Drinking Water: Challenges and Solutions for the Next Century

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Drinking Water Challenges and Solutions for
theNext Century

• Mark W. LeChevallier, Ph.D.
• Director, Innovation Environmental Stewardship

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American Water is the largest water and
wastewater services provider in North America,
headquartered in Voorhees, NJ. American Water
provide services to approximately 15 million
people in more than 1,600 communities in 32
states and in Ontario, Canada and employs nearly
7,000 water professionals. American Water owns
or operates nearly 400 drinking water systems and
300 wastewater facilities. We treat and deliver
over a billion gallons of water daily The
company conducts over one million water quality
tests each year for over 100 regulated
parameters, and up to 50 types of water-related
tests each day.
www.amwater.com
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1. Climate Change

• Changing weather patterns
• Higher surface air temperatures
• Melting of polar ice caps
• Longer, more frequent droughts
• Shorter, higher intensity rainy seasons
• Variation in water quality, pathogen loading
• Rise in ocean levels causing salt water
  intrusion, habitat destruction, and displacement
  of significant human and animal populations

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Inventory of AWs 2007 Green House Gas Emissions
1. Emissions in metric tons CO2e includes CO2,
N2O and methane emissions 2. Emissions from
flared methane gas and HVAC were both lt0.5
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How Much Electricity Does the Water Industry Use?

• Drinking water and wastewater consume
• 3 of domestic electricity1
• 7 of worldwide electricity
• 19 of California electricity2
• Water utility energy use varies widely from 0.25
  to 3.5 kWh per 1,000 gallons of drinking water
  produced and delivered3
• The median 50 of water utilities serving
  populations gt10,000 had electricity use between
  1.0 and 2.5 kWh/1,000 gallons3

• Electric Power Research Institute (Burton 1996)
• Energy Down the Drain The Hidden Costs of
  Californias Water Supply
• AwwaRF 91201.Energy Index Development for
  Benchmarking Water and Wastewater Utilities

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Emerging Technologies Use More Energy

• New regulations are increasing the use of the
  following, energy intensive treatment processes
• Added Technology Additional Energy
• UV Disinfection 70-100 kilowatt
  hours/million gallons
• Ozone 170 kilowatt
  hours/million gallons
• Membranes
• Nano and RO 1,800 kilowatt hours/million
  gallons
• Ultrafiltration 1,000 kilowatt hours/million
  gallons Microfiltration 100
  kilowatt hours/million gallons

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Pumping Accounts for the Biggest Energy Use

• 85-99 of water treatment plant electric
  consumption goes to pumping.
• Raw water well pumps
• High service pumps
• Filter backwash pumps
• Distribution system booster pumps

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2. Infrastructure Integrity

• American Society of Civil Engineers
• Each day, approximately six billion gallons of
  treated drinking water are lost primarily due
  to system leaks throughout the United States.
• This is approximately 14 of the nations total
  daily water production.
• American Water is responsible for 44,000 miles of
  main.

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MLOG Acoustic Monitor

• Installed near a water meter. Easily strapped to
  service pipe or meter.
• Maintenance-free, can survive meter pit
  environment.
• Battery Life Radio MLOG 8 years and Fixed
  Network 15 years.
• Fixed Network AMR sends data to host, to Website
  daily. Mobile Units, a separate controller unit
  acquires up to 11 days of history.
• Proposed Future Unit Low Cost Unit at Every Meter

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• A pilot study of 500 MLOG units in Connellsville,
  PA has reduced 50 of the annual non-revenue
  water loss within the first few weeks of
  monitoring. Estimated pay-back in 6-8 months.
• Finding leaks in the City of Connellsville, PA
  like this pinhole leak in a cast iron pipe under
  a concrete sewer pipe.

• Research will evaluate whether most winter breaks
  are actually unseen leaks that can be repaired
  before the disruptive main break event ever
  begins

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Infrastructure Assessment

• 19 of the 40 leaks were identified by acoustic
  monitors and repaired in advance of surfacing.
  Another 6 were MLOG identified before surfacing
  but appeared before repair made. The remaining
  15 surfaced and were repaired.

We can anticipate leak occurring after a water
temperature drop in surface supply systems.
Definite higher noise in extremes of heat and
cold. There are patterns that repeat
annually. Optimum time for leak detection appears
to be the fall.
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3. Distribution System Integrity

• The hydraulic integrity of a water distribution
  system is defined as its ability to provide a
  reliable water supply at an acceptable level of
  servicemeeting all demands for adequate
  pressure, fire protection, and reliability of
  uninterrupted supply.
• The most critical component of hydraulic
  integrity is adequate pressure defined in terms
  of the minimum and maximum design pressure.
• A second element of hydraulic integrity is the
  reliability of supply, which refers to the
  ability of the system to maintain the desirable
  flow rate even when components are out of
  service.

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Example Pressures Transient
Negative for gt 16 sec as low as 10.1 psi (-69
kPa)
Gullick et al. 2005. J. Water Supply Technol.
AQUA 54(2) 65-81.
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Separation from Sewer Lines

• Typical separation distance 10 feet (3 m)
• Standards allow for minimum of 18 in. (0.5 m)
  separation

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Backflow Sensing Meters West Virginia

• 0.1 gallons
• 10 gallons

• Low level event gt0.10 gallons of backflow in any
  15 minute interval
• High level event gt10.0 gallons in any 15 minute
  internal
• In one 35 day data set there were 199 events
  (5.1) in 3900 customers
• 163 locations with low level backflow (4.2)
• 36 locations with high level backflow (0.9)

Main Break
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Field Test Results Pennsylvania

• Installed gt3,300 meters
• Found 51 instances of backflow in 1 month
• 13 instances of gt10 gal
• 38 instances of 1-10 gal
• Pattern indicative of main break or pump shutdown
• Several isolated spots warrant further
  investigation
• Possible tampering
• Private wells

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Backflow Occurrence Rates

• New Jersey
• Unique Premises
• Month Meters Positive Positive
  Positive Positive
• September 142 4
  2.8 4 2.8
• November 143 3
  2.1 3 2.1
• December 147 2
  1.4 0 0
• February 151 2
  1.3 0 0
• March 149 2 1.3
  0 0
• April 150 2
  1.3 0 0
• May 151 1 0.7
  0 0
• June 148 2 1.3
  1 0.7
• July 195 4 2.1
  2 1.0
• Total 1,376 22 1.6
  10 5.0

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Backflow Occurrence Rates
Pennsylvania
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Backflow Occurrence Rates
West Virginia
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Automating Backflow Alarms

• Advanced Metering Infrastructure (AMI) and
  metering systems can work together to send
  backflow alarm immediately after indicator is
  detected.
• As part of our AwwaRF AMI research project,
  backflow reports are generated from daily reads
• Over a 3-month period some locations experienced
  backflow 39 to 41 times

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4. Security

• Since 9/11 there has been heightened interest in
  how water systems could be compromised through
  terrorist attack or accident.
• Collaborative project with the USEPA and the
  USGS to evaluate multi-parameter on-line
  sensors.
• YSI (Yellow Spring Instruments) provided the
  6920DW probe that measures temperature, pH,
  specific conductance, ORP (oxidation-reduction
  potential), turbidity, and free chlorine.
• 18 units were deployed in the NJ American, Delran
  distribution system and linked by telemetry to
  the SCADA system. Between 110,000 and 220,000
  data points collected.

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Sensor Location
Practical Locations
Optimal Locations

• USEPA TEVA model used Monte Carlo simulations
  for various scenarios
• Contaminant concentration
• Injection site
• Duration (or rate) of injection
• Exposure

All non-zero demand nodes assumed to be equally
vulnerable to introduction of the biological or
chemical contaminants. Time delay from
detection to implementation of a mitigation
response assumed to be zero.
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Public Health Benefits with Various Sensor
Designs
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5. Water Quality Risk Modeling

• Quantitative Microbial Risk Assessments (QMRA) is
  a powerful tool for organizing and assessing
  microbial data.
• American Academy of Microbiology Report
• The greatest value in microbial risk assessment
  is in the development of the model not
  necessarily in the final answer.
• Proper application of microbial risk assessments
  can be valuable in guiding selection and
  application of treatment processes
• The microbial risk assessment process is
  iterative there is not single start or ending
  point.

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QMRA for negative Pressure Transients
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Coincidence of Transient and Consumption

• Intrusion
• Duration 16s
• avg flow before transient period 36 gpm

People consuming water over 1 hour period, would
have a 0.4 (16/3600) probability of drinking
contaminated water
Therefore, the duration of the transient is
important!
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6. Wastewater Infrastructure

• The physical condition of the nation's 16,000
  wastewater treatment systems is poor, due to a
  lack of investment in plant, equipment and other
  capital improvements.
• Aging wastewater management systems discharge 850
  billion gallons of untreated sewage into U.S.
  surface waters each year.
• Sanitary sewer overflows (SSOs), caused by
  blocked or broken pipes, result in the release
  of as much as 10 billion gallons of raw sewage
  yearly
• The EPA estimates that the nation must invest
  390 billion over the next 20 years to replace
  existing systems and build new ones to meet
  increasing demands.

American Society of Civil Engineers
www.asce.org/reportcard
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Electroscanning

• Simplified Electrical System

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Electroscanning Pipe Trace
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Electroscanning is more Effective than
Conventional CCTV
Compared to CCTV, Electroscanning was More
effective 1.7 to 21 times Lower cost 50 to
80 less Greater productivity 30 to 50 greater
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Wastewater Infrastructure Cost Model
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7. Reuse of Treated Wastewater

• Water reuse in the U.S. is a large and growing
  practice
• Nationally, an estimated 1.7 billion gallons per
  day is reused.
• Reclaimed water use on a volume basis is growing
  an estimated 15 per year.
• In 2002, Florida reclaimed 584 mgd. California
  ranked a close second with 525 mgd used daily.
• Florida has an official goal of reclaiming 1
  billion gallon per day by the year 2010.
• Other leaders Texas, Arizona, Nevada, Colorado,
  Georgia, Washington

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Sites 23 and 24
Millennium Towers
Solaire
Tribeca Green
Visionaire
River House
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Sewer Mining Immediate Benefits

• Enhances collection system capacity
• Increases drinking water supply reliability
• Minimizes infrastructure requirements
• Reclaimed water distribution requirements kept at
  a minimum
• Saves on pumping costs of reuse water
• Enhanced Sustainability
• Waste Activated Sludge to collection system
• Improves odor control
• In-pipe treatment
• Provides planning, operating and capital
  investment flexibility
• Tailored Treatment

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8. Desalination

• Worldwide, the desalination market soared from
  2.5 bn in 2002 to 3.8 bn in 2005 with a growth
  rate over 15 per annum.
• Over 50 of the US population live in coastal
  areas.
• Frost Sullivan reports that the "U.S.
  Desalination Pretreatment Market" will double
  from 184.0 million in 2005 to 399.6 million in
  2012
• Key issues
• Brine Disposal
• Pretreatment (biofouling)
• Energy Conservation
• Productivity
• Operational Experience

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And California too
Moss Landing, Monterey
Carlsbad Desalination Plant
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Control of Membrane Fouling

• In drinking water the presence of assimilable
  organic carbon is known to be associated with
  growth of biofilms
• Development of a bioluminescence AOC test has
  permitted rapid, low cost, measurements
• Application for reclaimed waters
• Development of a salt-water test can evaluate the
  effectiveness of desalination pre-treatment
  processes

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9. Energy Water Nexus

• The U.S. Energy Policy Act of 2005
  established the DOEs role in energy and water
  related issues.
• The DOEs Sandia National Lab states that
• Energy and Water are inextricably linked
• That link is vital to U.S. security and economic
  health
• The nations ability to continue providing both
  clean, affordable energy and water is being
  seriously challenged by a number of emerging
  issues

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Water Use for Mining of Oil, Gas, and Coal
Mon River quality up after limits on drillers By
The Tribune-Review Thursday, January 22, 2009
State concerned about waste water from new gas
wells Sunday, December 21, 2008 By Don Hopey,
Pittsburgh Post-Gazette
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Canal Road Solar Array, NJ
590 kW ground-mounted photovoltaic
system Produces 687,000 kilowatts of energy /
year Eliminates 493,835 pounds (224 metric
tons) of CO2e per year
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Bioenergy Recovery

• Widely used with natural gas
• Increased number of applications for Digester Gas
• Typical Applications for Digester Gas
• Power to the Electric Grid (Green Power- RECs)
• Heat to heat digestion process
• And Building HVAC
• Documented case studies for Fuel Cells,
  Microturbines, Combustion Engines

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Co-Location with Landfill Biogas

• Landfill located two (2) miles from water pumping
  station
• The landfill currently is flaring its methane
• The pump station uses close to 500 kW of electric
  power
• The pump station has an emergency power generator
  to run on natural gas
• Easy conversion of generator to biogas
• Landfill has 10x more gas than needed to run the
  generator

Raw Water Pump Station
Landfill
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10. Alternative Delivery Systems

• In 100 years will anyone drink piped water?
• In a hydrogen economy water will be a by-product
  of energy production
• Drinking water is already produced on the space
  station
• Water companies will be stewards of the water
  cycle and protectors of the environment
• Transition from public health protection to
  environmental protection
• Communicate the value of water

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Conclusion

• This is an exciting time to work in the water
  industry
• Challenges provide opportunities for innovative
  solutions
• The aging water industry workforce will require
  new professionals
• 10-15 of engineering and other technical and
  scientific professionals will retire in the next
  5 years
• Students should consider an exciting,
  challenging, and immensely rewarding career in
  the water industry
• The work that you will do will save lives,
  protect public health, and protect the
  environment at same time as providing a vital
  and necessary service.
• Maybe thats the final challenge!

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Thank you for your attention!
Acknowledgements
Support was provided by the utility subsidiaries
of American Water
Contact Information
Mark W. LeChevallier, Ph.D. Director, Innovation
Environmental Stewardship American Water 1025
Laurel Oak Road Voorhees, NJ 08043 USA phone
[phone] fax [phone] e-mail
mark.lechevallier_at_amwater.com