statement to be
somewhat or very convincing to support DPR:
“Recycling water is a highly drought-resistant way to help ensure
a reliable supply of water to meet local needs, independent of
climate change or weather.”
This suggests the Denver metro area public has some level of concern about water supply
reliability and would prefer drought resistant options to sustain an ample amount of water
for the future. Furthermore, belief that the Denver metro area could experience a severe
drought in the foreseeable future correlated positively to support for both IRP and DPR
(Table 4.7). One respondent noted:
“I would definitely not be opposed to the reuse of water by any
means, especially in drought situations.”
The evidence suggests that utilizing DPR as a means to provide a more reliable, drought-
resistant water supply would appeal to the Denver metro area public.
De Facto Water Reuse and Support for DPR
Eighty five percent of the respondents found the statement regarding de facto
water reuse to be a somewhat or very convincing reason to support DPR:
“The amount of fresh water on the planet does not change.
Through nature, all water has been used and reused since the
beginning of time across every river system in the world. Using
54
advanced technology to purify recycled water merely speeds up a
natural process—and in fact, the water produced through
advanced purification meets a much higher standard of quality
than what occurs naturally.”
A study conducted by the WateReuse Foundation utilized the concept of de facto
water reuse to determine if acceptance of potable water reuse increased after learning
about the urban water cycle. Visual aids were utilized and most of the participants in the
project felt more comfortable after learning that all water is recycled and used again on
our planet, and that downstream users are often treating diluted effluent for drinking
purposes (WateReuse Foundation, 2013). One of the respondents from the Denver survey
made the following comment regarding de facto water reuse:
“As I was reading through the 6 statements about water purification, I
literally thought to myself ‘I do not care what you say...there is simply no
way I am willing to concede that a strong case was made for drinking
wastewater’. Then I got to the part about this is a natural process which
has happened to every ounce of water I have ever drank. And I stopped
and thought...best way to present this case, bar none.”
The fact that the WateReuse Foundation determined that de facto water reuse increases
acceptance and that 85% of the respondents to this questionnaire found de facto reuse a
very convincing reason to support DPR, educational outreach regarding de facto reuse
and the urban water cycle should be tailored in the Denver community when
implementing DPR.
Climate Change and Support for IPR and DPR
Climate change is another factor that is associated to support for both IPR and
DPR (Table 4.7). Eighty-one percent of the public agrees that climate change could
impact water supplies in the future (Table 4.2). This suggests two sentiments among the
Denver metro area public. First, most of the respondents believe that climate change is a
55
reality. Second, the public has an understanding of how climate change could impact
supply, whether it be through lack of precipitation, increased evaporation from surface
waters or changing patterns in snow melt and runoff. Further investigation is needed to
clarify how the public believes climate change would impact water supply; however,
climate change could be used as a means to communicate the benefits of potable reuse in
the Denver metro area. One respondent commented with regards to water reuse:
“It's [water reuse] a smart idea considering climate change and
the politicians who refuse to believe it is a real concern.”
Familiarity and Knowledge of Recycled Water and Support for Potable Reuse
Familiarity with recycled water and belief that recycled water could alleviate
water supply pressures were significantly associated with public support for both IRP and
DPR (Table 4.7). Interestingly, 79% of the respondents consider themselves to be very or
somewhat familiar with recycled water yet only 27% of the respondents are aware that
Denver Water supplies recycled water in the community. Furthermore, 74% of the
respondents believe that the use of recycled water for potable purposes could alleviate
water supply pressures for the Denver metro area. Combined, these findings suggest that
the Denver public believes they are educated on water reuse and are supportive of it as a
means to alleviate water supply shortages.
“I believe you are headed in the right direction because I see
potable water in use in a lot of parks.”
Several parks in the Denver Water service area are currently irrigated with non-potable
recycled water. Another respondent commented:
“I'm sure that I am not the only person who is a little reluctant to
reuse wastewater for drinking water. I think we're heading in the
right direction. We need baby steps here! Let's start using treated
56
wastewater for irrigation and other indirect processes so the
public can get used to the idea of reusing water. Information
regarding the process and communities using this needs to be front
and center in the news so the public can be more accepting.”
It may be worthwhile for Denver Water to educate the public more on the current
applications of recycled water in the community to increase the level of knowledge about
recycled water uses in Denver, and to prepare the public for a future involving potable
water reuse. Furthermore, it would instill confidence in the public that Denver Water is
capable of supplying safe, recycled water. This could in turn increase the level of trust in
the community for Denver Water, which has been associated to more successful potable
water recycling implementation in other regions (CSIRO, 2003).
Importance of Localized Data Collection
Most of the surveys that have investigated public opinion on potable reuse have
reported associations among demographic variables and opinion. Tables 4.8 and 4.9 show
differences between gender and race with regards to various reuse applications and DPR
statements. In the literature, higher income and education levels correspond to greater
support for IPR and DPR, and age has been inversely associated to support for potable
water reuse. However, neither of these associations was found to be statistically
significant in this research. Additionally, other surveys report that white/Caucasian
individuals are more supportive of potable reuse and more comfortable with water reuse
applications than other ethnicities. In this research, non-white ethnicities were more
comfortable with industrial reuse and cooking with recycled water, and there was not a
statistically significant difference among races and support for IPR and DPR. This
emphasizes the importance of conducting surveys at the local level and not relying upon
57
data about public sentiments in other regions. There are characteristics within given
communities that are distinct and that will dictate opinion and support levels for potable
water reuse.
Furthermore, the fact that some of the demographic attributes of individuals (e.g.
age, income, and education) did not affect opinion of water reuse applications indicates
that there could be other factors to consider when investigating this topic. Perhaps
information about social, economic and environmental costs of non-potable and potable
water reuse applications in the Denver metro area would have had a greater impact on
opinion and support.
Public and Denver Water Employee Comparisons
An opinion comparison of Denver Water employees and the public was
conducted and the employees that responded to the survey may not have necessarily been
individuals that are proficient in water treatment methods and water quality standards.
Table 4.4 shows that Denver Water employees are only slightly more comfortable with
the reuse applications listed than the public. It seems intuitive that individuals who work
for the largest treated water provider in Colorado would be more knowledgeable and
significantly more accepting of recycled water applications. However, individuals in the
finance department who could have responded to the survey may seldom speculate about
water treatment technologies.
In contrast, Table 4.10 shows with statistical significance that Denver Water
employees are more supportive of IPR and DPR than the public. It is interesting to note
that while Denver Water support for IPR and DPR are 85% and 65% respectively,
comfort level with drinking recycled water for Denver Water employees is 38%. The fact
58
that support for potable water reuse is higher than comfort with drinking recycled water
could indicate that Denver Water employees are cognizant that potable water reuse is
necessary for a sustainable water future, but are not quite convinced of the safety of
treating wastewater to potable standards and ingesting the water.
The majority of the public and Denver Water employees are in agreement that
climate change will impact water supplies, drought is in the foreseeable future and the
use of recycled water for drinking purposes could alleviate water supply pressures for the
Denver metro area (Tables 4.2 and 4.3). The fact that the community at large and the
water utility employees are in agreement on these issues is positive. If the public and
utility employees differed on these beliefs, water supply decisions would be more
difficult to manage from a public relations perspective. Denver Water can leverage these
beliefs when implementing water supply projects that do or do not involve potable water
reuse.
Hypotheses and Results
This work did not yield results that called for rejection of the hypotheses that men
would be more supportive than women of DPR or that the general public would be more
supportive of IPR than DPR. This project also demonstrated that comfort levels with
applications of recycled water decreases when human contact with recycled water
increases. The results indicate that as familiarity with recycled water increases, support
for potable water reuse increases. Lastly, belief that (1) climate change will impact water
supplies, (2) drought is in the foreseeable future, and (3) that potable water reuse will
alleviate water supply pressures are associated to support for IPR and DPR.
59
Other findings do not impact these results as much as anticipated. Education, age
and income do not significantly impact support for IPR and DPR for this sample.
Additionally, white/Caucasians and non-white ethnicities show variation in opinions that
are difficult to explain. While white/Caucasian respondents show more comfort with
toilet flushing, and non-white respondents are more comfortable with industrial use and
cooking with recycled water. Also, white/Caucasians found the statements about DPR
water purification and de facto water reuse to be more convincing reasons to support
DPR than non-white respondents. These findings can be leveraged to inform education
and outreach within demographic characteristics to promote support for DPR and target
educational campaigns about water reuse.
1985 and 2015 Survey Results
The study that was completed and published by the Denver Research Institute in
1985 (Lohman and Milliken, 1985) assessed the Denver public’s opinion of water reuse.
When compared to this research, public acceptance of all of the reuse applications has
decreased with respect to percentages of acceptability (Table 4.4). Additionally, 37% of
the respondents that participated in the 1985 research considered themselves to be
familiar with recycled water and of those respondents, approximately 72% “did not mind
or minded a little” with regards to drinking recycled water. These 1985 findings differ
from the 2015 survey as 79% of the 2015 sample considered themselves to be familiar
with recycled water and support for DPR and IPR were 48% and 72%, respectively. The
fact that there is still considerable variation and some change amongst the publics’
opinion and acceptance for water reuse applications in the past 30 years, despite greater
60
overall awareness of water reuse justifies the need for public education on recycled water
use for the Denver metro area.
Limitations and Delimitations to the Research
In this research, by utilizing an online survey provider, the respondent
characteristics were not known. Random sampling was utilized, however it was not
known whether or not the individuals that agreed to take surveys through SurveyMonkey
would be representative of the Denver metro area population. Furthermore, Denver Water
supplies water to suburbs surrounding the city and county of Denver and it is not known
whether an equal representation of the entire metro area responded to the questionnaire.
Delimitations are limitations to the research that are known before conducting an
analysis. Due to limited funding and time, it was only possible to obtain 313 responses
for this study. Additional funds might have yielded more responses to the questionnaire,
and utilizing multiple survey techniques (i.e. telephone, mail and web based) would have
reached a larger sample. Additionally, only individuals with Internet access were able to
take the survey, and this could have eliminated sectors of the population that may not be
able to afford internet access or do not use the internet regularly. Third, individuals that
completed the survey hold accounts with SurveyMonkey and are highly likely to
participate in surveys regularly. This may have impacted the results. Fourth, the
questionnaire only contained 20 questions so the data collected were somewhat limited.
A more in-depth study conducted on a larger sample size could reveal more detailed
characteristics of the Denver metro area population’s view of water recycling and water
related topics. Additionally, the survey was administered in the English language and
those individuals that cannot read and understand English were not able to participate in
61
the survey. This may be the reason that very few non-white ethnic individuals completed
the questionnaire. Lastly, support for IPR and DPR could have changed after having read
the six statements about DPR. Assessing support for IPR and DPR after respondents read
the six statements could have indicated that the information provided impacted opinion of
these potable reuse options.
62
CHAPTER VI
CONCLUSION
The main goal of this research was to explore the opinion of the Denver metro
area public on water reuse with a specific emphasis on potable water reuse and DPR.
Comfort levels with water reuse applications and support for IPR and DPR were
assessed. Concepts regarding water supply challenges from climate change, drought and
water recycling were compared to support for IPR and DPR. Water supply options were
presented and rated by respondents. Six educational statements about DPR were listed
and analyzed for their affect in convincing respondents to support DPR as a water supply
option for Denver. Lastly, results from the Denver public survey were compared to
results from a similar survey conducted in Denver in 1985, and public and Denver Water
employee opinions were compared. Important findings are listed below.
• Environmental benefits are the most compelling reason to support DPR in the Denver metro area.
• The fact that DPR is a drought and climate change resilient water supply option appeals to the Denver metro area public and is associated to support for potable water reuse.
• Information about de facto water reuse and the urban water cycle is a convincing concept to support DPR in the Denver metro area.
• Familiarity with recycled water is associated to higher levels of support for IPR and DPR.
• Localized data collection is necessary to understand regional public concerns and values with regards to water reuse.
63
• Support for and comfort with water reuse applications has decreased in the Denver metro area since 1985.
• Denver Water employees and the Denver public are similar with regards to their comfort levels with various water reuse applications, including drinking.
These findings suggest three major themes that can contribute to actionable
policy. First, awareness and support for potable and non-potable reuse applications has
decreased in the Denver metro area when comparing results from Lohman and Milliken
(1985) to the results of this research. Second, environmental benefits, and drought and
climate change resistance from potable water reuse are effective concepts to leverage
when promoting support for potable reuse in the Denver metro area. Finally, if Denver
Water employees are to be ambassadors of information about water related issues and
water reuse, they could be more knowledgeable, comfortable and supportive with regards
to water reuse applications.
Decades of Silence and the Impact on Water Reuse Acceptance in the Denver metro
area
Decrease in Water Reuse Acceptance
Awareness and acceptance of water reuse has decreased in the Denver metro area
over the past thirty years and comfort with drinking recycled water has decreased
substantially (Table 4.4). This is problematic because recycled water use is likely to
increase in the Denver metro area as water supplies become scarce, and public acceptance
of water reuse applications is necessary to implementation, especially with regards to
potable water reuse. Lohman and Milliken’s public opinion survey on water reuse was
conducted during the period when the Denver Potable Water Reuse Demonstration
64
Project was underway; and when survey participants received additional information
about water recycling and toured the Demonstration plant, their aversion to drinking
recycled water and other reuse applications decreased. Furthermore, while non-potable
reuse is currently applied in Denver, many individuals are not aware, and educational
campaigns about recycled water have been lagging during the past few decades. Because
educational information and Demonstration plant tours resulted in greater acceptance of
water reuse applications during the 1985 research (Lohman, 1989), Denver Water should
revamp water reuse awareness in the Denver metro area public through education by
leveraging local values and beliefs.
Leverage Environmental Benefits, Drought and Climate Change Resiliency in the Denver
Metro Area
It was revealed in this research that the environmental benefits of direct water
recycling was considered the most convincing reason to support DPR. Drought and
climate change resilience were also associated to greater support for potable water reuse.
These findings are beneficial because Denver Water can hone in on these sentiments
when educating and promoting water reuse to the public. Had this survey been
administered in a region where individuals do not recreate outdoors or value the
environment, other sentiments may have yielded more support for potable water reuse.
Therefore, effective education and outreach used to promote potable and non-potable
reuse in Denver should incorporate how recycling water positively impacts the
environment and watershed vitality.
Examples of successful educational campaigns that result in greater acceptance of
potable water reuse could be applied to potable water reuse implementation while
65
leveraging environmental health and water resource resilience. As evidenced in the
literature, treatment facility tours guided by water utility professionals have been
affective in increasing acceptance (ACTEW, 2007; CSIRO, 2003; Lohman, 1989).
Perhaps in addition to providing information about treatment methods during tours, the
amount of fresh water savings that can be attributed to water recycling could be
illuminated. Tour coordinators could go even further by describing or showing images of
the current health conditions of plant and animal species that rely on freshwater in the
environment. This type of information could also be included in brochures, bill stuffers,
informational videos, on websites and signage in locations where recycled water is being
used.
Another method of promoting environmental benefits from water recycling could
be by partnering with environmental organizations such as Environment Colorado or the
Sierra Club. These groups could coordinate with water utilities to provide environmental
indicators regarding positive environmental impacts from water recycling. This
information could be provided through their own educational materials (brochures,
signage, websites, etc.) in addition to the water utility’s media outlets and materials.
While guided tours, information and partnerships may be effective ways to
promote water reuse and the environmental benefits therein, individuals may not be
willing or able to dedicate time to read informational packets or tour treatment facilities.
Therefore, quick and simple snapshots conceptualizing environmental benefits of water
reuse could be utilized. Denver Water’s website could show a graphical indicator of the
amount of water recycled compared to the amount of water diverted out of mountain
streams and reservoirs on a daily or monthly basis. Additionally, Denver Water has
66
traditionally utilized billboards throughout the city to promote the water conservation
campaign, “Use Only What You Need”. This traditional campaign approach could just as
easily be used to educate the public about the benefits of water reuse on the environment
and resilient watersheds. Lastly, the local media could provide coverage on these topics.
However, since the public trusts water utility professionals more than media
representatives in delivering information about water recycling (see Ormerod and Scott,
2012), live interviews with water utility employees would be the most effective way to
communicate these environmental and resource resilient implications of water reuse in
the media.
Empower Denver Water Employees with Knowledge
Denver Water employees may be the most trusted ambassadors of information
about water reuse in the Denver metro area, (Ormerod and Scott, 2012) and this research
revealed that Denver Water employees do not differ considerably from the public in
comfort with potable and non-potable water reuse applications. Denver Water employees
were more supportive of IPR and DPR as water supply options for the future, but were
nearly as uncomfortable with drinking recycled water as the Denver public. Denver
Water employees should be significantly more knowledgeable, comfortable with and
supportive of water reuse if they are to effectively communicate accurate information to
educate the public and promote water reuse applications. Therefore, targeted education is
needed towards Denver Water employees to increase knowledge and acceptance of
recycled water. Similar methods that can be used to educate the public can be applied to
Denver Water employees: guided tours of the recycled water treatment facility,
information provided in the internal Denver Water newsletter and presentations by
67
knowledgeable staff could be offered during lunch hours. To the latter point,
environmental benefits and watershed resiliency impacts from recycled water should also
be included in the employee education so employees may leverage this information when
communicating with the public.
Applicability
Results and lessons learned from this research can be applied to future research on
this topic on an international scale. First, online surveys yield timely responses. However,
the ability to set more detailed criteria on respondent characteristics could increase
representation amongst populations. If funding exists, multiple survey methods could be
utilized (i.e. mail, telephone, in person and online surveys) which would greatly improve
generalization of the sample to the population of interest. Secondly, assessing a local
region’s political views and values prior to developing the survey questions could be
beneficial. While research should not be constructed based on bias towards specific
political or value orientations, understanding these characteristics of a given population
could aid in development of more deep-rooted survey questions. For example, the sample
tested in the Denver metro area found environmental benefits to be a convincing reason
to support DPR. It may have been worthwhile to delve into detailed environmental
consequences of water supply options (e.g. Expand/build reservoirs and dams, IPR and
DPR) to better understand which water supply option appealed to the public most, based
on the information provided. Lastly, the verbiage and layout of the questionnaire was
generally acceptable for respondents to read and understand (refer to comments 2, 14, 52,
63 & 77 in Appendix D), and therefore the questionnaire, or a version of it, could be
administered in other communities.
68
Future Research in the Denver metro area
Denver Water should utilize the information revealed through this research to
inform future studies. First, a survey administered to a larger sample size that is
representative of the population should be completed to make more concrete
generalizations about the opinion of the Denver metro area public on water reuse. In
administering a future survey, Denver Water should focus on climate change, drought
and environmental topics as they relate to potable water reuse. Understanding how these
sentiments resonate within the Denver metro area should be explored at a greater depth in
an effort to understand specific concerns to enable addressing them. Additionally, it
would be worthwhile to investigate why gender and race affect opinion on water reuse.
Perhaps sociological circumstances impact acceptability of water reuse applications.
Secondly, an assessment should be administered to additional stakeholders that
would be impacted by additional reuse of Denver’s municipal wastewater. For example,
in San Gabriel Valley, California, Miller Brewing Company raised concerns about how
potable reuse would affect their water quality which contributed to failure of a potable
water reuse project (CSIRO, 2003). Industries and commercial entities should be
analyzed to determine their concerns to allow Denver Water to address issues that would
lead to opposition to potable reuse projects. Additionally, upstream and downstream
stakeholders should be involved in the initial discussions regarding potable water reuse to
address their concerns since these stakeholders would also be impacted by additional
reuse of Denver’s municipal wastewater.
Lastly, this survey did not include statements or questions that address some of
the open questions raised in previous research. It would be worthwhile to administer a
69
survey in Denver metro area that addresses public trust in Denver Water. Previous
research has shown that trust in the water providing entity correlates to more support for
water reuse (Ormerod and Scott, 2013). Additionally, the questionnaire did not address
concerns about CECs. It would be beneficial to understand the Denver area public’s
concern regarding trace metals, pharmaceuticals and personal care products in recycled
water. Voter orientation was not assessed in this research and it would be advantageous
to understand how political views associate to opinion on water reuse. Finally, it would
be interesting to determine if there is a difference between individuals that have children
versus those that do not with regards to acceptance of potable reuse.
Theoretical and Additional Policy Implications
Theoretical
This study reiterates the importance of conducting localized surveys with regards
to potable water reuse. If the questionnaire were administered in a different region of the
United States or world, environmental benefits, drought and climate change may not have
resonated in the same manner as a convincing reason to support DPR. For example,
drought is on the forefront of concern in regions in the arid American West and
individuals who reside in areas that do not anticipate drought in near future could likely
be less convinced of implementing DPR as a means to augment water supplies based on
the threat of a drought. Secondly, many of the demographic characteristics regarding
public opinion of water reuse in other regions did not prove to be significant in the
Denver metro area. This may be due to the research limitations, however it could also be
attributed to variations amongst public traits across regions. For these reasons,
70
communities that intend to implement potable water reuse should understand the
characteristics of the public prior to implementation.
Policy
Major findings and lessons learned from this research can be utilized to influence
water policy. Seventy-two percent of the respondents strongly or somewhat support IPR,
and nearly half of the respondents support DPR as a water supply option. Denver Water
should consider these reuse applications for the future. The fact that the respondents
value the environmental benefits of DPR (which would also result from utilizing IPR)
informs policy makers that water supply options that have less negative impacts on the
environment would be preferred. This should be considered when determining how to fill
water supply gaps in the Denver metro area.
Additionally, Colorado policy makers should consider allowing for more water
reuse applications in the state such as toilet flushing and edible crop irrigation. Results
from the survey indicate that 84% of the respondents are comfortable or somewhat
comfortable with toilet flushing, and 75% of the respondents are comfortable or
somewhat comfortable with irrigating edible crops with recycled water. Increasing the
amount of recycled water applications will yield additional year round uses, could lead to
lower demand of freshwater, and the environmental benefits to local watersheds would be
appreciated by the Denver metro area public.
71
REFERENCES
1. ACTEW Corporation (2007) Community Consultation Report.Report on the
community consultation undertaken on theWater2WATER proposal. July 2007. Available: http://www.actew.com.au/publications/CommunityConsulatationReport.pdf
2. Asano, T. (ed.) (1985) Artificial Recharge of Groundwater. Butterworth Publishers. Boston, MA.
3. Asano T, Burton F. L., Leverenz HL, Tsuchihashi R., & Tchobanoglous G. Water Reuse - Issues, Technologies, and Applications. 1st ed. New York: Metcalf & Eddy, Inc.; 2007:1-1528.
4. Australia Academy of Technological Sciences and Engineering. (2013). Drinking Water Through Recycling; The Benefits and Costs of Supplying
Direct to the Distribution System. Melbourne, Australia: Khan, S. Dr.
5. AWWA. (1994) Dual Distribution Systems. AWWA Mannual M24, 2nd ed. American Water Works Association, Denver, CO.
6. Babbie, E. (2013) The Practice of Social Research. 13th ed. Wadsworth, Cengage Learning.
7. Baumann, D. D. (1983) Social acceptance of water reuse. Applied Geography. 3, (79-84).
8. Bell, G.E.C. and J. Aranda. (2005) Corrosion Engineering Training. Hawaii Water Environment Association. Corrosion Workshop, Feb. 16, 2005. Honolulu, HI.
9. Bischel, H. N., Simon, G. L., Frisby, T. M. & Luthy, R.G. (2012) Management Experiences and Trends for Water Reuse Implementation in
Northern California. Environmental Science and Technology. 46, 180-188.
72
10. Brennan, M. (2012, December). America’s 20 Fastest Growing States. Forbes
Magazine. Available at www.forbes.com/pictures/mhj45mhlf/16-denver-co/
11. Bouwer, H. (1978) Groundwater Hydrology. McGraw-Hill, New York.
12. Burvold, W.H. (1972). Public attitudes toward reclaimed water. U.S. Bureau of Reclamation, Sacramento Office Library.
13. Bruvold, W.H., Olson, B.H, & Rigby, M. (1981) Public Policy for the use of
Reclaimed Water. Environmental Management. 5 (2): 95-107.
14. Bruvold, W.H. (1998) Public opinion on water reuse options. Journal of Water Pollution Control Federation. 60(1), 45-50.
15. Burstein, P. (2003) The Impact of Public Opinion on Public Policy: A Review
and an Agenda. Political Research Quarterly 2003, 56: 29 DOI: 10.1177/106591290305600103.
16. Carr, S., Nortcliff, S., & Potter, R.B. (2010) Water reuse for irrigated
agriculture in Jordan: challenges of soil sustainability and the role of
management strategies. Philosophical Transactions of The Royal Society. 368. DOI 10.1098/rsta.2010.0181.
17. City of Wichita Falls, TX. (2006-2014). Direct Potable Reuse Project. Retrieved from http://www.wichitafallstx.gov/index.aspx?nid=1595.
18. Coloradoan, The. (2014). Map: Colorado Voter Party Affiliation by County. Retrieved from http://www.coloradoan.com/story/news/politics/elections/2014/10/16/map-colorado-voters-party-affiliation-by-county/17379853/ on October 8, 2015.
19. Colorado Parks and Wildlife. (2014) Statewide Comprehensive Outdoor
Recreation Plan. Retrieved on October 3, 2015 from http://cpw.state.co.us/Documents/Trails/SCORP/SCORPOnlineReport.pdf
20. Colorado Water Conservation Board-CWCB. 2015. Colorado’s Water Plan. Available at www.coloradowaterplan.com. Retrieved on January 2, 2015.
73
21. Condie, L.W., Lauer. W.C., Wolfe. G.W., Czeh. E. T. & Burns. J.M. (1994). Denver Potable Water Reuse Demonstration Project: Comprehensive Chronic
Rat Study. Food and Chemical Toxicology. Vol. 32. No. 11. pp. 1021-1030.
22. CSIRO. (2003). CSIRO Land and Water Technical Report 54/03, Literature
Review of Factors Influencing Public Perceptions of Water Reuse. Australia: Po, M., Kaercher, J.D. & Nancarrow, B.E.
23. Dahl, R. (2014) Potable Reuse Strategies Gain Traction. Environmental Health Perspectives. Vol. 122, No. 12. http://ehp.niehs.nih.gov/122-A332/
24. Denver Water. (2014) Retrieved from: www.denverwater.org on October 22, 2014.
25. Denver Water. (2002). Water for Tomorrow: An Integrated Water Resource Plan. Retrieved from: http://www.denverwater.org/SupplyPlanning/Planning/IntegratedResourcePlan/ on October 22, 2014.
26. Dishman, M.C., Sherrard, J.H., & Rebhun, M. (1989) Gaining support for
direct potable water reuse. Journal of Professional Issues in Engineering. Vol. 115, NO. 2, 154-160.
27. Dolnicar, S., Hurlimann, A., & Grun, B. (2011) What affects public
acceptance of recycled and desalinated water? Water Research. 45, 933-943.
28. Du Pisani, P.L. (2005) Direct Reclamation of Potable Water at Windhoek’s Goreangab Reclamation Plant. 193-202 in S.J. Khan, A.I. Schafer, M.H. Muston (eds.) Integrated Concepts in Water Recycling. University of Wollongong, NSW, Australia.
29. EBSCO Publishing. (2014) RELYING ON REUSE. American City and
County, 129(4), 13.
74
30. Friedler, E., Lahav, O., Jizhaki, H., & Lahav, T. (2006) Study of urban
population attitudes towards various wastewater reuse options: Israel as a
case study. Journal of Environmental Management 81, 360-370. Elsevier Ltd.
31. Gallup, Inc. (2015) In U.S., Concern About Environmental Threats Eases. Retrieved from http://www.gallup.com/poll/182105/concern-environmental-threats-eases.aspx?g_source=ENVIRONMENT&g_medium=topic&g_campaign=tiles on October 9, 2015.
32. Granello, D.H. & Wheaton, J. E. (2004) Online Data Collection: Strategies
for Research. Journal of Counseling and Development. (82) 387-393.
33. Hartley, T.W. (2006) Public Perception and participation in water reuse. Desalination 187: 115-126.
34. Houston, S. S., N.L. Barber, J.F. Kenny, D.S. Lumia, and M.A. Maupin. (2004) Estimated Use of Water in the United States in 2000. U.S. Geological Survey, Circular 1268. Reston, Virginia.
35. Hurlimann, A. & Dolnicar, S. (2010) When Public Opposition Defeats
Alternative Water Projects-the Case of Toowoomba Australia. Water Research, 44(1), 287-297.
36. IPCC. (2007) IPCC Fourth Assessment Report: Climate Change 2007. Section 3.4.3 Floods and droughts. Retrieved from https://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch3s3-4-3.html on November 6, 2015.
37. Jang, T., Lee, S., Sung, C., Lee, H., & Park, S. (2010) Safe application of
reclaimed water reuse for agriculture in Korea. Paddy Water Environment. 8:227-233. DOI 10.1007/s10333-010-0203-9.
38. Lahnsteiner, J. and G. Lempert. (2005) Water Management in Windhoek/Namibia. Proceedings of the IWA Specialty Conference,
Wastewater Reclamation & Reuse for Sustainability. November 8—1, Jeju, Korea.
75
39. Lauer, W. (1993) Denver’s direct potable water reuse demonstration project:
Final report. Denver Water Department. 1600 W. 12th Ave. Denver CO, 80204. Retrieved from Records and Documentation Department on September 3rd, 2014.
40. Leverenz, H.L., Tchobanoglous, G., & Asano, T. (2011) Direct potable reuse:
a future imperative. Journal of Water Reuse and Desalination. 01.1, 2-9.
41. Lohman, L. & Milliken, G. (1985) Informational/Educational Approaches to
Public Attitudes on Potable Reuse of Wastewater. Denver Research Institute, University of Colorado, Denver.
42. Lohman, L.C. (1987). Potable Wastewater Reuse Can Win Public Support. In: Proceedings of Water Reuse Symposium IV, Denver Colorado, August 2-7, 1987, Published by the AWWA Research Foundation, Denver, Colorado.
43. Lohman, L. (1989). How Water Professionals Look at Conservation, A
Preliminary Report. Published in Proceedings of Colorado Water Engineering and Management Conference, Fort Collins, February 28, 1989.
44. Martin, L. (2014, September 16) Texas Leads The Way With First Direct Potable Reuse Facilities In U.S. Water Online. http://www.wateronline.com/doc/texas-leads-the-way-with-first-direct-potable-reuse-facilities-in-u-s-0001
45. Meeker, M. (August 12, 2014) WateReuse Past, Present, and Future. Retrieved from https://www.watereuse.org/sections/colorado on August 30, 2014.
46. National Research Council. (2012) Water Reuse: Potential for Expanding the
Nation’s Water Supply Through Reuse of Municipal Wastewater. The National Academies Press. ISBN 978-0-309-25749-7.
47. Ormerod, K. J. & Scott, C. A. (2012). Drinking Wastewater: Public Trust in
Potable Reuse. Science, Technology, and Human Values. 38: 35.
76
48. Reisner, M. (1986) Cadillac Desert: The American West and Its Disappearing
Water. New York, NY. 1st Ed. Viking Penguin Inc.
49. Rock, C., Dolop, F.I., & Gerrity, D. (2012) Survey of statewide public
perceptions regarding water reuse in Arizona. Journal of Water Supply: Research and Technology-AQUA. 61.8, 506-517.
50. Sloan, D.W., Wingert, C. and Cadena, I. (2010) “Potable Reuse in the Permian Basin.” Presented at the 25th WateReuse Symposium, Washington, D.C. Retrieved from https://www.watereuse.org/sites/default/files/u3/David%20Sloan.pdf on September 20, 2014.
51. State of California. (2014). California Drought. Retrieved from http://ca.gov/drought/ on October 18, 2014.
52. Todd, D.K. (1980) Groundwater Hydrology. John Wiley & Sons, New York.
53. U.S. Bureau of Reclamation. (2005). Water 2025: Preventing Crises and
Conflict in the West. Retrieved from: http://biodiversity.ca.gov/Meetings/archive/water03/water2025.pdf. on September 20, 2014.
54. US EPA. (1998) Water Pollution Control—Twenty-five Years of Progress and
Challenges for the New Millennium, 833-F-98-003,Office of Water, U.S. Environmental Protection Agency, Washington, DC.
55. Water Environment Research Foundation. (2015) Considering the
Implementation of Direct Potqable3 Reuse in Colorado. Library of Congress Catalog Card Number: 2015945842.
56. Water Research Foundation. (2015) Integrated Water Management: Planning
for Future Water Supplies (Project #4550). Water Research Foundation.
77
57. WateReuse California. (2010). Public and Political Acceptance of Direct
Potable Reuse. Sacramento, CA: Millan, M. and Nellor, M.H.
58. WateReuse Foundation. (2006). An Economic Framework for Evaluating the
Benefits and Costs of Water Reuse. WateReuse Foundation. ISBN: 0-9747586-9-8.
59. WateReuse Foundation. (2009) The Psychology of Water Reclamation and
Reuse. WateReuse Foundation. ISBN: 978-1-934183-21-2.
60. WateReuse Foundation. (2011). Direct Potable Reuse – A Path Forward. WateReuse Research Foundation Report. Alexandria, VA: Tchobanoglous, G., Leverenz H., Nellor, M. and Crook, J.
61. WateReuse Foundation. (2013). Downstream: Context, Understanding,
Acceptance: Effect of Prior Knowledge of Unplanned Potable Reuse on the
Acceptance of Planned Potable Reuse. Retrieved from https://www.watereuse.org/catalog/research-reports/potable-reuse August 20, 2014.
62. WateReuse Foundation. (2014b) Risk reduction for direct potable reuse. Salveson. A, Mackey. E, Salveson, M. & Flynn. M. Retrieved from https://www.watereuse.org/catalog/research-reports/potable-reuse on September 20, 2014.
63. WateReuse Foundation. (2015a) California Direct Potable Reuse Initiative:
Reporting on Significant Progress. Retrieved from https://www.watereuse.org/wp-content/uploads/2015/01/Direct-Potable-Reuse-Progress-Report-2015-Fall-Winter.pdf on November 6, 2015
64. WateReuse Foundation. (2015b). Model Communication Plans for Increasing
Awareness and Fostering Acceptance of Direct Potable Reuse. Millan, M., Tennyson, P. & Snyder, S. ISBN: 978-1-941242-18-6.
65. White, A. (February 7, 2013) Water-Reuse Ideas Go Forward, Despite ‘Toilet to Tap’ Concerns. New York Times. Retrieved from
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http://www.nytimes.com/2013/02/08/us/potable-water-reuse-ideas-go-forward-in-texas-despite-concerns.html?_r=0 on September 20, 2014.
79
APPENDIX A
ADVANCED WASTEWATER TREATMENT METHODS
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Treatment Objective Applied Methods Function
Removal of Suspended Solids Clarification Removes nutrients, heavy metals, and reduce NH4+ to NH3
Sand and media filtration Porous beds of granular media that filter particles through sieving and/or adsorption
Microfiltration and ultrafiltration Thin, porous membranes that collect solid material by sieving
Removal of Dissolved Chemicals Reversed Osmosis
Reduces concentration of dissolved organic compounds by reducing total organic carbon
Adsorptive treatement Total dissolved solids adsorb to granular or powdered activated carbon
Advanced oxidation
Hydroxyl radicals convert organic chemicals to CO2 and non-organic species through UV light or addition of O3 to H2O2
Disinfection Chlorination
Chlorine reacts with water to produce disinfectant hypochlorous acid and hypochlorie ion, kills harmful pathogens
Ozonation O3 kills bacteria and cysts, reduces Fe and Mn, removes taste, odor, and color
Ultraviolet light
Light wavelenghts penetrate cell walls of microorganisms killing cells or preventing replication
Stabilization pH, alkalinity, lime
Restores mineral content to improve taste, minimize soil damage, and reduce corrosiveness on distribution system
81
APPENDIX B
COMIRB CERTIFICATE OF EXEMPTION
82
Colorado Multiple Institutional
Review Board, CB F490
University of Colorado,
Anschutz Medical Campus
13001 E. 17th Place, Building
500, Room N3214 Aurora,
Colorado 80045
303.724.1055 [Phone]
303.724.0990 [Fax]
COMIRB Home Page [Web]
comirb@ucdenver.edu [Email]
FWA00005070 [FWA]
University of Colorado Hospital Denver Health Medical Center Veteran's Administration Medical Center Children's Hospital Colorado University of Colorado Denver
Colorado Prevention Center
Certificate of Exemption
18-Aug-2015
Investigator: Brandi Honeycutt Subject: COMIRB Protocol 15-0843 Initial Application Review Date: 8/14/2015 Effective Date: 14-Aug-2015 Anticipated Completion Date: 13-Aug-2018 Sponsor(s): None~ Title: Public Perceptions of Water Reuse in Denver Exempt Category: 2 Submission ID: APP001-1
SUBMISSION DESCRIPTION
Initial Exempt
Submission
Your COMIRB Initial submission APP001-1 has been APPROVED FOR EXEMPTION.
Periodic continuing review is not required. For the duration of your protocol, any change in the
83
experimental design/content/personnel of this study must be approved by COMIRB before
implementation of the changes.
The anticipated completion date of this protocol is 13-Aug-2018. COMIRB will administratively
close this project on this date unless otherwise instructed by e-mail to COMIRB@ucdenver.edu.
If the project is completed prior to this date, please notify the COMIRB office in writing or by e-
mail once the project has been closed.
Study personnel are approved to conduct the research as described in the documents
approved by COMIRB, which are listed below the REVIEW DETAILS section. Please carefully
review the REVIEW DETAILS section because COMIRB may have made red-line changes (i.e.
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Information on how to submit changes (amendments) to your study and reports of unanticipated
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Contact COMIRB with questions at 303-724-1055 or COMIRB@ucdenver.edu.
REVIEW DETAILS: APPROVED FOR EXEMPTION (Category 2)
Documents reviewed and stamped APPROVED FOR EXEMPTION or NOTED to make this
determination of exemption include: 1. Application Form; version 08/01/2015
2. Personnel Form; no version date
3. Student Mentor Responsibility Agreement; version 07/17/2015
4. Survey; version 08/01/2015
Affiliated Site(s): UCD Downtown Campus
Sincerely, UCD Panel IS Please provide Feedback on Your Experience with the COMIRB Process
84
APPENDIX C
SURVEY INSTRUMENT
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90
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94
95
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98
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APPENDIX D
RESPONDENT COMMENTS
100
Number Response Text
1 we still have some clean fresh water here
2 interesting and worthwhile best survey yet
3 no comment
4 none
5 NONE
6 It is an interesting project
7 Thank you!
8 The biggest doubt is the need to be 100% accurate in control of the purification process. All of Denver's treated water currently goes down stream for other communities to include in their water supplies. They drink it. Why shouldn't we? Mixing the water provides one further control to assure that if some re-purification step is compromised, any contaminants will be further diluted.
9 I love this idea! We live nearby to Chatfield reservoir and they are planning to flood most of the park surrounding it to provide more drinking water for the area. This will result in a loss of so much land that we enjoy, and I'm sure will negatively impact many species of animals and plants living there. It would be great if there was a different option.
10 Am very comfortable with water reuse.
11 The issue is really to stop use of water for all consumptive purposes (stop growing blue grass and trees).
12 Best of luck with the research=)
13 None
14 Very nicely done.
15 I do not want to drink recycled water, period. The very idea disgusts me, no matter how supposedly "safe" it is. I have no problem with it for toilets or for landscaping, however.
16 good
17 None
18 good to know this stuff
19 like
20 The location of text was often confusing.
21 I Totally Disagree With Recycling Water Because I'm Totally Against Such
22 I had issues with the survey (perhaps because I took it on my phone) My responses to the rating question were 1) indirect 2) direct 3)expanding current reservoirs 4) building new dams.
23 Don't interfere with nature
24 we have to think more about how can we save the planet
25 I think that this is an awesome concept; especially if there is already 20+ years of data supporting it. Good luck!
26 If we want to experiment on reusable sewage, let's do it in California right now!
27 This concept needs to be expanded and introduced to the public. Education of the benefits is obvious and implementation will benefit all.
28 n/a
29 I believe recycled water will definitely be needed in the future. In my case, I think it's
101
a matter of mind over matter that holds me back from drinking recycled water. I do not have a problem with it being used for irrigation of lawns or for farming. Good luck on completing this study.
30 Question asking for rating of choices: did not allow me to choose my choices..just stayed 1,2,3,4
31 I consider this to be very important and timely.
32 we recycle water , because there remains much
33 I would like to see some type of reclaimed water usage in the Denver metro area.
34 I'm game
35 good water is from Colorado and we don’t need to share with anyone
36 The only question I would have is: Does purified to the highest standard include filtering out such pathogens as cryptosporidium parvum? If so, then I would be all for it.
37 None
38 The idea of taking waste water from toilets and somehow recycling that same water back around for my family to drink disgusts me!!!!!
39 give us fresh water that's what everyone need
40 The water in Englewood is terrible and answers are based primarily on that. Every other area in Denver Metro area have been fine.
41 I am happy with water reuse
42 bvgfre
43 Funny. I was actually thinking to myself "I would really like to leave this person a comment..." As I was reading through the 6 statements about water purification, I literally thought to myself " I do not care what you say...there is simply no way I am willing o concede that a strong case was made for drinking wastewater" then I got to the part about this is a natural process which has happened to every ounce of water I have ever drank. And I stopped and thought...best way to present this case, bar none. Well, good luck. I am off to google how long I can live without water.
44 I would definitely not be opposed to the reuse of water by any means, especially in drought situations. There is proof in Texas and Africa, that this is in fact safe. It is hard to get past the fact that you would be drinking water that at one point was sewage, but if need be, what choice do we have?
45 -
46 Besides the normal things that are flushed down toilets like urine and feces and toilet paper, there are other wastes like vomit and the blood of the menstrual cycles of women that are also added to the sewer system. I find it difficult to believe that these biohazardous wastes are able to be so totally filtered out of the contents of the sewer systems. I would rather that we not risk finding out that we missed a microorganism -- oh, we thought this was safe drinking water! -- after someone gets sick and dies.
47 N/A
48 I welcome any efforts Denver/Colorado/the US take to conserve resources and curb climate change.
49 NONE
50 N/A
51 We should be concerned about the planet.
102
52 This is a great survey. I love being from this state. ^^
53 I find very interesting this survey
54 i feel safe drinking the water that flows down from the snow packed mountain
55 I would like to learn more about our water supply and your studies.
56 good
57 My biggest problem is the integrity of those who will be handling the filtering and processing of the water to be reused. There is no trust in those individuals (Unless you hire all Mormons - and I'm Catholic). Integrity falls by the wayside where there is a bottom line involved.
58 No comment
59 no comment .. thanks
60 I believe you are headed in the right direction because I see potable water in use in a lot of parks. I also believe you would not risk the health of the people
61 That is well.
62 clean water plz
63 Good job and good luck!
64 none
65 I AM REALLY EXCITED TO SEE THIS PROJECT MOVE FORWARD!!
66 none
67 Very interesting facts presented. I hope others will be convinced that direct recycling of water is a great idea!
68 Very interesting survey! I just got back from California where they are in a 7-year drought. We have to do something! Good to know there are options!
69 none
70 Having read about water reuse, I know it is going to be a reality; however, getting past the idea of drinking sewer water is a different reality. Good Luck
71 It's a smart idea considering climate change and the politicians who refuse to believe it is a real concern
72 none
73 Nothing
74 Denver is growing very rapidly and needs to conserve all the water it can
75 Sounds good; but what about the chemicals they use to clean water - how much ill effects on our bodies will that have 20 years down the road
76 Good research
77 somewhat agree with most everything but not sure about drinking - one of better surveys I have taken
78 I'm sure that I am not the only person who is a little reluctant to reuse waste water for drinking water. I think we're heading in the right direction. We need baby steps here! Let's start using treated waste water for irrigation and other indirect processes so the public can get used to the idea of reusing water. Information regarding the process and communities using this needs to be front and center in the news so the public can be more accepting.
79 Very interesting survey!
80 denver is one of the best place in the world for fresh water
81 After reading the statements about studies and previous use of the system, I think recycling water is not as worrisome as I thought. If the claims are true, this seems like a reasonable way to ensure Denver has enough water. I would need to see the research, however.
103
82 Drinking water is a very minor use of municipal water. We should use direct delivery of retreated sewer water for agricultural, industrial and landscape needs not drinking. The risk of a processing mistake sickening a large population are too high for home use.
83 You made me think about it. Thanks ..
84 Very interesting survey and much needed research!
85 At the end of the day, if all we are supplying Denver with is Hydrogen and Oxygen in the proper ratio, free of any pollutants, then who am I to judge where the water originated from? As long as the purification process is appropriately executed, observed for quality control, and equipment inspected and maintained frequently, there is no reason not to pursue the creation and use of recycled water. Recycling waste is not only a good resource for water, dehydrated waste is used as an alternative fuel source. It's a win-win.
86 All avenues, including dams must be used to save Colorado water from flowing out of the state.
87 Many countries are lacking in water, so unnecessary usage of water must be avoided such as water fountains
88 NONE. THANKS
89 Too many drugs, hormones etc. are in the waste water these days that were not present many years ago. To remove them is questionable
90 Good
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