Water Challenges - Past, Present, and Future Perry L. McCarty Department of Civil and Environmental Engineering Stanford University
Water Supply and Distribution Listed by the National Academy of Engineering as among the Greatest Engineering Achievements of the 20th Century
50 Years Ago - The arrival of new problems - bring a paradigm shift
Cuyahoga River, Cleveland, Ohio - 1952 - Burn on, Big River, Burn on Photographer - James Thomas
San Francisco - 1971 Oil Spill National Geographic magazine photographs
Aerobic - Activated Sludge Treatment Toronto San Jose Chicago Los Angeles County
ABS Synthetic Detergents 1950s Photographer - Bruce M. Wyckoff
Whittier Narrows, CA 1962 Wastewater Reuse
1962
1965 - South Lake Tahoe Advanced Wastewater Treatment
1968 - Direct Potable Reuse, Windhoek, Namibia
Orange County, California 1976 - Water Factory 21
Super Fund - 1980
Global Annual Production of Synthetic Organic Material (Source UNEP, 1987) Million Tons per Year 300 200 100 0 1920 1940 1960 1980 2000
Emerging Chemicals of Concern Perchlorate (ClO 4- ) Nitrosodimethylamine (NDMA) 1,4-Dioxane Fire retardants PBDE Perfluoros Pharmaceuticals Endocrine disrupters Fish Feminization
Worldwide Problem Over 1 billion people lack access to safe drinking water 2.4 billion lack access to adequate sanitation facilities In 1998, 2.2 million people estimated to have died of diarrheal diseases Millions suffer from parasitic worm infections
An Inconvenient Truth San Jose Mercury News April 3, 2007 New York Times April 3, 2007 Wall Street Journal April 3, 2007 Supreme Court ruled that carbon dioxide and other so-called greenhouse gases are air pollutants Wall Street Journal, April 3, 2007
Question What is impact of wastes and waste treatment on greenhouse gas emissions?
Global Warming Potential CO 2 = 1 Gas Carbon Dioxide (CO 2 ) Methane (CH 4 ) Nitrous Oxide (N 2 O) GWP 1 21 310
Global Anthropogenic Greenhouse Gas Emissions N 2 O 8% Other 1% CH 4 15% CO 2 76% US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA 430-06-005
Anaerobic Pathways to Methane Formation Anaerobic Digestion, Elsevier (1981)
Anaerobic Treatment
Anaerobic Treatment in China
2000 Non-CO 2 Emissions - % of Total CO 2 eq 25 Percent 20 15 10 5 0 Wastes Other Agriculture Enteric Ferment Rice Fossil Fuels World USA US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA 430-06-005
2000 Waste CH 4 +N 2 O Emissions - % of Total CO 2 eq 5 Percent 4 3 2 CH 4 N 2 O 1.3 1.0 Waste- Water Manure 0.6 0.9 1 1.8 Solid Wastes 2.1 0 World USA US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA 430-06-005
TUESDAY, NOVEMBER 6, 2007 SAN JOSE MERCURY NEWS SAN JOSE MERCURY NEWS TUESDAY, NOVEMBER 6, 2007
Water-Related Energy Consumption in California (2001) 35 % of CA Energy Usage 30 25 20 15 10 5 0 1 2 Electricity Heating & Cooling End Use T & T Natural Gas California Energy Commission, CEC-700-2005-001-SF (2005)
kwh/million Gallons for Urban Water in California Supply & Convey Water Treatment Water Distribution Wastewater Treat. Total North 150 100 1,200 2,500 3,950 South 8,900 100 1,200 2,500 12,700 California Energy Commission, CEC-700-2005-001-SF (2005)
Rene Dubois Think globally, act locally
2005 - U. S. Anthropogenic Greenhouse Gas Emissions Passenger Car 8.7% Source: US EPA, Inventory of U. S. Greenhouse Gas Emissions and Sinks: 1990-2005, Draft, February 20, 2007
Question How can we reduce energy consumption and greenhouse emissions from wastewater treatment?
2007 Google-Map Data NAVTEQTM
Palo Alto Wastewater Treatment Plant Primary settling Aerobic BOD removal Nitrification Sludge incineration
San Jose Wastewater Treatment Plant Primary settling Aerobic BOD removal Nitrification Sludge digestion
Sunnyvale WTP Stabilization Ponds
2007Google-Map Data NAVTEQTM
Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Flotation Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Nitrification Flotation Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Nitrification Flotation Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Nitrification Flotation Disinfection Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Stabilization Ponds Nitrification Flotation Disinfection Effluent Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent
Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM
Flotation Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM
CO 2 + CH 4 Flotation Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM
CO 2 + CH 4 Flotation Digesters Primary Tanks Drying Beds 2007Google-Map Data NAVTEQ TM
BOD Conversion to Algae Particulate C 5 H 7 O 2 N BOD 5O 2 5CO 2 + 2H 2 O+ Soluble NH 3 C 5 H 7 O 2 N
Cogeneration at Sunnyvale Wastewater Treatment Plant
CO 2 & N 2 O Release in Nitrification CO 2 Plus trace of N 2 O NH 3 + 20 2 + NaHCO 3 = Power Air NaNO 3 + 2H 2 O + CO 2
CO 2 Equivalents (1000 kg/day) Treatment of 10,000 kg BOD 5 /day BOD Removal CH 4 Oxidation CH 4 Loss (1%) Nitrification Energy Usage Total Aerobic + Incineration 3.6 Incineration 20.4 Digestion-CO 2 2.8 2.2 29.0 Aerobic + Digestion 3.6 2.6 5.4 1.1 2.8 (3.3) 12.2 Algae + Digestion 3.4 6.8 1.4 1.2 (6.6) 6.2
Energy Costs - US$1000/year Treatment of 10,000 kg BOD 5 /day Aerobic + Incineration Aerobic + Digestion Algae + Digestion Oxygen Supply 178 178 CO 2 Penalty 58 24 12 Excess Power (299) (378) Total 236 (97) (366) CO 2 penalty = US$20/tonC
Water Reuse in Monterey County
Monterey Regional Water Pollution Control Agency Largest wastewater recycle in U.S. for irrigated crops Irrigates 12,000 acres 34.2 billion gallons produced since 1997
Water Reuse in Monterey County
Conclusions for Sustainability A reevaluation of waste treatment alternatives is needed because of climate change concerns Methane from wastes must be contained Desired alternatives are those that reduce both greenhouse gas emissions and power consumption Anaerobic treatment is likely to be an attractive component of the alternatives Wastewater is a resource for water, energy, and plant nutrients
Rene Dubois "Trend is not destiny"
Ancient Chinese Proverb "Unless we change our direction, we are likely to end up where we are headed"
Thank you!