The original mass, which reduced the tunnel
to just 5% of its capacity, was discovered after nearby residents complained of
being unable to flush their toilets. Had it remained in place, wastewater was
at risk of spurting from manholes throughout the Kingston area of southwest
London, according to Gordon Hailwood, waste contracts supervisor for Thames
Water. As it was, the sheer weight of the fat in the pipes pushed the old brick
sewer down into the soft subsoil, creating the need for major repairs.
The source of the London fat remains under
investigation. “This sewer pipe collects the sewage from across most of
Kingston, so it could be coming from anywhere,” Hailwood reported. The only
thing officials know for sure is that the latest deposit took place in the
weeks following the original discovery.
How did they know? Old, congealed fat is
white, according to Hailwood. But the most recently discovered fat is a
“fresher” shade of yellow, he said.
The most recent discovery is not only adding
to the cost of repairs, it also is raising questions about the success of an
ongoing media campaign to educate residents and businesses on the dangers of
disposing wet wipes and fats, oils, and grease (FOG) into the sewers. Officials
have been creative in choosing approaches to draw the public’s attention to the
problem, from tabloid newspaper-style press releases that graphically describe
the problems associated with flushing nondisperables down the toilet, to a
parody music video, “Can’t Flush This,” which was produced and posted on
) by United
Group (Warrington) the largest water company in the United Kingdom.
Wet wipes and grease: A disastrous combo
You don’t have to live in
London to appreciate the challenge Thames Water now faces. One of the most
challenging — and often baffling — part of any sewer operator’s job is dealing
with the random things that
make their way into a city’s sewer system. Prisoner
toothbrushes (they have a telltale extra-short handle), tools used for breaking
and entering, toys, jewelry, coins, live animals, false teeth, carpeting — all
can wreak havoc with a system’s equipment, costing cities tens of thousands of
dollars in added maintenance costs a year.
problems created by the improper disposal of FOG and one-time-use premoistened
wipes are eclipsing them all,
many operators said.
No longer reserved for babies’
bottoms, wipes have gained widespread use by travelers, soldiers, hikers, and
others who lack ready access to fresh water or are looking for a convenient way
to clean a dirty surface. Specialty wipes have been created for everyone from
pet owners to those suffering from hemorrhoids.
“These wipes are not degradable like toilet
paper, and that is the problem,” said Michael Seay, an environmental specialist
for the City of Dallas (Texas) Water Utilities. “They foul up pumps and cause
blockage in the collection systems, increasing the cost of operations.” Put
them in proximity to FOG, and the problems snowball like a congealed lump of
lard in a sewer.
To help change consumer habits, t
National Association of Clean Water Agencies and other groups are working with
the fabric industry to adjust the directions on products with the “flushable”
Water Environment Federation (Alexandria, Va.) has created a webcast on the
topic of nondispersables and devoted a session to the issue at last month’s
WEFTEC® conference in Chicago.
Could it happen
The question is, could a titanic fatberg like
the one in London form in a sewer tunnel on this side of the Atlantic?
Yes, said Frank Dick, industrial pretreatment
coordinator for the city of Vancouver, Wash. “All of the characteristics of the
London sewer where the fatberg resided exist in larger cities in the U.S.,” he
said. In addition to FOG and wipes, these include the presence of large, old
concrete pipes with “sags” or “bellies,” and cool — approximately 15.5ºC (60ºF)
— sewer water.
“The 15-ton berg is particularly impressive,
but many of us have seen what we call ‘grease balls,’” Dick said.
The key is to locate and remove these grease
balls before they have a chance to “mate” with the growing number of wipes in
the system, said Nick Arhontes, director of Facilities Support Services for the
Orange County Sanitation District (Fountain Valley, Calif.). “If [cities] are
doing good condition assessments, and spotting grease and debris build-ups
early, they will minimize the potential for a similar problem occurring in
their system,” he said.
The city of Vancouver, British Columbia, went
even a step further. To track how wet wipes moved through their system,
officials recently had sample wipes dyed in different bright colors to see if
they would end in the headworks screens at their treatment plant.
In case there’s any doubt, yes, they did.
It’s like the song says: “Can’t flush this.”
— Mary Bufe,
the green frontier
The world’s largest algae and wastewater project in Spain
is showing positive results
project in Southern Spain, billed as the world’s largest project to convert
algae into clean energy using wastewater, is starting to bear fruit of an
autotrophic kind. The algae crop is producing “outstanding results,” according
to a press release by Aqualia (Madrid), a water company that is helping to fund
the project. (The European Union and local government of the town of Chiclana
are two of the other five partners providing funding.)
The “biomass obtained shows a particularly high energy
potential relative to its digestibility level, with a methane production
capacity of around 200–300 litres of gas per kilogram of biomass processed by
anaerobic digestion,” according to the release. “The microalgae also allow the
purification of wastewater to a high standard.”
The project is regarded as the largest of its kind
because it will encompass 10 ha of cultivation during its final phase. “In New
Mexico, there is a 6-hectare biofuel production site — but this uses artificial
fertilizer not waste nutrients,” according to the release. “Various other
installations around 10 hectares do exist but use food-based crops.”
Responding to a global need
Frank Rogalla, director of Innovation and Technology
at Aqualia and project coordinator, said his team was well aware that algae
need both optimal temperature and sunshine to grow, which is why they chose the
southern tip of Spain for the location of the project. They are using municipal
wastewater from a water resource recovery facility in Chiclana to grow the
crop, Rogalla said.
“The preliminary work is to define the best source of
wastewater (primary, secondary, after anaerobic pretreatment) in order to
achieve the highest algae productivity, and the best effluent quality,
depending on climatic conditions,” Rogalla said.
The team has made a few other discoveries through the
course of the project, namely how to best optimize the energy balance for pond
mixing, carbon dioxide injection, and algae harvesting with dissolved air
floatation, Rogalla said.
The goal is to produce enough biofuel by 2016 to power
200 vehicles, according to the news release. By the time the project reaches
this phase, the biogas will be used to power public buses and garbage trucks in
the region of Cadiz.
This goal falls in line with the European Union (EU)
goal for all EU countries to use 10% biofuels in transportation, Rogalla said.
He also noted EU’s parallel goal that “calls for the 20% cut in greenhouse gas
emissions compared to the 1990 levels by 2020, a 20% increase in the use of
renewable energy by 2020, and a 20% cut in energy consumption through improved
energy efficiency by 2020.”
Rogalla said that after 2 years of preliminary
experiments with six 32-m2 areas of cultures, “we are now building
the next step, which is a prototype of [two 500-m2 areas] or a total
of 10,000 ft2 of culture, including the whole value chain to
transform wastewater into bioenergy via algae digestion and biogas production.”
He said that once “the prototype phase has confirmed the main design
parameters, we will launch the ultimate demo phase to reach the goal, a 10-ha
[25-ac] algae farm fed by around 5000 m3/d [1.3 mgd] of wastewater.”
— LaShell Stratton-Childers,
use wastewater to find the source of diseases and try to prevent the spread of
years, scientists have been analyzing microconstituents in wastewater to get a
better understanding of the behaviors of a population, specifically drug use
rates. Some argue that conducting this research serves an important purpose
“Estimating the scale of community drug use
is important in assessing the needs for law enforcement, public health, and
education,” said Kevin Thomas, research manager of ecotoxicology and risk
assessment at NIVA in Oslo, Norway.
Thomas and his team tested in 2010 for the
presence of different biomarkers in wastewater from a few Norwegian water
resource recovery facilities to analyze the use of cocaine, amphetamines, and
MDMA (ecstasy) in surrounding cities. They were able to determine trends in
usage both regionally and monthly.
Now researchers have taken the next step and
are using wastewater to serve an even larger social purpose. They are using
effluent to detect the presence of diseases in a population and try to thwart
future outbreaks and epidemics. Though Israel hasn’t experienced a case of
polio since 1988, the World Health Organization (WHO; Geneva) detected the
presence of the polio virus in wastewater samples in the country. This led
Israel to step up vaccinations to prevent an outbreak. Meanwhile, a report
released in August by researchers at the Yale Law School and the Yale School of
Public Health (New Haven, Conn.) alleges that United Nations (U.N.)
peacekeeping forces caused the deadly cholera outbreak in Haiti after the
devastating earthquake on the Caribbean island in 2010. This bacterium entered
the local water supply due to inadequate water and sanitation facilities at a
U.N. base, the report states.
wastewater to try to stymie an outbreak
Between February and August, WHO detected the
same strain of the polio virus in 67 wastewater samples taken from 24 sampling
sites in Israel. The wild poliovirus type 1 (WPV1) also had been isolated “in
stool samples from 27 healthy children (all under the age of nine years) and
one adult, who had been fully immunized for their age as part of ongoing stool
sample survey activities,” according to a WHO Aug. 15 news release. “In
addition to routine acute flaccid paralysis, public health authorities have
expanded the surveillance to all age groups and have increased enterovirus
surveillance and are screening aseptic meningitis cases for polio,” according
to the release.
The virus initially was detected only in
Southern Israel. To try to prevent its expansion, Israel’s Ministry of Health
increased efforts to inoculate children in the southern part of the country
with another weakened live polio vaccine. Across Israel, the vaccination rate
against polio is 94%, according to WHO. The country also had plans to start a
nationwide inoculation campaign in August.
Unfortunately, these efforts to prevent the
spread of the virus outside of the southern region have not been successful.
Although no actual cases of paralytic polio have been reported, WPV1 also had
been detected in the central district as of August. And though in June WHO
initially had assessed the risk of further international spread of the virus
strain from Israel as “low to moderate,” by August, the risk had been increased
to “moderate to high.” WHO explained in the news release that this “risk
assessment reflects evidence of increasing geographic extent of circulation
over a prolonged period of time.”
Trying to find
the source and access accountability
In the report, “Peacekeeping without
Accountability,” researchers allege that the U.N. bears responsibility for the
cholera outbreak in Haiti that has killed more than 8000 people and sickened
more than 600,000, according to a Yale Law School Aug. 6 news release.
According to the report, U.N. peacekeeping troops inadvertently carried the
disease from Nepal to the Haitian town of Méyè. In October 2010, the U.N.
deployed these peacekeeping troops to join the MINUSTAH in Haiti to help with
earthquake relief efforts. Peacekeepers from Nepal, where cholera is endemic,
arrived in Haiti shortly after a major outbreak of the disease occurred in
their home country.
The Méyè base, which was about 40 km from
Port-au-Prince, was just a few meters from a tributary of the Artibonite River,
“the largest river in Haiti and one [of] the country’s main sources of water
for drinking, cooking, and bathing,” according to the report. Sanitation
infrastructure at the base was “haphazardly constructed, and as a result,
sewage from the base contaminated the nearby tributary,” the report states.
“Less than a month after the arrival of the U.N. troops from Nepal, the Haitian
Ministry of Public Health reported the first cases of cholera just downstream
from the MINUSTAH camp.”
The report alleges that “cholera spread as
Haitians drank contaminated water and ate contaminated food; the country’s
already weak and over-burdened sanitary system only exacerbated transmission of
the disease among Haitians. In less than two weeks after the initial cases were
reported, cholera had already spread throughout central Haiti.”
The Yale researchers were able to establish
several key findings that they say prove the MINUSTAH peacekeeping troops
introduced cholera into the country. One of those findings was that “the troops
at the MINUSTAH base were exposed to cholera in Nepal, and their feces
contaminated the water supply near the base,” according to the report. Also,
the outbreak in Haiti is traceable to a single South Asian cholera strain from
Nepal. “No compelling alternative hypothesis of the epidemic’s origins has been
proposed,” the report states.
Because the Yale researchers believe the U.N.
is the cause of this outbreak, they also believe it is the U.N.’s “legal and
moral obligations to remedy this harm,” according to the Aug. 6 news release.
“While the U.N. has played an important role
in the Haitian post-earthquake recovery effort, it has also caused great harm
to hundreds of thousands of Haitians,” said Tassity Johnson, a student at Yale
Law School and one of the authors of the report, in the news release. “The
U.N.’s ongoing unwillingness to hold itself accountable to victims violates its
obligations under international law. Moreover, in failing to lead by example,
the U.N. undercuts its very mission of promoting the rule of law, protecting
human rights, and assisting in the further development of Haiti.”
instrumentation set for growth
instruments can help streamline operations and save on labor costs, but skilled
operators still will be needed
to a recent report from Frost & Sullivan (Mountain View, Calif.), the U.S.
water and wastewater analytical instrumentation market is projected to
experience steady growth in the years to come, reaching $330.7 million in 2018,
up from $275.3 million in 2012, driven mainly by a need to increase
operational efficiency. Continuous analytical instruments increasingly will
replace laboratory instruments due to their reliability, the report found, with
many larger facilities investing in these instruments as a way to increase
analytical efficiency while also reducing operational costs.
Since the economic downturn, municipalities
facing budgetary restrictions have become increasingly interested in adopting
strategies that work to enhance or improve operational efficiency and maximize
staffing without having to hire more personnel, said Eric Meliton,
an energy and environmental industry analyst with Frost &
“By adopting advanced analytical instruments,
utilities can eliminate many of the redundancies associated with laboratory
instruments and actually do more work while using less people, cutting labor
costs without impacting the testing and monitoring that is required for compliance,”
said Meliton. “Long-term, facilities that incorporate continuous automated
instrumentation will be able to capture more data and subsequently utilize that
data faster, all of which contribute to greater efficiency.”
The adoption of analytical instrumentation in
the water and wastewater sectors represents how some utilities are embracing
higher levels of technology and adapting to a landscape that is fast-changing,
Meliton said. “This trend is similar to what has taken place in the energy
sector, with advanced monitoring and smart grid technology, which has helped
greatly improve efficiency, especially on the labor and staffing side,” he
And with advanced instruments coming into
this sector, the role of the operator is likely to change, Meliton said,
creating more demand for operators and technicians who are comfortable with
today’s new technologies.
training is essential
Analytical instrumentation, while promising
in terms of being more cost-effective in the long-term, also carries
implications for the municipal workforce — particularly for operators and staff
charged with managing instruments.
It is important for operators to view
advances in instrumentation as an opportunity to become educated in the trends
taking shape, said Christine Radke, a program manager at the Water Environment
Federation (Alexandria, Va.) specializing in operator matters such
as training and certification.
“Despite the growth in instruments that offer
greater automation, facilities still will need to rely on properly
trained operators and staff who understand the mechanics and use of these
tools,” Radke said. “Analytical instruments might be easier and more
straightforward in use, but operators also still have to know how to read and
work with the data to help optimize operations.”
The utility of the future will not only be
optimized in terms of instrumentation technology, but also in regard to its
operators, staff, and personnel, according to Radke.
Paula Zeller, a senior operator at the Orange
County Sanitation District (Fountain Valley, Calif.) said analytical instruments are helpful in terms
of increasing efficiency and systemizing tasks, but highly trained operators
still will be essential — especially if instruments fail and manual control
needs to be taken.
“In this sense,
operators will still be heavily relied on to provide oversight management. They
must be capable of making changes or important decisions based on key
information,” she said.
Operators also will
play an important role in communicating the different parameters associated
with the technology, Zeller said. “Instruments are programmed to simplify tasks
and make processes more efficient, but many times the problems that arise
require solutions based on human reasoning.”
While investments in automated analytical
instruments that help streamline operations represent one strategy for managing
budgetary decreases, another approach recently developed by a U.S. Geological
Survey (USGS; Reston, Va.) hydrologist offers potential for addressing cutbacks
in spending by enhancing the overall efficiency of an existing network.
According to research by
Jason Fisher with the USGS’s Idaho National Laboratory project office, budget
constraints in water resource management agencies often lead to a reduction in
the number of wells in a monitoring network. Fisher’s management tool works to
determine which wells in a monitoring network add little or no beneficial
information and can thus be removed with the least effect to the
characterization of the system.
Fisher studied two water-level monitoring
networks within the Eastern Snake River Plain aquifer, developing an algorithm
for optimizing an existing monitoring network using an interpolation method to
map the water table. By comparing water-table maps based on measurements from
the existing and reduced networks, he was able to identify sites giving out
“The goal was to be able to maintain the same
level of information with less data, increasing the accuracy of the network,
and freeing up money that could be put to use in a different part of the study,
making it more robust,” he said. “But if water managers are forced to remove
wells from a network, then hopefully they can use this information to make the
best decisions possible.”
Although developed for a groundwater
water-level monitoring network, Fisher said the management tool could be
applied to most networks using environmental sensors or analytical instruments
as long as a spatial component also is present.
Next, Fisher aims to adapt the management
tool to water quality monitoring networks. “And, if the algorithm can be
tweaked to better handle temporal data, then the information that could be
collected would be the same as in a wastewater treatment plant,” he said.