water and sewage systems for future cities. cases: new york and bangalore
DESCRIPTION
Infrastructure 2013: Water Presentation from the first 'Infrastructure 2013' evening seminar on access to clean water and water managment in growing cities. Seminar held in Oslo 20 March 2013. Vann og avløpsløsninger i fremtidens byer. Case Bangalore/New York Petter D Jenssen, Universitetet for Miljø og Biovitenskap (UMB)Association for International Water Studies)TRANSCRIPT
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Phewa lake, Pokhara
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Vann- og avløpsløsninger for framtidens byer med eksempler bl.a. fra New York og Bangalore
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Petter D. Jenssen Department of Plant and Environmental Sciences, Norwegian University of Life Sciences
Habitat Norway - Infrastructure 2013 20. mars,2013
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1,2 billion people do not have access to clean water
3,4 million people die anually due to diseses caused by lack of proper water and sanitation
2,5 billion people lack proper sanitation
UN summit Johannesburg 2000 - goals:• Halve the number of people without access to clean water within the year 2015• Halve the number of people lacking proper sanitation within the year 2015
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Department of Plant and Environmental Sciences
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DO less than 1 mg/l
BOD - 250 mg
Kathmandu, Nepal
Dry season:
(Pandey et al. 2005)
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90% of the wastewater in the world is discharged untreated
Current situation:
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P.D. Jenssen IPM/UMB
Repair of infrastructure (Norway) 500 billion NOK
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Data from: Cordell et al. 2009
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Photo: P. Jenssen
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Photo: P. Jenssen
20-40% of the water consumption in sewered cities is used for flushing toilets
(Gardner 1996)
P.D. Jenssen IPM/UMB
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Future solutions for megacities ?
Photo: P. Jenssen
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(Alsen and Jenssen2005)
Source separation of wastewater
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Nitrogen Phosphorous Potassium Volume
GreywaterFaecesUrine
Nutrients and volume of domestic wastewater fractions
(Jönsson et al., 2000).
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Nitrogen Phosphorous Potassium Volume
GreywaterFaecesUrine
Nutrients and volume of domestic wastewater fractions
(Jönsson et al., 2000).
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Nitrogen Phosphorous Potassium Volume
GreywaterFaecesUrine
Nutrients and volume of domestic wastewater fractions
(Jönsson et al., 2000).
1 % of the volumecontains: >80% of the resources
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(Alsen and Jenssen2005)
Source separation of wastewater
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Future toilet types(commercially available today)
• Composting /dry sanitation 0 - 0.1 liter/visit• Low flush (urine diverting) 0.1 - 4.0 liter/visit
• Low flush (vacuum&gravity) 0.5 - 1.0 liter/visit
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Composting toilet at roadside facility - Sweden
Clean odourlesstoilets
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Composting toilet at roadside facility - Sweden
Elected the best roadside facilityin Sweden 2003
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• Urine flushed with 1-2 dl
• Faeces - flushed with 2-4 liters
Dual flush urine -diverting system
(Jønsson et al. 1998)
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Waterless urinals
Kastrup airportCopenhagen
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Lavtspylende toaletterVacuum
0.5 - 1.5 liters/flush
Gravity 1 liter/flush
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Future solution using source separation:
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Future solution using source separation:
Is it technically possible in urban areas?
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Future solution using source separation:
Is it technically possible in urban areas?
What is the cost?
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Decentralized greywater treatment in urban areas - Klosterenga, OSLO
Klosterenga
Compiled by: Petter D. Jenssen, Norwegian University of Life Sciences (UMB)
Klosterenga oversikt
PretreatmentBiofilter (PBF)
Horisontalsubsurfaceflow CW• 33 apartments
• 100 persons• Area 1m2/person
Greywater treatment in urban areas - Klosterenga, OSLO
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Greywater treatment at Klosterenga Oslo
Effluent values:Fecal coliforms: <10Total-N: 2,5 mg/lTotal-P: 0,02 mg/l
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Local discharge
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Irrigation
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Groundwater recharge
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Departm
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?
Greywater treatment at Klosterenga Oslo
Effluent values:Fecal coliforms: <10Total-N: 2,5 mg/lTotal-P: 0,02 mg/l
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Rainwater catchment
Greywater Treatment
Plant
Urinediverting
toilet
Dug well for Ground water
recharge
Water collection Tank
House Without City Water Supply Reuse & Recycle of
Waste
Built in 2002 occupies 135 m2 Area
(R. Shrestha 2006)
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Faeces after 5 to 6
months
(R. Shrestha 2006)
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(R. Shrestha 2006)
Composted faeces and urine as fertilizer
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(R. Shrestha 2006)
Treated greywater for irrigation and groundwater recharge
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(R. Shrestha 2006)
Watering and car washingeven in dry periods
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(R. Shrestha 2006)
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House Without City Water Supply Reuse & Recycle of
Waste
Built in 2002 occupies 135 m2 Area
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Bangalore India
Well
Sewer
Photos: J. Heeb
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Ecosan toiletcenter
Photos: J. Heeb
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Ecosan toilet center Bangalore India
Faeces
Urine
Wash water
Photos: J. Heeb
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Serves 800 people Produces 50 tonn
bananas/year Produces compost for
sale Employs 10 people Annual cost 10
US$/userPhoto: J. Heeb
Ecosan toilet center Bangalore India
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Waste as a resource
Photos J. Heeb
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Solutions for megacities ?
Photo: P. Jenssen
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Department of Plant and Environmental Sciences
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Photo: P. Jenssen
20-40% of the water consumption in sewered cities is used for flushing toiles
(Gardner 1996)
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• 1660 vacuum toilets• > 2km of vacuum sewer line
(Jets TM)
Vacuum technology Marine installations
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(Jets TM)
Vacuum technology
Marine installations
BiofilterRotating biological contactors
Norwegian University of Life Sciences (UMB)
Kildesep prinsippPlant for production of bioenergy and solidified fertilizerChallenges ?
• Logistics of blackwater transport•Treatment of blackwater
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Cost aspects
Jenssen og Vatn inn her
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From: Jenssen and Vatn 1991
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Kuching Sarawak Malaysia
Population: 500 000
P.D. Jenssen IPM/UMB
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Norwegian technology
Source separating system - Kuching, Malaysia
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Costs (MYR) conventional vs. decentralized
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Investment cost of centralized sewer systems
Wastewater treatment plant
Sewer lines
Collection system 70 - 90%
Treatment 10 - 30%
(Otis 1996, Mork et al. 2000)
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The blackwater system KuchingConverting the septic tank to a holding tank
Holding tank
Metering gage
3. Fitting a quick coupling for easy pump out
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Pump out time reducedto 6 minutes/tank
The blackwater system - Kuching
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Proposed biogas plant
P.D. Jenssen IPM/UMB
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(Alsen and Jenssen2005)
Source separation of wastewater
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(Alsen and Jenssen2005)
Source separation of wastewater
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Pilot project Hui Sing GardenGreywater treatmentPhoto: P. D. Jenssen
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Greywater treatment - Hui Sing Garden
Preliminary results:
BOD < 2 mg/l
Total N 2.2 mg/l
Total P 1.9
Faecal coliforms 50/100ml
Photos: P. D. Jenssen
(Jenssen et al. 2005)
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Blackwater
Greywater
Source separation of domestic wastewater - Pinggu
P. D. Jenssen IPM/UMB
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Blackwater to biogas and fertilizer
Greywater
Source separation of domestic wastewater - Pinggu
P. D. Jenssen IPM/UMB
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Blackwater to biogas and fertilizer
Greywater to:
Drinking water
Irrigation
Groundwater recharge
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Blackwater to biogas and fertilizer
Greywater to:
Drinking water ?
Irrigation
Groundwater recharge
Greywater recycling
90% watersaving is possible !
P. D. Jenssen IPM/UMB
Conclusion:Large scale urban application of ecological
sanitation is no longer a far fetched scenario
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Greywater treatment at Klosterenga Oslo
Effluent values:Fecal coliforms: <10Total-N: 2,5 mg/lTotal-P: 0,02 mg/l
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Conclusions - source separating systems
Norwegian University of Life Sciences (UMB)
Can be implemented sector by sector, thus distributing investment cost in time
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Systems using separate treatment of excreta and greywater provide many new solutions to sanitary challenges in rural and peri-urban areas, but these source separating systems can also be used to sewer urban areas in a sustainable way.
Source separating systems facilitates production of bioenergy (biogas) as part of blackwater treatment. The gas production is greatly improved by co-treatment of blackwater and other waste resources as organic household waste.6
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Conclusions - source separation
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Conclusions - source separation
Water saving up to 40% due to use of water efficient toilets. If greywater is treated and recycled >90% water saving is possible, thus reducing the water footprint by a factor 10. Greywater can be treated to bathing water in compact in-house systems or in simple biological systems integrated in green areas. This opens for local discharge, groundwater recycling, use in irrigation or uprading to potable water quality through e.g. membrane filtration.
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Conclusions - source separationIt is assumed that an immediate transfer to source separating systems in urban areas will initially be more costly than continuing the present systems, but with time environmental benefits will make source separating systems more cost efficient (Jenssen and Vatn 2001) In the environmental building at Klosterenga in Oslo a dual plumbing system with vacuum toilets was calculated to the same investment cost as traditional plumbing.In Kuching (a city of 500000 people) in Malaysia with a non existent sewer collection system a source separating system with processing of blackwater to biogas and fertilizer and local greywater treatment was calculated to be 25% cheaper than centralized collection and biological treatment.
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ConclusionFor urban areas without a centralized collection
system, especially:Consider to go straight to water-saving and recycling, often
decentralized and source separating sanitary systems
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