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Rainwater Harvesting in the rural context:
Can SODIS treated meteoric water reduce the impact of geogenic contamination on human health?
Ankit Labh( MS13003 ) 23rd Feb 2016
Outline
• Rainwater Harvestingo Study of Darbhanga,Bihar
• (Solar Disinfection ) SODISo Case Study of Tamil Naduo Study at NSU, South Koreao Case Study of Sikkimo Study of Betwa river, Bhopalo Reports from Lumbini, Nepal.
• Conclusion
• International Recognition
Rainwater Harvesting:
RAINWATER HARVESTING is a process involving collection and storage of rain water (with the help of artificially designed system) that runs off natural or man-made catchment areas.
Activity of direct collection of rainwater
Water Crisis – Why?
• Over exploitation of current sources
• Low natural recharge due to urbanization
• Fear of Failure of monsoon
Average mean annual rainfall in India:
License: Creative Commons Attribution-Share Alike 3.0 ;Wikipedia
Average annual evaporation in India:
http://cwc.gov.in/main/downloads/Evaporation%20Control%20in%20reservoirs.pdf
Aquifer system in India:
Central Ground water BoardLand Use and Water Resources Research 6 (2006) 1-17
What are the solution?
• Rainwater is ultimate source of fresh water
• Potential of rainwater to meet water demand
• To conserve ground water, aquifers must be recharged with rainwater
• Rainwater harvesting is the ultimate answer
Methods for Rainwater harvesting:
Roof RWH system at Patkhori High School in Mewat, Haryana
Methods of Rainwater Harvesting:
1) Roof –top Harvesting Open well method Bore well method
2)Foot-top / Open space harvesting Percolation or Recharge pit Recharge Well
Study of RWH at Darbhanga, Bihar
• North District of Bihar.
• 5th largest city of Bihar
• According to 2011 census, 91.30% live in rural areas.
• May is the hottest month when the temperature goes up to 47°C.
• Average annual rainfall of this district is 1142.3 mm /year.
Darbhanga: Temperature History
Source: MSN weather
Darbhanga: Precipitation History
Source: MSN weather
Role of Catchment area in RWH:
Catchment area or roof will determine how much rainwater you can harvest.
Differences in roof slope do not change this building’s catchment area
http://rainwaterharvesting.tamu.edu/catchment-area/vv
The catchment area is the first point of contact for rainfall.
1 L = 0.26417 Gallon1 m2 = 10.7639 feet1 m = 39.3701 inch
How much water can be harvested?(Indira Awas Yojna )• Average annual rainfall of Darbhanga District is 1149.9 mm /year.
• Volume of water collected @terrace 20 m2 X 0.5 m = 10 m3 = 10,000 L
(As per IAY) (only 43% of annual rainfall)
• 10,000 Liter per year could be harvested from one house even when we assumes that not 100 % but only 43 % could be harvested.
• Basic minimum need per day is 40 L/day. So this much water is enough for 250 days an year for a single person. (70% time an year)
[IAY = Indiara Awas Yojna]
Under the “Accelerated Rural Water Supply Programme (ARWSP)” guideline the norms for providing potable drinking water to the rural population based on basic minimum need per day is as follows:
Rajiv Gandhi National Drinking Water Mission ;National Rural Drinking Water Programme (2010 report)
lpcd(litres per capita daily)
Safe Water definition as per IS-10500 Standard of BIS
Rajiv Gandhi National Drinking Water Mission ;National Rural Drinking Water Programme (2010 report)
SODISSolar Disinfection
Introduction of SODIS(Solar Disinfection )
• simple low-cost, household-level drinking water treatment technology
• uses solar radiation to improves microbiological quality of drinking water
• one of the recommended HWTS by World Health Organisation (WHO).
SODIS applicability on Globe
http://www.matthewb.id.au/media/world_insolation_map.gif
Science behind SODIS :• SODIS process consists mainly of UV-A light (320
to 400 nm), which makes 6% of the total solar light. UV-A radiation directly interacts with the DNA, nucleic acids and enzymes of the living cells, changes the molecular structure and leads to cell death.
• Oxygen was later identified as a crucial component of the solar disinfection process.
• UV-A radiation generates oxygen radicals that are essential for the inactivation of microorganisms (Reed, 1997, Reed et al., 2000).
• To achieve an equilibrium between oxygen levels in air and water, potential users are recommended to shake bottles before sun exposure (Kehoe et al., 2001)
Efficiency:
• For efficient SODIS, a geographical area should receive radiation above 500 W/m2 for 3–5 hours.
[J Water Supply Res T 43(3): 154–169]
• The inactivation rate under sunny weather condition with different rear surface was in order as absorptive>reflective>transparent containers
Case Study of Tamil Nadu, Indiao In Tamil Nadu, about 72% of the population has
no access to clean drinking water
o Gastrointestinal diseases and Cholera epidemics are therefore widespread
o Study of five districts along the Cauvery Basin: Trichi, Erode, Perambalur, Karur and Pudukkottai
o Groundwater is the main source of drinking water and private pumps, pond water are also common.
o Bottle Supply system has been established with the help of local NGO and local volunteers
Study in Field:o Over 2 years, 41450 families have been trained in improved hygiene practices and the application of SODIS.
o 90% of all the samples tested contained bacteria counts of 100 to 1000 colonies per 100ml.
Results:o The strong contamination of the raw water, the tests
showed that SODIS treated water contained 0(zero) colonies of bacteria in 71.4% of the samples.
http://www.sswm.info/sites/default/files/reference_attachments/LEAD%20n.y.%20Sodis%20Case%20study%20Tamil%20Nadu%20India.pdf
Presenting the results of the water quality tests to the community at TN(left: Raw water, right: SODIS water)
http://www.sswm.info/sites/default/files/reference_attachments/LEAD%20n.y.%20Sodis%20Case%20study%20Tamil%20Nadu%20India.pdf
Result of Study
The survey on the acceptance of SODIS revealed that from the people trained there are 47.6% regular users, 45.2% irregular users and 7.1% non users
Regular : 26 days per month, 2 bottle per person.
More than 50% household members consume SODIS water
Study at Energy Centre, MANIT, Bhopal, M.P.[Lower lake and Betwa river]
WATER PURIFICATION USING IMPROVED SODIS,LPU
Temperature measurement
Sample 1 (Normal TAP Water)Sample 2 (TAP Water with Activated Carbon) 10 mg/ LtSample 3 (TAP Water with TiO2 Nano powder) 10 mg/ Lt.
Irradiance change under different weather conditions[ study at NSU, South Korea]
Temperature change in PET bottles with different rear surfaces against exposure time under (a) sunny, (b) mild, and (c) weak weather conditions
Amin MT, Nawaz M, Amin MN, Han M (2014) Solar Disinfection of Pseudomonas aeruginosa in Harvested Rainwater: A Step towards Potability of Rainwater. PLoS ONE 9(3): e90743. doi:10.1371/journal.pone.0090743
Treatment Efficiency:
Microbiological studies demonstrate effectiveness of SODIS against a range of germs
Case Study of SODIS in Sikkim
• South District (Namchi) was selected for study
• Source of Water : Rangit River and spring water
• 102 households identified having >1 under-five children (136 Children)
Result of Diarrhea prevention in Sikkim, INDIA
No. of households
No. of children No. of diarrheal cases
SODIS users 52 66 05 (7.58 %)
SODIS non-users
50 70 22 (31.43%)
Prevalence of diarrhea among underfive children who used SODIS and those who did not (after eight weeks of intervention)
J Glob Infect Dis. 2010 Sep-Dec; 2(3): 221–225.
Results of SODIS in Lumbini, Nepal
http://www.grilink.org/ibsrepor.htm
All Villages:- Sujandihawa, Bhagawanpur, Mujhana,Lamthihawa,Mahuwari, Sonbarsha, Ramwapur,Dhodahawa,Shivgadhiya
In Indian Context
• A daunting number of 96 million people in India lack access to safe drinking water
• UN supports SODIS programme at 3 regions in India :-
1. Tamil Nadu2. Northeast (Asom,West Bengal)3. Delhi
• More than 270 000 households are already using SODIS in india
Pathogenic enteric bacteria are a major cause of drinking water related morbidity and mortality in the developing world .
(WHO,2008).
More than four percent of the global DALYs (Disability Adjusted Life Years) were ascribed to diarrheal diseases, which ranked fourth among the most important contributors to the global illness burden, after lower respiratory infections (6.1% of total), HIV/AIDS (5.7%) and unipolar depressive disorders (4.5%).
[World Health Report’s estimates (2004)]
Effect in general
Global Scene :
According to the latest available information by the joint study of UNICEF and WHO, still 783 million people do not have access to safe water resources.
Over 1.2 million children, most being less than five years old, die due to diarrheal diseases each year
What are the mistakes often made by new sodis users?• Green or brown plastic bottles are used for SODIS. => such bottles do not
transmit the UV-A light. Therefore use clear transparent bottles only.
• The containers chosen are too big. => optimally plastic bottles of 1-2 liters volumes are used (better surface/volume ratio).
• Bottles are placed upright. => Instead of this: laying the bottles horizontally increases the area for sunlight exposure and reduces water depth. (At a water depth of 10cm and moderate turbidity level of 26 NTU, UV-A radiation is reduced to 50%)
• After SODIS treatment, the clean water is filled into contaminated containers and the water is recontaminated. => Instead of this: consume the treated water directly from the bottle using a clean glass or a cup.
Problems with practical use
• Turbidity Problem : SODIS to be very effective turbidity should be less than 30 NTU (= Nephelometric Turbidity units)
• Cloudy Time: It is hard to give full SODIS treatment in time limit of 6 hr if it is full of clouds. So, One needs at least 2 continuous days for full treatment.
Advantages:
• Improves microbiological quality of drinking water
• Extremely low-cost
• Easy to understand and simple to use
• Relies on locally available resources, plastic bottles and sunlight
Disadvantages: Not alternative of fresh water • Does not treat chemical pollution
• Is strongly climate and weather dependent
• Only small volumes can be treated at a time and regardless the simplicity
• Requires the availability of PET bottles (or plastic bags) and needs promotion
Conclusion:
• Rain Water Harvesting is the best technique one can apply to serve the earth and himself
• under normal conditions SODIS shows an efficiency of about 99.9%
• SODIS works well and can be adopted wherever it needs. It secures the ‘Basics Right to Live’ to some extent.
International recognition:
• The World Health Organization (WHO), UNICEF, and the Red Cross therefore recommend the SODIS method as a way to treat drinking water in developing countries.
• “Solar disinfection is an example of another measure with proven health impact that requires little capital investment on the part of end-users, and is thus appropriate for the very poor.” WHO, 2007
• “UNICEF promotes a variety of treatment methods such as user-friendly filtration, simple solar water disinfection (SODIS) and home chlorination. These are all low-cost, effective and manageable at the household level.” UNICEF, 2009
• Red Cross Prize, 2006: "The jury considers SODIS an impressive way of contributing by the simplest means to making water supplies better and safer, thereby reducing diarrhea and other diseases like it, and mortality in developing countries." Red Cross, 2006
Thank you
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