Subido por Rodolfo Graña

adwr20201012-dl

Anuncio
ADVANCES WATER
October–December 2020 | vol.30 no.4
in
RESEARCH
A Publication of The Water Research Foundation
microorganisms
also in this issue
Responding to the Pandemic
Biofiltration
Microbiome Study
Natural Assets
VIEWPOINT
Innovation
W
ater utilities face a wide array of challenges, including a growing
number of regulatory requirements, deteriorating infrastructure,
climate uncertainty, an aging workforce, affordability challenges,
and much more. The water sector is seeking innovative ways to address these
pressures, and many utilities are working to stimulate the development of novel
ideas and partnerships. These utilities recognize that in order to thrive, the
water sector must develop a culture that supports creativity and manages
ideas as valuable resources.
The Water Research Foundation (WRF) strives to foster this culture within the
water sector, and to create an environment that helps innovative ideas flourish.
Innovation is woven throughout all we do, including our research programs; collaborative technology evaluation trials;
demonstrations of innovative technologies; and the Leaders Innovation Forum for Technology (LIFT), an initiative we
share with the Water Environment Federation.
Innovative approaches are not just about new and creative practices, but also about the people behind them. With
that in mind, Advances in Water Research now includes a section dedicated to WRF’s innovative scientific and technical
advancements, people, and stories. In this issue, Houston Water, under the leadership of WRF board member Yvonne
Forrest, shares its involvement in the Scholarship Exchange Experience for Innovation & Technology (SEE IT), which
provides utilities with opportunities to see innovative technologies and practices first-hand before adopting these
technologies themselves.
Innovation within the water sector is increasingly important as the challenges that communities face become more
complex. The water sector cannot address the needs of the future by doing things the way we’ve done them in the
past; we must explore new and unique approaches in order to succeed. WRF is your trusted source for water research
and innovation, and we look forward to working with you to identify and pursue key opportunities that will further
enable the sector to meet the needs of the communities we serve.
Dennis W. Doll
Peter Grevatt, PhD
Chair, Board of Directors
Chief Executive Officer
ii
October–December 2020 • Advances in Water Research
CONTENTS
VOL. 30 NO. 4
ii |
Viewpoint:
Innovation
2|
4|
7|
By the Numbers:
Biofiltration
The Water Research Foundation (WRF)
is the leading research organization
advancing the science of all water to
meet the evolving needs of its subscribers
and the water sector. WRF is a nonprofit,
educational organization that funds,
manages, and publishes research on the
technology, operation, and management
of drinking water, wastewater, reuse,
and stormwater systems—all in pursuit
of ensuring water quality and improving
water services to the public.
Q&A: Interview with WRF’s 2020
Outstanding Subscriber Award Winners
Advances in Water Research Statement of
Ownership, Management, and Circulation
Owned by The Water Research Foundation,
6666 West Quincy Avenue, Denver, CO 80235.
Publisher: The Water Research Foundation;
Editor: Alyse Greenberg; Bondholders: None;
Circulation: Average number of copies distributed per month for 12-month period (October
2019 – September 2020) – 8513 as follows: paid
and/or requested mail subscribers – 8413; free
distribution – 100.
This statement has been filed on PS form 3526
with the USPS on 11/17/20 and is published
herein in accord with USPS regulation 39
USC 3685.
Responding to the Pandemic
11 |
Intelligent Water Networks
12 |
Innovation in Action: Q&A
with Aisha Niang
Editor: Alyse Greenberg
P 303.347.6116 • editor@waterrf.org
Copyeditor: Barbara Swartz
Art director: Cheri Good
Customer service
P 888.844.5082 or 303.347.6100
info@waterrf.org
14 |
24 |
25 |
29 |
Biofiltration: 30 Years of
Research and Guidance
Modeling Collection System
Greenhouse Gases
Management of Natural
Assets
Trace Organic Compounds
Advances in Water Research • October–December 2020
20 |
24 |
28 |
29 |
Chicago Area Waterway
System Microbiome Study
Transportation Biofuel
Development
Manganese Control
Lead Service Line
Identification
Advances in Water Research
(ISSN 1055-9140) is published quarterly
for $100 a year in North America by
The Water Research Foundation,
6666 W. Quincy Ave., Denver, CO
80235-3098
Telephone: 303.347.6100
Periodicals postage paid at Denver, CO.
Postmaster: Send address changes to
Advances in Water Research, The Water
Research Foundation, 6666 W. Quincy
Ave., Denver, CO 80235-3098
Copyright © 2020 The Water Research
Foundation. ALL RIGHTS RESERVED.
No part of this publication may be copied, reproduced, or otherwise utilized
without permission. Published in the
U.S.A. Printed on recycled paper.
BY THE NUMBERS
This installment of By the Numbers provides statistics on biofiltration and its use in
drinking water treatment. For more information on this subject, see the article,
Biofiltration: 30 Years of Research and Guidance.
Biofiltration is the process of allowing microorganisms to colonize water treatment filters in order to remove
biodegradable compounds from water. There are many drivers for, and benefits of, implementing biofiltration.
Drivers for biofiltration identified by utilities participating in
North American Biofiltration Knowledge Base
Biofiltration can effectively reduce levels of various constituents, including total organic carbon, manganese,
iron, ammonia, and geosmin.
The ability of biofilters to remove contaminants is specific to the facility and target contaminant
Total Removal Potential
Contaminant Class
Typical Contaminant Parameter
Biofiltration Only
Biofiltration with
Pre-ozonation
Removal Rates
High (with appropriate High (with appropriate
Data not available
particle conditioning) particle conditioning)
Particles, Pathogens
Turbidity
Oxidation Byproducts
Assimilable organic carbon (AOC), Biodegradable dissolved
Moderate to High
organic carbon (BDOC), Carboxylic acids, Aldehydes, Ketones
Disinfection Byproduct (DBP)
Precursors (Natural
Organic Matter)
High*
AOC: up to 220 µg-C/L
Trihalomethanes, Haloacetic acids, N-nitrosodimethylamine,
Low to Moderate
Total organic carbon (TOC)
Moderate
TOC: 10–20%
DBP formation
potential: 20–50%
Algal Metabolites
2-methylisoborneol (MIB), Geosmin, Cyanotoxins
Moderate to High
High
MIB/geosmin: >99%
Anthropogenic Compounds
Endocrine disrupting compounds, Pharmaceuticals and
personal care products, Pesticides
None to Moderate
None to High
Data not available
Inorganic Compounds
Iron, Manganese, Ammonia
None to High
Moderate to High
Manganese: 25–80%
* Removal may decrease with lower temperatures
Source: Adapted from Brown et al., forthcoming
2
October–December 2020 • Advances in Water Research
biofiltration
As research demonstrates the effectiveness of biofiltration, the use of biofilters has increased.
Biofilter installation at 43 facilities submitting data to the
North American Biofiltration Knowledge Base
180
Cumulative Percentage of Filters
Sum of Number of Filters
Number of Biofilters Installed
160
100%
90%
80%
70%
140
120
60%
50%
40%
100
80
60
30%
20%
40
20
10%
0%
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2054
2006
2076
2008
2098
2010
2010
2012
2013
2014
Unknown
0
Year Installed
Source: Brown et al. 2016.
WRF has supported a significant amount of research to advance the water sector’s understanding
of biofiltration.
37
Biofiltration projects funded by WRF
$4,246,123
Cumulative value of the six projects conducted through WRF’s
Biofiltration: Defining Benefits and Developing Utility Guidance
Research Area.
References
BROWN, J., G. Upadhyaya, J. Carter, T. Brown, and C. Lauderdale. 2016. North American Biofiltration Knowledge Base. Project 4459. Denver, CO: Water
Research Foundation.
BROWN, J., G. Upadhyaya, J. Nyfennegger, G. Pope, S. Bassett, A. Evans, J. Carter, V. Nystrom, S. Black, C. Alito, C. Lauderdale, J. Hooper, B. Finnegan, L.
Strom, L. Williams Stephens, E. Palmer, E. Dickenson, S. Riley, E. Wert, L. Weinrich, and P. Keenan. Forthcoming. Biofiltration Guidance Manual for
Drinking Water Facilities. Project 4719. The Water Research Foundation.
Advances in Water Research • October–December 2020
3
Q&A
Interview with WRF’s 2020
Outstanding Subscriber
Award Winners
O
n September 1st, WRF presented the 2020Out-
their treatment, delivery, and/or management processes
standing Subscriber Awards for Applied Research
through the successful application of WRF research. WRF
to Hampton Roads Sanitation District (HRSD)
interviewed representatives from each of these utilities
and Metro Vancouver (MV). This award honors subscrib-
to learn more about their dedication to applied research
ing utilities that have made notable improvements to
and innovation.
Hampton Roads Sanitation District
Charles Bott, PhD, PE, BCEE, Director of Water Technology and Research
What does winning WRF’s
research, in addition to issue-
Outstanding Subscriber Award
based research. With so many
mean to Hampton Roads San-
emerging technologies, so many
itation District (HRSD)? We’re
emerging needs for new tech-
quite proud because we value
nology in the wastewater and
the work that WRF is doing. The award acknowledges that
reuse sectors, and so much capital that will be spent on this
we have been an important contributor to research. We have
infrastructure in coming years, technology-based research
many people contributing to projects, serving on PACs, on
can’t be put aside because of the issues of the day. There’s
the Research Council, etc. We also provide in-kind and cash
always a need to balance issue-based research with the
support for research projects that are of interest to HRSD,
evaluation, development, and refinement of new technolo-
and we are directly involved in many WRF research projects.
gies that might be of big benefit to our field. Partial denitrification anammox (PdNA) is an example of that, and WRF
Are there specific projects that HRSD has been involved
is for the most part the only significant national player in
in that you are particularly proud of? There are many. A
funding wastewater and reuse technology-based research.
couple of current ones involve partial denitrification ana-
As HRSD contemplates a capital improvement program
mmox, and now we are excited to have partnered with
of several billion dollars, the value of this type of research
WRF and others to obtain a large EPA grant to continue
cannot be overstated. We must continue to innovate.
our work in this area. Of note, this new work builds on previous WRF projects that go back as much as 10 years on
What are some of the big issues that HRSD is facing, or
mainstream deammonification. We’re really excited about
anticipates facing, where more research is needed? We
the potential technology, we’re excited about the current
have a new large initiative of potable reuse by managed
project, and we’re excited about the future EPA project.
aquifer recharge pending; five treatment plants, 100 mil-
Another new project that is very important to HRSD and
lion gallons per day. This program is known as the Sustain-
just getting started involves ozonation and control of bro-
able Water Initiative for Tomorrow (SWIFT), and we are
mate in potable reuse (5035).
not using reverse osmosis (RO). Rather, SWIFT employs
an ozone/biofiltration/GAC-based approach. We’ve been
You’re on the Steering Committee of the Leaders Innova-
very encouraged by, and eager to participate in, research
tion Forum for Technology (LIFT). What other ways has
projects related to non-RO potable reuse-based technol-
HRSD been involved in LIFT? HRSD is a strong advocate
ogy. The portfolio of WRF research on reuse and those
for WRF to be able to sponsor and fund technology-based
treatment technologies is certainly important. What goes
4
October–December 2020 • Advances in Water Research
Outstanding Subscriber
right along with that is the need for effective low-level
standpoint through emerging technologies, and using
nutrient removal. The nutrient program isn’t finished yet.
appropriate monitoring technologies to confirm that the
There’s a lot of work left to be done to obtain the level
water is safe, is critical. Technologies to make the produc-
of nutrient removal reliability and sustainability that our
tion of whatever quality reuse water is necessary possible
industry demands.
and cost-effective, and monitoring approaches that assure
stakeholders that the water is safe and meets those cri-
How has HRSD used research to further its goals? SWIFT
teria. That is one of the most important pieces. The other
immediately comes to mind. It was the initial work that
piece is that those processes and those technologies are
WRF funded on non-RO processes for potable reuse that
going to require more automation, more sensors, and very
gave us the confidence to push ahead on SWIFT with-
sophisticated control systems. We must be automated
out RO. That has changed our whole organization. WRF
because things move too quickly and there is too much
helped make that happen. From a nutrient removal stand-
happening for a person to address.
point, it was original work by WRF, promoting and conducting projects related to sidestream deammonification
Is HRSD involved in much intelligent water systems work?
that pushed us in that direction, and as an industry, we
Our approach has been very measured and careful in this
then dove headlong into mainstream deammonification.
regard. We look for very specific problems at our treat-
We have landed on PdNA as an important route to get
ment plants and in our collection/conveyance systems
there, but the WRF nutrient research program going back
that need to be solved, and manage those issues using
20 years or so is the reason that we are continuing to move
these more sophisticated tools, then use that as a model
away from our conventional, resource-intensive nitrogen
to move forward looking at ever more complex systems. It
and phosphorus removal processes into whole new areas.
seems that a lot of vendors are claiming it is possible to fix
everything all at once! At HRSD, we are taking small steps
What do you see as the future of the water sector? Water
that folks can understand—identify the specific problem,
shortages are going to continue to drive more and more
understand the objective, develop, test, and implement
reuse opportunities. Making them reasonable from a cost
a solution.
Metro Vancouver
Paul Kadota, MASc, MPA, Collaborative Innovations Manager
What
does
winning
of options for wastewater
WRF’s Outstanding Sub-
sludges. We initiated with
scriber Award mean to
WRF examination of the
Metro Vancouver (MV)?
hydrothermal liquefaction
Having WRF recognize
(HTL) technology that
MV validates that we are
could potentially displace
going in the right direction and continually improving our
anaerobic digesters to more thoroughly convert the car-
operations in the provision of quality water services. I’d
bon that’s being collected by our wastewater treatment
like to thank our senior managers for subscribing to the
facilities, as well as the beneficial microbial biomass we’re
idea that research can lead to invention, which can then
cultivating at our facilities. Working with WRF on HTL
lead to innovation for business improvement. I also want
has been fantastic—to validate the technology, to have
to thank our Board of Directors for having the foresight
an independent third party validate the excellent bench
to set aside resources to fuel good research propositions.
test results. That’s the value WRF provides for these rela-
Without that support, we couldn’t do what we’re doing.
tively risky initiatives that the entire water industry needs
to pursue if we want to push the envelope of innovation.
Are there specific projects you’ve worked on that you’re
particularly proud of? We’re always excited about projects
Are there other big issues that MV is facing, or antici-
that address real pain points, and one has been the lack
pates facing, where more research is needed? What we
Advances in Water Research • October–December 2020
5
Outstanding Subscriber
see on the horizon are the effects of climate change. We
Recently, we’ve been looking into innovation ecosys-
have these global effects that are going to impact the way
tems. If we want to have a continual pipeline of innova-
we do business. We need to do fundamental research to
tions at MV, we need to think more about how we’re inter-
identify better solutions for the adaptation to, and miti-
nally set up for that. The innovation ecosystem needs to
gation of, these global issues. These issues are bringing
have the right people, but also the right framework, tools,
to light that we need to do more with fewer resources.
and culture so that staff are encouraged to experiment
That means efficiency gains, recovering more energy from
with new improvement ideas. MV has done a good job of
wastewater, creating greenhouse gas (GHG) credits, and
providing the monetary resources necessary to test new
reducing costs.
ideas and host new technologies. What we’re struggling
with right now is the time and effort needed to set up
Has MV been implementing actions to address climate
demonstration facilities, largely because we don’t have
change? Our Board set a goal of achieving region-wide
dedicated live-flow spaces for this. We need to create an
GHG neutrality in all sectors by 2050. We need to figure
easier mechanism for testing, and that innovation ecosys-
out our roadmaps towards achieving this target. There
tem needs to be part of what we research and how we go
are a number of roadmaps being formulated, and we’ve
about setting it up in a large organization like MV, and do
engaged the broader community to brainstorm ideas in
it safely without significant risk to our operating facilities.
terms of what we can do in the transportation, building,
The real benefit of being part of the WRF family is that
water, and other sectors. On the liquid waste side, we’re
we share experiences with other utilities. WRF’s initiative
looking at how to capture and use the CO2 that’s gener-
on LIFT and the Utility Analysis and Improvement Method-
ated in our anaerobic digesters—that’s atmospheric cap-
ology provides a fantastic venue for sharing experiences.
ture. We’re also considering hydrospheric capture of CO2.
The duplication of effort can be effectively eliminated by
This might be the next frontier of innovation that we in the
bringing together peer utilities.
water business need to start thinking more about.
What do you see as the future of the sector? We need
How has MV used research to further your goals? Research
to reach out to other sectors and figure out how we can
needs to influence the management of our facilities and
help each other. We can’t just think about water anymore.
have a positive impact on our plans. If our plans change for
I would almost challenge the One Water concept and
the better because of the innovation that we’re examining,
say our future will be more of a One World concept, and
then the design, implementation, and operation of that fol-
we need to integrate our planning with other operating
lows. Along with our collaborators, we research and pilot
industries. For example, connecting with your local energy
a few techniques and technologies ahead of launching
utility or the transportation sector might lead to joint
into things. Research has had a significant role, especially
solutions to address multiple pain points; the high-tech
when we’re making long-term decisions on infrastructure
sector could show us a few things about smart systems,
or changing management methods. It requires in-depth
as well as accelerating innovations. I think that’s where
research into the options to determine which path to fol-
our future outreach needs to go. Everything is a lot more
low. Each jurisdiction will have its own path to investigate.
complicated, more integrated, and we need to learn from
You might have similar issues in other jurisdictions, but the
many other industries and from all fields of science. Let’s
localized situation needs to be taken into account when
venture outside the comfort of our own industry, develop
you’re investigating which management method you want
globally impactful solutions at the local level, and catalyze
to implement.
the establishment of circular economies.
6
October–December 2020 • Advances in Water Research
COVID-19
Responding to
the Pandemic
The Water Research Foundation has taken decisive action to
address concerns and research needs related to the COVID-19
pandemic, and will continue to do so into the foreseeable future.
By Ashwin Dhanasekar, Christobel Ferguson, Stephanie Fevig, Alyse Greenberg, Julie
Minton, Lola Olabode, and Erin Partlan, The Water Research Foundation
Advances in Water Research • October–December 2020
7
COVID-19
T
hroughout the past year, the world has been seeking information about,
and methods to address, the COVID-19 pandemic. Scientific studies
demonstrated that the genetic material of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)—an enveloped RNA virus that
causes the disease COVID-19—can frequently be detected in the feces of
infected individuals. This suggested a strong indication that the genetic
signal of SARS-CoV-2 could be detected in wastewater.
Across the water sector, many
were also represented (Figure 1). The
groups rapidly mobilized to con-
survey showed that 54% of respon-
International Water Research
Summit on COVID-19
duct wastewater surveillance for this
dents were already testing for the
WITH SO MANY ENTITIES AROUND
genetic signal. Wastewater surveil-
genetic signal of SARS-CoV-2, and
the world conducting wastewater sur-
lance is not a new area of research;
the remaining 46% were developing
veillance, there was an urgent need for
it has been critical to detecting the
methods with the intention of initi-
greater coordination to align research
presence of poliovirus and has been
ating testing efforts. The results also
to accelerate progress in this criti-
used to investigate opioid use in
indicated that a wide variety of con-
cal area. To address this need, WRF
communities. What is new, however,
trol organisms is being used as pro-
held the Virtual International Water
is the exploration of its potential to
cess controls, including F-specific
Research Summit on Environmental
provide an integrated, community-
phages (e.g., MS2), Hepatitis G,
Surveillance of COVID-19 Indicators
level indication of the presence
mouse hepatitis virus, murine noro-
in Sewersheds. More than 50 leading
of SARS-CoV-2.
virus, pepper mild mottle virus, and
water experts from utilities, academia,
WRF is dedicated to keeping water
human coronaviruses 229E, OC43,
consulting, and government partici-
sector professionals informed about
and NL63. The survey results will be
pated in working groups focused on
this issue and any measures needed
published soon.
four specific topics:
to protect both water sector workers and public health. To further the
science related to SARS-CoV-2 and
54.3
to provide WRF subscribers and
partners with the most up-to-date
54.3
50
information available, WRF is coordinating efforts including a meth-
40
ods survey, a virtual summit, new
Survey of Wastewater
Surveillance Activities
Percent
research projects, and more.
30
23.9
19.6
20
IN APRIL 2020, WRF CONDUCTED
a survey of wastewater surveillance
10
activities related to SARS-CoV-2.
Data were collected from 127 individual respondents in the water sector.
0
6.5
6.5
1–49
50–499
The majority of respondents were
collecting samples representing
service areas of 50,000 people or
more; however, smaller service areas
8
Source: WRF 2020a
4.3
500–4,999
5,000–49,999 50,000–499,00
Population Size
>500,000
N/A
Note: Some respondents represent multiple service areas.
Figure 1. Percentage of survey respondents collecting samples from service
areas of different sizes
October–December 2020 • Advances in Water Research
COVID-19
1. Best practices and standard-
along with the working group rec-
Worker and Public Safety (5029) will
ized procedures for the col-
ommendations (WRF 2020b). The
develop a user-friendly model to esti-
lection and storage of waste­-
paper can serve as a resource when
mate worker viral exposure and envi-
water samples.
making decisions about conducting
ronmental viral release from waste-
2. Best practices for the use of
wastewater surveillance and inter-
water treatment operations. This will
tools to identify the genetic sig-
preting and communicating about the
help prepare the wastewater industry
nal of SARS-CoV-2 in wastewa-
resulting data.
for the next epidemic or pandemic
ter samples.
3. Approaches for the use of
Current and Future Research
outbreak of highly infectious viruses
by providing a quantitative basis to
data on the genetic signal of
THOUGH RESEARCH ON SARS-COV-2
SARS-CoV-2 to inform trends
is new, WRF research has focused on
cerns regarding virus persistence, dis-
and estimates of community
pathogens for many years. There-
infection, and potential exposure.
prevalence.
fore, one step WRF took to incorpo-
Measure Pathogens in Wastewater
rate SARS-CoV-2 into its research
(4989), funded by the California
4. Strategies for communicating
to
expand
upon
respond to worker and public con-
the implications of wastewater
was
existing
State Water Resources Control Board
surveillance results with the pub-
pathogen-related projects to include
(SWB), focuses on the development
lic health community, elected
SARS-CoV-2. Environmental Per-
of recommendations for the collec-
officials, wastewater workers,
sistence and Disinfection of the Lassa
tion and analysis of pathogen moni-
and the public.
Virus and SARS-CoV-2 to Protect
toring in raw wastewater to develop
In the two weeks preceding the
Summit, the working groups assessed
the current state of knowledge for
wastewater surveillance and identified
knowledge gaps and research needs.
During the Summit Opening Session,
held on April 27th, the working groups
introduced the key issues in each of
these areas and shared their initial
progress with the public. Attendees
were invited to submit questions and,
Table 1. Near-term research opportunities to support wastewater
surveillance of SARS-CoV-2
Priority
as they refined their recommendations.
High
Shedding Rate and Genetic Signal Effect of wastewater pre-treatment on genetic signal
High
Dilution and persistence of the genetic signal in the sewer
Shedding Rate and Genetic Signal collection system—targeted integrated study (in well-characterized systems that have good hydraulic models)
High
Risk
Evaluation of potential for infectious virus in wastewater and
generation of aerosols
High
Interpretation of Results
Correlations to clinical data for the assessment of community
prevalence—how to leverage wastewater surveillance to provide
useful data to public health stakeholders
High
Interpretation of Results
Define partnership opportunities and continue collaboration
principles, recommended best practices, and near-term research opportunities in each of the four areas.
Summit participants identified four
Medium Methods
Impact of sample collection method (grab vs. composite,
duration of composite, time of day)
Medium Methods
Distribution of virus (or RNA copies) in liquid and solid phases
Medium Interpretation of Results
How to effectively translate COVID-19 research into pandemic
preparedness and wastewater surveillance for future needs
Low
Methods
Which spike organism to use for quality assurance/quality
control purposes
Low
Methods
Comparative methods review for enveloped viruses—focusing on
the concentration from wastewater matrix
key themes for near-term research
opportunities to accelerate progress
in this work: methods, shedding rate
and genetic signal, interpretation of
results, and risk. Table 1 shows the
research opportunities identified
under each theme.
The working groups also developed
a paper summarizing the expert opinions provided throughout the Summit,
Advances in Water Research • October–December 2020
Intra- and interlaboratory assessments on sampling regimes
and molecular methods
Methods
During the April 30th Closing Session,
the working groups presented guiding
Specific Research Opportunity
High
over the following two days, the working groups considered these questions
Theme
Source: Adapted from WRF 2020b
9
COVID-19
better empirical data on patho-
high-priority opportunities identi-
Wastewater sampling (Figure 2)
gen concentrations and variability.
fied during the Summit: Interlabo-
and analysis began on August 17th,
SARS-CoV-2 has been added to the
ratory and Methods Assessment of
and was conducted through late-
list of pathogens of concern for this
the SARS-CoV-2 Genetic Signal in
September 2020. The results of
project, and the research team is
Wastewater (5089) and Understand-
this project, which WRF anticipates
preparing to analyze SARS-CoV-2
ing the Factors That Affect the Detec-
publishing in late 2020, will pro-
in samples archived since Novem-
tion and Variability of SARS-CoV-2 in
vide much-needed information on
ber 2019, along with current and
Wastewater (5093).
preferred methods to be used for
future samples.
Methods
performing analyses for wastewater
SARs-CoV-2 has also been added
Assessment of the SARS-CoV-2
Interlaboratory
and
surveillance studies and understand-
to the list of pathogens of concern for
Genetic Signal in Wastewater will
ing the limits of detection of existing
Collecting Pathogens in Wastewater
provide an assessment of the reli-
methods. In addition to WRF funds,
During Outbreaks (4990), which is
ability and repeatability of labo-
the Bill & Melinda Gates Founda-
determining the feasibility of measur-
ratory methods currently being
tion contributed funding to support
ing pathogen concentrations in Cal-
used to test for the genetic signal
this project.
ifornia wastewater as early warning
of SARS-CoV-2 in untreated waste-
Understanding the Factors That
during community outbreak events.
water. Over 60 laboratories volun-
Affect the Detection and Variabil-
This research effort, also funded by
teered to participate in this proj-
ity of SARS-CoV-2 in Wastewater,
the SWB, involves in-depth litera-
ect. The research team ultimately
also co-funded by the Bill & Melinda
ture reviews of sewage monitoring
selected half of these laboratories
Gates Foundation, will develop an
studies and of seasonal and spatial
to answer four key questions:
approach to understand the sample
trends of enteric pathogen outbreaks
in California.
WRF has also initiated two new
research projects based on the
•
Which laboratory methods are
design factors that affect the detec-
best suited for producing reli-
tion, variability, and dynamic range
able quantitative genetic signals
of SARS-CoV-2 genes in wastewater,
for SARS-CoV-2?
which is crucial for the interpretation
• To what extent
are laboratories
lance. This research will encompass
able to reproduce
a range of scales by conducting a
sample results by
sampling and analytical program
following docu-
in different locations within well-
mented quality
characterized community sewer-
assurance/qual-
sheds. The results of this project,
ity control (QA/
which will be available in October
QC) procedures?
2021, will include a framework with
• Which
steps
specific recommendations for sam-
within a given
ple design to enable implementa-
method are most
tion of wastewater surveillance at
critical to ensure
three scales: large urban sewersheds,
accuracy
and
precision?
• What is the limit
of detection for
the recovery of a
Figure 2. Wastewater sampling
10
of results from wastewater surveil-
medium-sized regional sewersheds
with small bore sewers, and small
regional systems.
Next Steps
genetic signal for
MOVING FORWARD, WRF PLANS
SARS-CoV-2 in
to fund additional research related
wastewater, and
to wastewater surveillance. For
how does it vary
example, the goals and approach
across the avail-
are currently being developed for
able methods?
the project, Impact of Storage and
October–December 2020 • Advances in Water Research
COVID-19 • INTELLIGENT WATER NETWORKS
Pre-Treatment Methods on Signal
Strength of SARS-CoV-2 Genetic
References
Signal in Wastewater. WRF will con-
WRF (The Water Research Foundation). 2020a. “Virtual International
tinue to gather key information from
Water Research Summit on Environmental Surveillance of COVID-19
experts in the fields of infectious
Indicators in Sewersheds—Opening Session.” April 27, 2020. https://
disease control, virology, water engi-
www.waterrf.org/event/water-research-foundations-virtual-international-
neering, outbreak epidemiology, and
emergency response, and provide
water-research-summit-environmental.
———. 2020b. Wastewater Surveillance of the COVID-19 Genetic Signal in
resources and learning opportunities
Sewersheds: Recommendations from Global Experts. Accessed July 27,
to keep the water sector up-to-date
2020. https://www.waterrf.org/sites/default/files/file/2020-06/COVID19_SummitHandout-v3b.pdf.
on these key topics.
More information related to WRF’s
COVID-19 work is available on the
———. 2020c. “COVID-19 Guidance and Resources.” Accessed August 3,
2020. https://www.waterrf.org/covid-19-guidance-and-resources.
WRF website (WRF 2020c).
Intelligent Water Networks
I
(4714)
ntelligent Water Networks Summit gatheredinforma-
intelligent water utility maturity model framework was
tion about experiences with intelligent water networks,
developed to assess a utility’s technological maturity
and facilitated the distribution of this information to
and support the development of strategies, budgets, and
interested organizations. Three regional workshops were
implementation plans for improving the utility’s efficiency
held across the United States, followed by a summit where
and customer service. A maturity model tool was also
water utilities presented case studies addressing topics
developed to assist utilities in conducting self-assessments
such as managing wastewater overflows, non-revenue
using the maturity model framework. A recording of the
water reduction, water quality monitoring, and source
August 2020 webcast on this project is available for view-
water monitoring using standalone vendor solutions. An
ing on the WRF website.
Utility
UNITS >>>
FUNCTIONS >>>
Water
Operations
Source Water
Management
Wastewater
Operations
Support Systems
Collection System
Operations
IT Systems
Water Treatment
Plant Operations
Wastewater Treatment
Plant Operations
Finance
Distribution
System Operations
Disposal/Receiving
Water Management
Human Resources
Maintenance
Maintenance
Customer Service
Engineering
Major operational units and their typical functions
Advances in Water Research • October–December 2020
11
INNOVATION in ACTION
Q&A with Aisha Niang
with a utility that was also under
In my spare time, I’m an avid trav-
a consent decree, learn about an
eler and photographer. I’ve traveled to
in-depth approach to community out-
more than 26 countries and have vol-
reach, gain insight into staffing needs,
unteered on service projects in Mexico,
and recognize the sheer magnitude
Puerto Rico, the Bahamas, and Peru.
of what Houston Water is going to
T
he
Scholarship
embark on. The lessons learned gave
What challenges has Houston Water
invaluable insight from the host utili-
faced that made you pursue a SEE
ties, and the knowledge, experience,
IT scholarship? Due to extensive
Exchange and relationships gained because of
flooding of treatment facilities and
Experience for Innovation &
this trip will be utilized as Houston
numerous historic storm events,
Technology (SEE IT), a LIFT
Water moves forward.
Houston Water is in the initial plan-
initiative guided by The Water
Aisha Niang is the Assistant Direc-
ning and design stages for consoli-
Research Foundation, the Water
tor for Wastewater Operations
dation and flow diversion projects for
Environment Federation, and the
at Houston Water, where she has
various WRRFs.
National Association of Clean Water
worked for 12 years. She oversees the
With a wastewater system that is
Agencies, provides scholarships for
day-to-day operations of Houston’s
comprised of 39 WRRFs, 383 lift sta-
utility personnel to visit other utili-
WRRFs and lift stations, which col-
tions, and 6,200 miles of collection
ties with innovations of interest and
lect and treat wastewater for approx-
lines, it was decided to reduce certain
share experiences with their peers.
imately 2.2 million customers. Aisha
assets and expand others to accom-
Innovations can include new technol-
manages plant optimization, mainte-
modate an increase in flow. Houston
ogies and processes, but also novel
nance, electrical, odor control, bio-
Water is also using the tunneling sys-
approaches to service, operations,
solids, residuals handling, and service
tems for the elimination of SSOs by
and finance. SEE IT provides hands-on
contacts. Following is a summary of
lowering capacity issues and stabiliz-
interaction and gives participants the
Aisha’s thoughts on her experience
ing rising costs via control of oper-
perspective and information needed
with SEE IT.
ations and maintenance (O&M) and
to accelerate adoption of innovations
at their own facilities.
capital expenditures.
Can you tell me more about yourself?
Houston Water, a 2019 SEE IT par-
I began my career in the water indus-
What were the biggest benefits of
ticipant, is in the initial planning and
try as a process engineer for DC Water
being able to visit the various facil-
design stages for consolidation and
at their Blue Plains facility. I then took
ities and meet the practitioners in
flow diversion projects for their water
a position as an operations consul-
person? It made sense to apply for
resource recovery facilities (WRRFs).
tant in New York City for a $4 billion
the SEE IT scholarship to be able to
These projects will reduce plant facil-
expansion project. I received my Bach-
travel and have in-person exchanges
ities from 39 to 31, as well as mini-
elor of Science degree
mize the number of lift stations that
in
are maintained and operated. Hous-
from Howard University,
ton Water believes that tunneling is
and Master of Science
the best option to eliminate sanitary
degree in Civil Engineer-
sewer overflows (SSOs).
ing from Catholic Uni-
Civil
Engineering
The SEE IT field visits to DC Water,
versity. I am a licensed
Seattle Public Utilities, and Panama
Professional Engineer
allowed Houston staff, including Aisha
in Texas and hold dual
Niang, to view different phases of
licensure as a water and
tunneling projects, have an exchange
wastewater operator.
12
October–December 2020 • Advances in Water Research
SEE IT
with utilities that have already tra-
Have any of those relationships con-
create stronger relationships with
versed that path that Houston Water
tinued after your trip? Various rela-
other utilities.
was going to walk on. To be able to
tionships have formed from Houston
stand in construction sites and expe-
Water’s trips to Seattle Public Utilities
Since your trips, has Houston Water
rience their sheer magnitude, visit
and DC Water. Conference calls were
started implementing any of the
neighborhoods that are in the plan-
held to further discuss community
technologies you saw? Houston Pub-
ning phase for tunnel implementation,
engagement, outreach approaches,
lic Works is well underway with the
and to see the community impacts is
lessons learned, and community
planning and design phases for four
not something that you can just read
involvement for tunneling projects.
to five tunneling projects to improve
about—you should SEE IT in person.
An outlier relationship also formed
our wastewater system. It is an excit-
Close collaboration along with the
with regard to asset management
ing time for Houston and a monumen-
field trips sped up the learning, adop-
and hydraulic modeling. The SEE IT
tal one for Houston Water that we
tion, and implementation of tunnel
scholarship afforded the ability to
enter into with confidence because
innovations. The LIFT SEE IT exchange
of our participation in SEE IT.
provided a foundation to pave the
way to avoid project setbacks that
other utilities have encountered.
What were some highlights and takeaways from your trips? The SEE IT
trips allowed us to:
•
Gain insight into how the delivery methods began and evolved.
The trips provided ideas without creating a whole new
deliv­ery method.
•
Reinforce Houston Public Works’
organizational structure by comparing it to other municipalities.
•
Learn about the different methods utilized to deliver major
projects within deadlines.
•
Understand the many aspects
an undertaking of this magnitude will take—from public relations to organization to logistics.
•
Obtain invaluable resources and
vital tips on how to engage with
the community for a large-scale
project like tunneling.
•
Gain an awareness of the unforeseen hurdles that were faced,
which provided us with a broader
perspective of the significant
impacts of a tunneling project.
•
Develop
more
mindfulness
regarding safety for projects of
this size.
Advances in Water Research • October–December 2020
13
Biofiltration
Biofiltration:
30 Years of Research and Guidance
14
October–December 2020 • Advances in Water Research
Biofiltration’s potential savings over costly,
energy-intensive, or waste-generating
advanced treatment techniques are seen
as a significant benefit for utilities.
By H. Grace Jang, The Water Research Foundation;
and Jess Brown, Carollo Engineers
B
iological filtration(biofiltra-
determine biofiltration effectiveness
tion) is the operational prac-
at removing contaminants, define
tice of managing, maintaining,
benefits and communicate them to
and promoting biological activity on
key stakeholders, and provide utility
granular media in a filter to enhance
guidance on optimizing biofiltration.
the removal of organic and inorganic
This research has helped utilities
constituents before treated water is
manage and address the challenge
introduced into the distribution sys-
of optimizing the biological filtration
tem (Brown et al. 2016). Biofiltration
process. WRF’s biofiltration projects
has been used as a part of drinking
funded through the Research Priority
water treatment since the early 1900s.
Program are highlighted in Table 1.
Although biofiltration has a long history of use and holds great promise
as an effective, economic, and sustainable operational practice, it has
Biofiltration Guidance
Manual (4719)
ALTHOUGH THE DRINKING WATER
not been utilized to the full extent
community has gained a greater
possible due to public perception
understanding and knowledge about
problems and resistance to the inten-
biofiltration in recent years, there
tional use of microorganisms within
had not been a single point of ref-
water treatment processes. In recent
erence (i.e., guidance document)
years, however, new stringent regula-
that clearly identified how to design,
tory and technological developments
operate, monitor, and maintain bio-
have encouraged more utilities to
filters to date. The industry experi-
consider biofiltration to treat their
ence indicates that most biofilters
drinking water.
today are still operated on an inci-
WRF’s Biofiltration
Research Area
WRF HAS SUPPORTED consider-
dental basis without a clear strategy for optimizing biological activity or overall biofilter performance.
This is largely due to the absence
able biofiltration-related research
of a consolidated, central reference
over three decades to advance the
for biofiltration design and opera-
science and engineering of biofiltra-
tion. Furthermore, utilities that have
tion. WRF research helped the water
never employed biofiltration need
community to establish baseline
guidance on starting and monitor-
knowledge on the design and oper-
ing biofilters. Recognizing these
ation of biofilters (e.g., filter media
needs, WRF supported Biofiltration
type, filter backwashing). Further-
Guidance Manual for Drinking Water
more, in 2012, WRF launched the
Facilities (Brown et al., forthcoming)
biofiltration research area (formerly
to provide the most comprehensive
known as a focus area, WRF 2019) to
set of practical biofilter design and
15
Biofiltration
operational guidance materials cur-
rate biofilters for drinking water util-
Manual Content
rently available to the drinking water
ities. The project team drew upon
THE INTENT OF THIS MANUAL ISto
industry and to improve the effec-
a cross-section of drinking water
facilitate technology/knowledge trans-
tiveness and maximize the reliability
professionals familiar with this treat-
fer for biofiltration and provide “how-to”
ment approach to ensure that the
guidance in an easy-to-use form. The
guidelines were widely accepted.
manual is organized as follows:
of biofiltration.
Development of the Manual
THIS MANUAL COLLATES FINDINGS
Throughout the development of the
Chapter 1: Background describes a
manual, over 30 professionals rep-
biological filter, gives a historical per-
of previous research and applica-
resenting utilities, regulatory agen-
spective, outlines the theory of the
tions to create a comprehensive
cies, engineering firms, academic
process, and reviews biofilm characteristics and dynamics.
reference that guides the design,
institutions, and manufacturers
operation, monitoring, conversion,
reviewed the guidance manual and
testing, and optimization of rapid
provided feedback.
Chapter 2: Monitoring Tools and
Instrumentation discusses monitoring
Table 1. Six projects funded under WRF’s Research Priority Program
North American Biofiltration Knowledge Base (4459)
This project compiled industry practices into an accessible biofiltration registry and knowledge base, and developed a compendium of research and practical application
information gathered from utilities, universities, manufacturers, and consultants across North America. The purpose of the Knowledge Base is to provide an easy-to-use
resource for utilities wanting to know more about biofiltration or seeking to optimize a system already in operation.
Principal Investigator: Jess Brown, PhD, PE, Carollo Engineers
Biofilter Conversion Guidance Manual (4496)
This project discussed key parameters/aspects associated with the planning, evaluation, implementation, and optimization phases of biofilter conversion and provided
detailed guidance on tasks to be completed at each phase. The guidance manual can improve the likelihood of successful biofilter conversion while helping to minimize
unintended negative consequences. The biofiltration assessment tool can be downloaded: https://www.waterrf.org/resource/biofilter-conversion-assessment-tool
Principal Investigator: Jess Brown, PhD, PE, Carollo Engineers
Optimizing Biofiltration for Various Source Water Quality Conditions (4555)
This project summarized the current state of knowledge and compiled methods currently used to control and optimize biofiltration. It provided guidance with supporting
data for three biofilter optimization strategies (enhancing upstream oxidants, microbial activity, and filter backwashing), focusing on plant optimization that involves only
low-impact, low-cost capital improvements. The balance between treatment objectives and biofilter optimization with plant-specific water quality and treatment goals
was considered for guidance.
Principal Investigator: Chance Lauderdale, PhD, PE, HDR, Inc.
Simultaneous Removal of Multiple Chemical Contaminants Using Biofiltration (4559)
This project collected information and performance data from the literature, as well as pilot- and full-scale studies focusing on key design and operational parameters
and water quality characteristics that may influence the simultaneous removal of multiple contaminants. Based on the information collected during this study, a
multi-contaminant removal matrix was developed, which considered the following key design and operational parameters: media type, biofilter influent water characteristics, pre-oxidation, and empty bed contact time (EBCT). This project can help water utilities achieve maximum simultaneous removal of multiple chemical contaminants
using biofiltration without compromising the existing objectives of the filtration process.
Principal Investigator: Eric Dickenson, PhD, Southern Nevada Water Authority
Guidance Manual for Monitoring Biological Filtration of Drinking Water (4620)
This project evaluated biofiltration process and water quality monitoring tools and discussed their potential benefits for use by utilities. Three strategies for biofiltration
monitoring (biological parameters, natural organic matter and water quality, and filter hydraulics and operation) were assessed, and practical and quantitative guidance on
how to use the tools when they are appropriate, and how to interpret the data, was provided.
Principal Investigator: Jennifer Hooper, PE, CDM Smith Inc.
Biofiltration Guidance Manual for Drinking Water Facilities (4719)
Detailed information is provided throughout this article.
16
October–December 2020 • Advances in Water Research
Biofiltration
tools (filter integrity monitoring,
for converting their conventional filters
design, operation, monitoring, and
hydraulic monitoring, water quality
to biofilters. Chapter 5: Greenfield Bio-
maintenance of biofilters to achieve
monitoring, biological monitoring) and
filtration is for newly proposed biofil-
a multitude of water quality improve-
provides recommendations for biofil-
tration facilities that need guidance on
ments. This manual will facilitate a
tration plants that inform operators of
how to evaluate, design, and operate
broader and more successful imple-
the health of their filters and when to
new biofilters. This chapter covers
mentation of this treatment approach.
take action to prevent a lapse in water
planning, design, and operation of
quality. This chapter also describes
greenfield biofiltration. Several exam-
Additional Pertinent
WRF Projects
how to develop a monitoring strategy.
ples of greenfield biofiltration plants
WRF projects that are relevant to this
and case study facilities are included
THROUGH OTHER RESEARCHpro-
chapter are listed in the sidebar.
to illustrate different applications, pro-
grams, WRF has funded a variety
cess difficulties, and approaches to
of additional projects relevant to
overcome these difficulties.
biofiltration.
There are three types of biofiltration
applications, and the guidance manual
is organized to reflect these applica-
WRF has a number of projects
tions. Chapter 3: Optimizing Exist-
that are relevant to these chapters
ing Biofiltration Plants is for utilities
(see sidebar).
Addressing Emerging Issues:
DBP Formation and Pathogens
that are already operating biofilters
Chapter 6: Operation and Mainte-
SEVERAL WRF PROJECTS EXPLORED
and are focused on improving biofil-
nance summarizes key operational
practical implications of biofiltra-
ter performance. This chapter covers
and maintenance considerations for
tion, including disinfection byprod-
optimization planning and associated
biofiltration, and Chapter 7: Biofiltra-
uct formation and pathogen control.
strategies to deliver improvements
tion Testing addresses eight key ques-
Impact of Filtration Media Type/Age
in overall treatment efficiency and
tions that a well-designed testing plan
on Nitrosamine Precursors (4532; PI:
water quality. Chapter 4: Converting
should answer (Figure 1).
Zia Bukhari, American Water) studied
Conventional Filters to Biofilters is for
This manual also includes 12 appen-
how effectively biofiltration processes
utilities considering converting exist-
dices as supplemental and stand-alone
can remove nitrosamines, specifically
ing filters to biofilters that will need
reference materials (Figure 2).
N-nitrosodimethylamine (NDMA), or
guidance on steps for transitioning to
Water professionals will greatly ben-
their precursors that may ultimately
and enhancing biofiltration. Convert-
efit from this manual as it provides
form nitrosamines due to disinfection
ing conventional filters to biofilters can
clear guidance about planning, testing,
help realize multiple benefits
for drinking water treatment
plants, including improved
organics and contaminant
removal, robust system per-
1. Define Testing Objectives
• What water quality and/or
operational goals am I trying
to achieve?
2. Benchmarking Water Quality
and Treatment Characteristics
• What water quality and
treatment characteristics do
I need to account for?
3. Selecting Testing Scale(s)
• Is desktop evaluation, bench-,
pilot-, demonstration-, or
full-scale testing most
appropriate for my goals?
4. Designing a Desktop Evaluation
• Is biofiltration suitable for
my facility?
• How do I develop a business
case for conducting
biofiltration testing?
5. Designing Bench, Pilot,
or Demonstration Tests
• What should my testing plan
include?
• What equipment do I need?
• How do I assess performance?
6. Overcoming Common Testing
Challenges
• How can I further improve my
testing plan?
7. Understanding Expected
Outcomes
• When should I move to the
next phase of testing?
• When is testing complete?
8. Resource Planning
• What resources do I need to
allocate towards testing to
ensure I meet my goals?
• How do I manage cost?
formance, lower chemical
requirements,
and
lower
operational costs. However,
there are several challenges
that utilities could encounter
while they convert conventional filtration to biofiltration.
Therefore, careful consideration and planning should be
conducted before conversion
implementation. This chapter
helps utilities avoid errors or
omissions in the design and
operation of biofiltration facilities and provides a framework
Source: Brown et al., forthcoming
Figure 1. Eight key testing plan questions
Advances in Water Research • October–December 2020
17
Biofiltration
it is sustainable
Sample Testing Plans (Appendix L)
Biofiltration Terminology (Appendix A)
Full-Scale Biofiltration Plant Compilation
(Appendix K)
Frequently Asked Questions (Appendix B)
Biofiltration Calculations (Appendix C)
Biofilter ConversionCase Studies (Appendix J)
Operations Checklist (Appendix D)
Optimization Decision Trees (Appendix I)
and can be used
to remove pathogens and a variety of organic
compounds.
Demonstration
of High Quality
Drinking Water
Production Using
Multi-Stage
Biofiltration Optimization References (Appendix H)
Troubleshooting Guide (Appendix E)
Ozone
Biologi-
cal Filtration: A
Comparison of
Monitoring Standard Operating Procedures (SOPs)
(Appendix F)
Direct Potable
Tools Compendium (Appendix G)
Reuse
with
Graphic Courtesy of Carollo Engineers
(DPR)
Existing
Indirect
Figure 2. Twelve appendices in the manual
Pota-
ble Reuse (IPR)
(4777; PI: Denise
in drinking water distribution systems.
on the selection for opportunistic
Similar to prior studies, this proj-
pathogens. This project examines
Funk, Brown and Caldwell) evaluated
ect found that NDMA removal data
microbial community structure and
and validated the feasibility and effec-
showed considerable variability, likely
abundance of opportunistic bacterial
tiveness of ozone-BAF treatment in
due to multiple factors (e.g., analytical,
pathogens in full-scale biofilters for
reuse applications. This study found
seasonal, geographic, and operational).
drinking water production. The pre-
that ozone-BAF provided potable
This project suggested that effective
liminary data indicate that multiple
water quality at a 15% blending ratio
NDMA management will require a mul-
variables shape microbial community
(e.g., 15% advanced treated water
tifaceted approach using optimized
structure and richness in granular acti-
and 85% lake water) without the use
coagulant/polymer doses, enhanced
vated carbon (GAC) biofilters and, that
of RO. Another key finding from this
physical separation (e.g., sedimenta-
among those variables, the type of fil-
study was significant cost savings—
tion and empty bed contact times) in
ter underdrain and exposure to chlo-
less than half the cost of full advanced
conjunction with strategic planning for
ramine during filter backwash select
treatment.
selecting the disinfection approach
for non-Tuberculosis Mycobacteria
(specific disinfectant and dosing
location in treatment train). Biological
Filtration: NDMA Control or Source of
Precursors? (4669; PI: Ashley Evans,
populations in the GAC.
Applying Biofiltration in
Reuse Applications
In addition, several projects are
underway to examine the operational
optimization, performance improvement, and treatment requirements for
reuse applications. The WRF projects
Arcadis), evaluated the impact of
TRADITIONALLY, REVERSE OSMOSIS
listed below are related to biofiltration
biofiltration on NDMA precursor con-
(RO)-based treatment has played a
in water reuse.
centrations and provided guidance to
key role in achieving treatment goals
biofiltration facilities to control the for-
in reuse applications. However, it has
Treatment Processes for Potable
mation of NDMA.
some technical challenges such as
Reuse Applications (4776), PI: Zia
Optimizing Filter Operation in an
•
Optimization of Ozone-BAC
Bukhari, American Water
high energy demand, membrane foul•
Evaluation of CEC Removal by
Ozone-Biofiltration Plant to Reduce
ing, and brine disposal. As an alterna-
Selection for Opportunistic Pathogens
tive option, combining ozone with bio-
Ozone/BAF Treatment (4832),
in Drinking Water Production (4743;
logically active filtration (ozone-BAF)
PI: Keel Robinson, Trussell Tech-
PI: Brian Steglitz, City of Ann Arbor)
has drawn attention. This treatment
is studying the impact of disinfectant
approach is already an accepted drink-
exposure during ozone-biofiltration
ing water treatment process because
18
nologies, Inc.
•
Assessing the Impacts of Backwash Practice on Biofiltration
October–December 2020 • Advances in Water Research
Biofiltration
•
Operation and Performance
Summary
(5043), PI: Shih-Chi Weng, Gwin-
THE USE OF BIOFILTRATION HAS ing, and optimizing biofiltration and
implementing, enhancing, monitor-
nett County Water Resources
been an effective, economic, and
enhancing drinking water treatment
Understanding and Improving
sustainable means of providing high-
effectiveness and communication.
Reuse Biofilter Performance
quality water to meet water quality
Producing the comprehensive biofil-
during Transformation from GAC
standards. Over the past 30 years,
tration guidance manual is an excel-
to BAC (5092), PI: Gayathri Ram
WRF has played a significant role in
lent example of WRF’s contribution to
Mohan, Gwinnett County
providing guidance documents for
the biofiltration area and overall water
industry. Beyond drinking water treat-
Relevant WRF Biofiltration Projects
Monitoring Tools:
•
A Monitoring and Control Toolbox for Biological Filtration (4231), PI: Patrick Evans,
CDM Smith Inc.
•
North American Biofiltration Knowledge Base (4459), PI: Jess Brown, Carollo
Engineers
•
ment, interest in ozone-biofiltration
has rapidly expanded to advanced
wastewater treatment and water reuse
applications. WRF will continue working to bridge the gap for biofiltration
application between drinking water
and reuse water.
Full-Scale Engineered Biofiltration Evaluation and Development of a Performance
Tracking Tool (4525), PI: Jennifer Nyfennegger, Carollo Engineers
•
Guidance Manual for Monitoring Biological Filtration of Drinking Water (4620), PI:
Jennifer Hooper, CDM Smith Inc.
Biofiltration Optimization:
•
Engineered Biofiltration for Enhanced Hydraulic and Water Treatment Performance (4215), PI: Jess Brown, Carollo Engineers
•
Optimizing Engineered Biofiltration (4346), PI: Chance Lauderdale, HDR, Inc.
•
Optimizing Biofiltration for Various Source Water Quality Conditions (4555),
PI: Chance Lauderdale, Carollo Engineers
•
Simultaneous Removal of Multiple Chemical Contaminants Using Biofiltration
(4559), PI: Eric Dickenson, Southern Nevada Water Authority
•
Optimizing Biofiltration (BAF) and Integrating BAF Into Existing Treatment (4731),
PI: Jess Brown, Carollo Engineers
•
Optimizing Biofiltration for Improved Manganese Control under Cold-Water Conditions (4749), PI: Ashley Evans, Arcadis
Conversion to Biofiltration:
•
Optimizing Filter Conditions for Improved Manganese Control During Conversion
to Biofiltration (4448), PI: Chance Lauderdale, HDR, Inc.
•
Biofilter Conversion Guidance Manual (4496), PI: Jess Brown, Carollo Engineers
Greenfield Biofiltration:
•
Engineered Biofiltration for Enhanced Hydraulic and Water Treatment Performance (4215), PI: Jess Brown, Carollo Engineers
•
•
References
BROWN, J., G. Upadhyaya, J.
Carter, T. Brown, and C. Lauderdale. 2016. North American
Biofiltration Knowledge Base.
Project 4459. Denver, CO:
Water Research Foundation.
BROWN, J., G. Upadhyaya, J.
Nyfennegger, G. Pope, S.
Bassett, A. Evans, J. Carter, V.
Nystrom, S. Black, C. Alito, C.
Lauderdale, J. Hooper, B.
Finnegan, L. Strom, L. Williams
Stephens, E. Palmer, E. Dickenson, S. Riley, E. Wert, L. Weinrich,
and P. Keenan. Forthcoming.
Biofiltration Guidance Manual
for Drinking Water Facilities.
Project 4719. The Water
Research Foundation.
WRF (The Water Research
Full-Scale Engineered Biofiltration Evaluation and Development of a Performance
Foundation). 2019. “Biofiltra-
Tracking Tool (4525), PI: Jennifer Nyfennegger, Carollo Engineers
tion: Defining Benefits and
North American Biofiltration Knowledge Base (4459), PI: Jess Brown, Carollo
Developing Utility Guidance.”
Engineers
https://www.waterrf.org/news/
•
Biofilter Conversion Guidance Manual (4496), PI: Jess Brown, Carollo Engineers
biofiltration-defining-
•
Optimizing Biofiltration for Various Source Water Quality Conditions (4555),
benefits-and-developing-
PI: Chance Lauderdale, HDR, Inc.
utility-guidance.
Advances in Water Research • October–December 2020
19
Microbiome
Chicago Area
Waterway System
Microbiome Study
20
October–December 2020 • Advances in Water Research
An understanding of the microbial
community structure—the microbiome­—
of urban waters could provide insight
into the human health risks associated
with recreational use of these waters.
By Lola Olabode and Alyse Greenberg, The Water Research Foundation;
Mark Grippo, Argonne National Laboratory; Allison Fore and Geeta Rijal
(Retired), Metropolitan Water Reclamation District of Greater Chicago
A
n integral part of the urban
may pose a risk to humans engaged
water cycle is sewer infra-
in recreational activity (Figure 1).
structure. Treated waste-
Therefore, an understanding of the
water, and to a lesser degree
microbial
stormwater, make up a significant
(microbiome) of urban waters could
community
structure
contribution to total water volume
provide insight into the human health
in the Chicago Area Waterway Sys-
risks associated with recreational use
tem (CAWS). As stormwater and
of these waters. This will also help
wastewater are released into natu-
prioritize actions needed to achieve
ral waterways, traces of human and
and maintain the quality of the water
animal microbiomes are reflected
for primary contact recreation such
in the composition of these waters.
as swimming.
Consequently, the CAWS contains a
Microbial source tracking (MST),
wide range of human- and animal-
also known as microbial source iden-
associated bacteria, some of which
tification, is a DNA-based technology
THE CAWS IS COMPRISED OF WATERWAYS, DAMS, LOCKS, AND PORT
FACILITIES.The Metropolitan Water Reclamation District of Greater Chicago (MWRD) manages the operation of water reclamation facilities to
ensure effective conveyance of treated wastewater, protect water quality,
accommodate commercial and recreational navigation, provide flood
control, and produce hydroelectric energy. The majority of the CAWS is
comprised of man-made canals. The MWRD reversed the Chicago River
in 1900 by constructing the Chicago Sanitary and Ship Canal to take
wastewater away from Lake Michigan to send downstream to address
a public health issue and protect the source of the region’s drinking
water. The success of the Sanitary and Ship Canal led the MWRD to
construct two additional canals, totaling 61.3 miles of canals and waterway improvements. Other parts of the CAWS are natural streams that
have been dredged, straightened, widened, realigned, and otherwise
modified, providing a unique engineered system with a deep history
that has required years of investment and improvement. This work has
protected the drinking water supply, prevented fluvial flooding, and revitalized a once neglected river enlisted to convey sewage into a valued
public amenity and habitat for thriving wildlife. Now with the help of this
groundbreaking study, we gain a closer glimpse into the colorful and
transformative history that is the CAWS.
21
Microbiome
that can be used to determine how
The Terrence J. O’Brien Water Recla-
Study Goals
much of the microbial fecal contam-
mation Plant (O’Brien WRP) in Skokie,
THE OVERALL GOALS OF THISstudy
ination in an aquatic environment is
IL, treats an average of 230 million
were to (1) characterize the microbial
due to humans or other animal spe-
gallons of wastewater per day (mgd),
composition of the CAWS over time
cies. To better understand how bac-
has the capacity to treat 450 mgd,
and space, (2) determine the poten-
terial communities vary with weather
and serves more than 1.3 million peo-
tial sources of bacteria in the CAWS,
and location within the CAWS, this
ple. The Calumet WRP in Chicago, IL,
and (3) determine the impact on
technology, which uses sequencing
has a capacity to treat 430 mgd and
these characteristics following dis-
of molecular DNA, was used to char-
serves a population of more than 1 mil-
infection at the two wastewater rec-
acterize the bacteria found in water
lion people.
lamation plants and the operation of
and sediment at 16 different sites
In 2015, the MWRD implemented
the TCR. Two techniques were used
across the CAWS during a seven-
ultraviolet radiation-based disinfec-
to perform molecular characteriza-
year period (2013–2019). This work
tion technology at the O’Brien WRP
tion of the CAWS microbiome. The
provides the most detailed investiga-
in order to inactivate harmful bacte-
technique called 16S rRNA amplicon
tion of microbial dynamics in an urban
ria and pathogens in effluent released
sequence analysis was used to iden-
waterway ever attempted. The study
into the North Shore Channel and
tify bacterial groups (taxa) present
also helped to determine the impact
North Branch of the Chicago River. At
in the CAWS. The 16S rRNA gene is
of recently implemented upgrades to
the Calumet WRP plant, a chlorination-
necessary for ribosome assembly,
two Metropolitan Water Reclamation
and dechlorination-based disinfection
contains variable sequence regions
District of Greater Chicago (MWRD)
technology was implemented. Fur-
that are specific to different micro-
water resource recovery facilities and
thermore, as part of the Chicago Area
bial species, and can therefore be
stormwater management controls.
Tunnel and Reservoir Plan (TARP) that
used for taxa identification. Shot-
Facility Improvements
and Operations
is designed to intercept the combined
gun metagenomic sequencing was
sewer overflow (CSO) discharges, the
used to assess functional attributes
Thornton Composite Reservoir (TCR)
of the microbial community such
in the Calumet WRP service area
as virulence. Unlike the 16S rRNA
district responsible for treating waste-
became operational in December 2015.
approach, which targets a specific
water and providing stormwater
The TCR provides 7.9 billion gallons of
gene sequence, shotgun metag-
THE MWRD IS A SPECIAL-PURPOSE
management in Cook County, Illinois.
storage to capture combined storm-
enomics sequences genes from a
Wastewater and stormwater from the
water and sewage that would other-
broad array of microbial taxa.
MWRD service area flow to seven
wise have overflowed into the CAWS
Another goal was to develop a
water reclamation plants (WRPs). Two
during storm events, which is then
model that could predict fecal indi-
of the WRPs implemented effluent
eventually pumped to the Calumet
cator bacteria for a given set of
disinfection upgrades in recent years.
WRP for treatment.
environmental conditions. Therefore,
Figure 1. Recreational activities on the CAWS
22
October–December 2020 • Advances in Water Research
Microbiome
several modeling approaches were
reduction in sewage indicator bac-
detection to include microorganisms
also tested to predict fecal indica-
teria can be attributed to the imple-
and viruses that are not detected
tor bacteria concentrations at any
mentation of the disinfection process
by traditional approaches. In this
point along the CAWS under various
at the O’Brien WRP. Furthermore, the
study, 16S rRNA amplicon and shot-
seasonal and hydrologic conditions
reduction in sewage-associated bac-
gun metagenomic sequencing pro-
and estimate the probability that
teria following the implementation
vided a detailed characterization and
fecal coliform concentrations will
exceed regulatory standards.
Results
MOLECULAR CHARACTERIZATION of bacteria indicates that
the CAWS bacterial community
is diverse, with more than 30,000
species of bacteria in the water and
sediment alone. The majority of
microbial diversity in CAWS water
samples can be largely attributed
to effluent, sewage, CAWS sediment, river water, and fish mucus
samples, with animal- or human-
improved understanding of micro-
This is the
most detailed
investigation
of microbial
dynamics
in an urban
waterway
associated feces contribution
bial communities in the CAWS and
how they respond to infrastructure improvements to address
water quality. In addition, molecular methods can identify many
of the sources that contribute to
the diverse microbial community
in the CAWS. These molecular
approaches enhance the utility of
existing water quality assessment
tools by providing better characterization of pathogens and their
virulence profile and increased
understanding of the sources of
microbial communities.
being extremely low. The bacterial
of disinfection and the TCR demon-
Improving the current CAWS fecal
groups (taxa) indicative of effluent
strated by the molecular analysis was
indicator bacteria model should start
and sewage were mostly bacteria
confirmed by the results of monthly
with collecting fecal coliform samples
whose abundance is increased by
fecal coliform analysis determined by
50 times per water quality sampling
the wastewater treatment process
the conventional coliform plate count
site per month from March to Octo-
and sewage infrastructure, and are
method. These results suggest that
ber. In addition, the model should be
not considered to be human patho-
the disinfection processes imple-
“retrained“ and “retested” on an annual
gens. Across the CAWS, there was
mented at the O’Brien and Calumet
basis, thereby taking into account
an increase in sewage indicator
WRPs were effective at reducing dis-
important, incremental changes in
bacteria during the wet weather
charges of fecal and sewage indica-
the system such as land use/land
events, irrespective of whether
tor bacteria into the CAWS.
cover and structural changes in the
CSOs occurred during these events.
None of the modeling approaches
hydraulic system (e.g., TARP). How-
Compared to the pre-disinfection
provided satisfactory accuracy in
ever, these improvements, particularly
period (2013–2015), in the four
predicting fecal coliform levels. This
an increase in monitoring frequency,
years post-disinfection (2016–2019)
is likely because the monthly sam-
will be difficult to achieve given the
there was a sequential decrease of
pling frequency of the fecal coliform
effort required.
sewage and fecal indicator bacte-
data available was not sufficient for
The study demonstrated the util-
ria in both the treated WRP efflu-
model training. However, this effort
ity of microbiome monitoring for
ent and river water samples col-
produced an operational model for
assessing improvements to water
lected downstream of the Calumet
predicting fecal coliform density and
quality and provides a deeper under-
and O’Brien WRPs. In the Calumet
regulatory exceedance probability.
region, the decrease in the sewage
indicator bacteria was likely related
to disinfection at Calumet WRP and
Challenges, Lessons
Learned, and Benefits
standing of the microbial makeup of
a unique waterway system. It also
gives an indication of the potential of water quality improvements.
the decrease in CSO events follow-
WHILE CONVENTIONAL COLIFORM
While this study focused on assess-
ing implementation of the TCR. In
plate counting is still valuable, the
ing improvements to treatment
the northern area of the CAWS, the
use of DNA sequencing can broaden
plants, other improvement efforts,
Advances in Water Research • October–December 2020
23
Microbiome • GREENHOUSE GASES • BIOFUEL
such as increasing riparian habitat,
more than 120 years ago. The results
infection of rates of pathogens like
could also be assessed using such
of this unprecedented research can
SARS-CoV-2 has been demonstrated
genetic monitoring approaches. As
be used to guide development of
in several cities. Sampling the sewer
the MWRD continues to expand
standards and implementation of
system in multiple locations in the
TARP and invest in new water rec-
actions to improve water quality for
city is a cost-effective alternative to
lamation plant technologies, results
primary contact recreation in the
tracking infections by testing individ-
of this study can serve as a roadmap
CAWS and a greater understanding
uals. Other public health issues, such
to achieving potential water quality
for all waterways.
as the presence of antibiotic resis-
improvements not envisioned since
In addition, the utility of using
tant bacteria, can also be effectively
the MWRD engineered the rever-
microbiome monitoring at treat-
monitored using genetic monitor-
sal of the flow of the Chicago River
ment plants to track the spread and
ing methods.
Modeling Collection System
Greenhouse Gases (4885)
I
t is important for wastewater utilities to understand and
production of methane in sewers and its potential contri-
address the physical, chemical, and biological influences
bution to the overall GHG emissions inventory.
in the sewer within a single, comprehensive model. Con-
veyance Asset Prediction System (CAPS): Modeling and
Mitigation developed a tool and techniques for improving
the assessment of, and proactive planning for, corrosion,
odor, and greenhouse gas (GHG) evolution in sewer collection systems. By using these resources to holistically
evaluate collection systems, utilities can make informed
decisions, adopt mitigation methods, and implement
capital programs in a coordinated, prioritized, sciencebased approach. In addition, the project addressed the
Experimental setup for the measurement of dissolved gas
Transportation Biofuel Development
H
ydrothermal
liquefaction without drying, and eventually be
renewable, cost-effective feedstock
quickly converts the waste
used for finished fuels. Building upon
for biocrude production as a precursor
solids from water resource
previous research, including projects
for liquid transportation biofuels. The
recovery facilities (WRRFs) into a
supported by WRF, the Pacific North-
results of the study were published in
biocrude intermediate that can be
west National Laboratory conducted
an open access paper in the Journal of
used to develop a variety of liquid
a study investigating opportunities
Environmental Management, and are
fuels. A key advantage of this pro-
to improve energy recovery at U.S.
available at https://doi.org/10.1016/
cess is that wet organic materials can
WRRFs to transform underutilized
j.jenvman.2020.110852.
be converted into oil, gas, or both
municipal wastewater solids into a
24
October–December 2020 • Advances in Water Research
Natural Assets
Management of
Natural Assets
The condition and performance of natural assets are essential to a utility’s
ability to cost effectively and reliably deliver safe drinking water and/or
clean water and stormwater management services to its customers.
By Bob Raucher, Raucher LLC; Kurt Vause, StreamlineAM LLC; and Maureen Hodgins, The Water Research Foundation
N
Aligning with Broader Utility
Programs and Objectives
atural assets—includingfor-
to managing natural assets, which
ested watersheds, aquifer sys-
often are owned, managed, and/or
tems, wetlands, and other nat-
accessed by entities other than the
THE AM FRAMEWORK AND guid-
ural features—provide a wide range of
utility. Asset Management Frame-
ance provide a clear, step-by-step
highly valuable services to water utili-
work for Forested and Natural Assets
process to help utility professionals
ties, including contributions to source
(Raucher et al. 2020), provides a
systematically identify, assess, prior-
water quality, moderating runoff and
framework, and associated practical
itize, and manage risks associated
floods, and groundwater recharge.
guidance, for how utility professionals
with natural assets. The approach
The loss or degradation of these natu-
can apply the principles and tools of
helps identify and assess potential
ral assets can reduce the levels of ser-
advanced asset management (AM)
changes in the quality and quantity
vice (LOS) provided, increase costs,
practices to the natural systems that
of natural systems and the associated
and pose significant additional risks
are critical to meeting a utility’s mis-
services upon which a utility relies. It
for a utility.
sion and strategic objectives. Several
also contains illustrative examples
Because natural assets provide
leading utilities have established AM
and cross references to several exist-
many important core services and
practices for both built and natu-
ing tools, frameworks, and standards
associated beneficial values, they
ral systems, and other utilities have
related to source water hazards. By
must be well managed. Like the
begun the process of applying AM
adopting an AM framework, the guid-
built assets upon which a utility
practices to their natural assets. While
ance will help bring a utility’s natural
depends, natural assets require sys-
the report focuses on drinking water
assets into better alignment with the
tematic attention and management
utilities, the same principles and prac-
approach and strategic objectives
to ensure that they deliver the types
tices may also be applied to natural
applied by many utilities to their
of services that the utility relies on.
assets supporting clean water, water
built systems. For example, applying
However, there are several challenges
reuse, and stormwater agencies.
an AM framework can place source
Advances in Water Research • October–December 2020
25
Natural Assets
water programs on equal footing
deliver high-quality, safe, and afford-
is recommended, starting with
with pipe renewal and related risk
able water to their customers.
(1) an initial screening/reconnais-
management, sustainability, and
The AM framework for natural
sance phase to make a stream-
resilience enhancement programs.
assets (Figure 1) is based on, and
lined tour around the AM wheel;
This commonality across utility activ-
adapted from, the built asset version
followed by (2) a more in-depth
ities arises because these varied
developed by American Water Works
and focused application of the
programs all typically apply a similar
Association (Campanella et al. 2016),
AM framework; and ultimately,
process, with a focus on meeting the
the U.S. Environmental Protection
(3) engaging in a cycle of review
utility’s strategic objectives in a sys-
Agency, The Water Research Founda-
and continuous improvement.
tematic, risk-based, prioritized, and
tion, and the Institute of Public Works
For each step within the AM frame-
cost-effective manner.
Engineering Australia.
Applying the AM Framework
and Guidance
work, Part 2 of the guidance provides
The report consists of two parts:
•
both the technical basis and approach,
Part 1 provides the AM Frame-
as well as the process that will facili-
work for Natural Assets, includ-
tate implementation of the AM frame-
THE FRAMEWORK AND GUIDANCE
ing background information on
work. Also included throughout are
provided in Raucher et al. (2020) are
natural assets and asset man-
checklists, case study illustrations,
intended for water utility profession-
agement, as well as an overview
clear definitions of key terms, and
als and other individuals looking to
offering a succinct introduction
other practical information to help
apply an AM approach to the natural
to the concepts and content,
users apply the AM framework to the
assets that provide critical services
using a Q&A format.
natural assets relevant to their utilities.
and value to their utility. The report
•
Part 2 provides guidance for
describes an AM framework and pro-
applying the AM framework and
vides practical step-by-step guid-
associated practices to natural
ance for how an AM approach may
assets, with a series of chapters
Key Services and Values
Provided, and Risks Faced
SUSTAINABILITY AND EFFICIENCY
be applied in a pragmatic fashion to
that each address a step in the
require that water utilities recognize
forested watersheds, wetlands, and
multi-step AM process depicted
and prudently manage all of their crit-
other natural assets that support the
in Figure 1. A practical, itera-
ical assets—including natural capital—
ability of water agencies to reliably
tive implementation process
as well as built infrastructure and the
2. Describe the Current State of Natural Assets
• Which natural assetsare important for utility performance?
• Who owns those natural assets?
• What is the current condition of those assets?
• Are there threats to the future conditions of those assets?
7. Sustain Naural Asset Management
• How to promote continuous improvement?
• How to practice effective communication?
6. Create a Long-Term Funding Strategy
• Can the utility capture spending on natural assets
through rates?
• Can external funds be leveraged through
partnerships?
• Can investments be made through the capital budget
(e.g., debt financed)?
1. Tap Natural Asset
Management Facilitators
• Leadership commitment
• Align with utility mission and
strategic objectives
• Integrate with knowledge
management, training, and
technology systems
5. Identify Capital Investment and
Maintenance Opportunities
• Are there feasible acquisition, conservation
easement, or restoration options?
• Are there long-term maintenance or enhancement
options?
• What are partnerships that might be required to
execute these?
3. Determine Desired Level of Service (LOS)
• For core business goals, how do natural assets affect
performance? And what LOS from the asset is required
to maintain or improve that performance?
• For other strategic goals, what LOS will meet
community expectations and regulatory requirements?
For natural assets in particular, there is an
interrelationship between condition assessment,
LOS, and risk assessment. It may require an iterative
approach for these three steps.
4. Assess Business Risks Associated With Natural Assets
• How can natural assets degrade and fail to deliver desired levels
of service? What is the likelihood of degredation?
• What are the potential consequences of degraded LOS and the
utility’s vulnerability to reduced performance?
Source: Adapted from Campanella et al. 2016
Figure 1. The Natural Asset Management Wheel
26
October–December 2020 • Advances in Water Research
Natural Assets
utility’s human capital. The framework
watershed, which may impose utility
the project report, is a systematic and
and guidance strengthen a water util-
costs amounting to tens of millions
comprehensive approach for:
ity’s capacity to account for, invest in,
of dollars to address resulting water
1. Creating a useful inventory
and better manage its natural assets.
quality impacts, reservoir sedimen-
of assets, and assessing their
The approach examines the chal-
tation, and other damages. A utility
lenges and opportunities for includ-
supplied by a forested watershed
2. Defining the desired levels of
ing natural assets alongside built
needs to recognize the risks and
service from the assets to meet
infrastructure in how water utilities:
consider how to reduce the likelihood
utility strategic objectives;
•
condition;
Develop and apply business
and/or consequences of such a risk
3. Assessing the risk that the asset
case evaluations,
event. Risk management might thus
may degrade, or fail, and thus not
entail actively supporting efforts to
deliver the target LOS required
better manage forest lands in ways
to meet the utility’s higher-order
•
Assess and manage risks,
•
Plan
for
robustness
and
resilience,
that reduce the likelihood, intensity,
•
Value and leverage their assets,
and spatial extent of potential wild-
4. Applying a risk management-
strategic objectives;
•
Prioritize and manage capital
fires, and that manage the sediment
based approach to identifying
improvement programs and
and debris loads that result after such
potential capital investments
operation and management
events. The objective for the utility is
and/or maintenance expendi-
budgets,
to establish the level and quality of
tures for at-risk assets, to miti-
•
Gain access to financing,
the services to be provided by the
gate risks to the asset’s ability
•
Recover costs through rates
forested watershed, then monitor and
to meet target LOS;
•
and other potential revenue
manage performance in the face of
sources, and
the risks that apply to that asset.
Communicate and collaborate
with outside parties (including
watershed partners).
Natural assets, along with the util-
5. Conducting business case evaluations of the risk mitigation
options to ensure they warrant
Drawing on the Maturing
Practice of AM
investment of utility resources;
6. Implementing the selected risk
THE GUIDANCE DRAWS FROM THE
mitigation options;
ity’s other key assets, are subject to
rich field of AM as increasingly applied
7. Monitoring asset conditions and
potential changes that pose busi-
by water utilities to pipelines, treat-
performance periodically to
ness risks to the utility. For example,
ment plants, and other built systems.
ensure the risk mitigation invest-
watersheds may be subject to devel-
The objective is to draw on the same
ment is performing as planned;
opment, wildfires, flooding, and other
principles and practices that are gain-
events that would significantly alter
ing maturity and broader sector-wide
the level and/or quality of services
application for built systems, and to
tion approach if/as needed to
that flow from those assets. Utilities
apply them to natural assets so that
ensure desired asset conditions
must recognize these risks, and they
a water utility can manage all of the
are attained and performance
need to apply the same principles and
business risks of asset failures on
is meeting target LOS (and
practices of risk management as they
equal footing.
continuing the periodic review
would for a built system (Figure 2).
One example of a risk event is a
and
8. Adjusting
Asset management, as described
risk
mitiga-
process to promote continuous
and applied in the literature and in
high-intensity wildfire in a forested
the
improvement).
Because natural assets can be
managed through capital
investment and/or maintenance activities, the
Identify Assets
Assess Risk
Develop Options
to Mitigate Risk
Create
Long-Term
Funding Plan
principles and methods of
AM can be applied to them.
In other words, natural
assets can be integrated
into AM so that they are
Figure 2. Building up to a long-term risk management and long-term funding plan
Advances in Water Research • October–December 2020
managed alongside built
27
Natural Assets • MANGANESE
assets to best meet a utility’s overarching business goals and strategic
objectives.
The framework and guidance
offer a systematic, step-by-step
approach for incorporating natural
assets into an AM program, building on standard asset management
Manganese Control (4749)
E
xpanding the understanding of the impacts of cold watertemperatures (i.e., below 15°C) on manganese (Mn) control across surface
water biofiltration is critical. The objectives of Optimizing Biofiltration
for Improved Manganese Control under Cold-Water Conditions were to (1)
principles and practices. They also
evaluate the primary causes of decreased dissolved Mn removal across sur-
identify and address specific chal-
face water biofilters during cold-water conditions, and (2) test optimization
lenges of natural assets and those
strategies for improving dissolved Mn removal across surface water biofilters
that may require unique approaches.
during cold-water conditions. The research assessed the impacts of media
proj-
characteristics, influent water quality, shutdowns, and empty bed contact
ect was generously provided by
Co-funding
for
this
time on dissolved Mn removal across biofilters. Overall, this project confirmed
the US Endowment for Forestry
that there is a temperature threshold below which cold-water conditions
and Communities.
decrease dissolved Mn removal across surface water biofilters. It is recommended that utilities operating or considering biofiltration frequently monitor
Mn concentrations across all treatment processes, and if Mn is observed in
the filter influent, evaluate upstream control strategies and/or biofilter design
References
and operating strategies to improve Mn control.
CAMPANELLA, K., C. Hyer, A.
Vanrenterghem Raven, and K.
Vause. 2016. Designing a
Risk-Based Pipeline R&R
Planning Program Using a
Combination of Inspection
and Analytical Approaches.
In Proc. of American Water
Works Association Annual
Conference and Exposition,
June 2016. AWWA.
RAUCHER, R., K. Vause, M.
Lorie, T. Helgeson, and J.
Cassin. 2020. Asset Management Framework for Forested and Natural Assets.
Project 4727. Denver, CO: The
Water Research Foundation.
Biofiltration pilot plant columns
28
October–December 2020 • Advances in Water Research
Trace OrganicS • LEAD
Trace Organic Compounds (4992)
E
valuating Analytical Methods for Detecting non-targeted analysis of unknown contaminants by both
Unknown Chemicals in Recycled Water summarizes
instrumental methods and bioassays, along with the advan-
the current state-of-the-science for analytical meth-
tages and limitations of each approach. The research report
ods used to identify and measure unknown trace organic
includes a research plan to evaluate the effectiveness of
compounds (TOrCs) in recycled water. The researchers
using these strategies for identifying unknown TOrCs, as
propose an integrated framework that includes targeted
well as a communications strategy that can be used by
analysis of known contaminants, as well as semi- and
regulators, managers, and the general public.
Sample preparation methods for determination of TOrCs in aqueous matrices
Method
Target Analytes
Solid phase extraction (SPE), activated carbon
Non-polar, polar organics
SPE, cation exchange, acidic conditions
N-nitrosodimethylamine precursors
SPE, hydrophobic/hydrophilic balance (Oasis HLB)
Pharmaceuticals and personal care products, transformation products (oxybenzone)
SPE, hydrophobic sorbent (e.g., C-18, XAD, HP-20)
Non- and semi-polar organics
Derivatization
Polar, non-volatile organics, disinfection byproducts
Purge and trap extraction
Volatile organic compounds
Azeotropic distillation
Volatile, non-purgeable, water soluble organics
Liquid-liquid extraction
Non- and semi-polar organics
Lead Service Line
Identification (4693)
D
eveloping an accurateinven-
approach has produced low accuracy
and sufficiently sensitive to identify
tory of lead service lines
rates. Exploratory excavation can be
lead pipes buried in soils of various
(LSLs) is a challenge facing
cost-prohibitive without an accurate
types. Additionally, indirect screening
many water utilities. The water sec-
inventory of LSLs. Lead Service Line
techniques used by utilities to gather
tor has relied on indirect methods
Identification Techniques reviewed
information on the likely presence of
that use historical records, such as
the literature and industry practices
LSLs were explored using case stud-
tap cards, to develop inventories of
to identify detection technologies
ies to substantiate the usefulness of
customer locations thought to have
that are fast, portable, economical,
promising approaches.
LSLs. However, in some instances this
user-friendly, minimally invasive,
Advances in Water Research • October–December 2020
29
?
What topics are
important to you
Complete the Advances in Water Research survey
and let us know what you want to read about!
Respond by January 31!
https://bit.ly/3eMo4SZ
Descargar