raindrop newsletter july 1992 v7 rainwater harvesting bulletin

8/9/2019 Raindrop Newsletter July 1992 v7 Rainwater Harvesting Bulletin

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RAINDROPRainwater Harvesting BulletinJuly 1992 Volume 7

Focus on Thailand:Thai Jar Program Reaches M illions of Fam iliesRainwater harvesting (RWH) is more widespread inThailand than any other country in the w orld. The level ofeffort and results are astounding: more than 10 million 1-2m3 (1 m3 = 1000 liters) rainwater jars and hundreds ofthousands of 6-12 m3 rainwater tanks have been constructedin the last seven years.Most households innortheastern Thailand,where the program hasbeen most successful,have at least one andmany have severalrainwater jars.

The Thailand RWHprogram is considered tobe one of the mostsuccessful examples in theworld of how potablewater supplies can beincreased on a nationalscale. It is one of the fewcountries to even approachthe International DrinkingWater Supply andSanitation Decade targets for rural water supplies.

Village craftsmen assemble a star fruit mold rainjar.

The Thai jar program is the most successfulexample of a country-wide RW H program thatsignificantly increased rural water supplies.The successes of the program are largely a product ofstrong governmental support at all levels, combined with theefforts of nongovernmental organizations (NGOs), theprivate sector, and grassroots initiatives. It is noteworthythat the government of Thailand, in addition to a variety ofstandard water supply technology options, chose to wholeheartedly promote rooftop rainwater harvesting as a practical and cost-effective way to increase water availability inunder-served rural areas.

Major Lessons LearnedThe rapid growth of the Thai program was madepossible by a combination of factors that may be relevant toother countries interested in developing broad, as well aslimited-scale RWH programs. Governmental commitmentand support has been very strong; and national targets andobjectives were clearlydefined. Rainwater harvesting is a long standingtradition in Thailand, andthe annual rainfall is highrelative to many otherregions of the world. Thedemand for improved watersupplies in rural areas wastremendous, and thisdemand led to the emergence and growth of manyindependent jar makingmicro-enterprises. Thailandalso experienced a period ofnational economic growthand an increase in privateaffluence during the life ofthe program which made iteasier for families to invest in RWH technologies.Several jar and tank designs were tested and used on alarge scale in the early stages of the program. Problems didoccur with some of these designs, particularly the use ofbamboo-reinforcement, which had been widely publicizedas successful. This experience underlines the need to applypreliminary findings with caution, and when design problems are uncovered, these need to be communicated widelyso others do not repeat the same m istakes.

As in many other water and sanitation projects worldwide, health and hygiene considerations were not built intothe planning and implementation of the project.Not surprisingly, the achievement of targeted increasesin water supply has not been accompanied by a correspond-continued on Page 3 (Thailand)

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From the Editor's Desk What is the RHIC Netw ork?This edition features the spectacular growth of rainwaterharvesting in Thailand, where over ten million householdrainwater harvesting systems have been implemented in thepast seven years. The magnitude of the Thai RWH expansion is our strongest proof to date that rainwater can becomea significant regional water source. The conditions whichsupported that unparalleled growth in rainwater harvestingsurely include the laudable leadership, commitment, and thewillingness to innovate of the Thai governmentFor other countries striving to increase potable watersupplies for under-served households, important lessons canbe learned from the Thailand achievements, as well as fromthe problems that still confront the Thai rainjar program.The most notable difficulties stem from poor water handlingpractices which mean that water-borne diseases have notdropped to lower levels in spite of the increased rural watersupplies. We are not surprised to learn that, without effective education to promote sanitary water handling and betterhygiene practices, many Thai rainjar owners have simplycontinued their traditional patterns of water handling.The most common practices are lack of hand washingand use of unsanitary water dippers to draw water from thestorage jar. Part of the problem is lack of appropriatetechnology but a very significant part is the inadequatevillage-level understanding of hygienic water handlingmethods. The addition of an effective water tap to therainjar seems an obvious and simple solution. However,there are problems stemming from the additional cost of the(usually imported) tap, difficulty of repair and repair partssupply, and increased vulnerability to water theft or accidental loss.For those households with rainjars not equipped withtaps, a water handling improvement may mean using a"dedicated" water dipper which has a handle that is notemersed in the water and which is only used for transferringwater from one container to another. However, this wouldnot be practical forremovingwater from large rainjars.The effective resolution of these water hygiene issueswill not likely be obvious or the same for a ll locations. It isclear that these are socio-technological issues requiringchanges in both technology and behavior. Progress willrequire the use of significant resources and the collaborativeinvolvement of householders and community leaders.Carl J. Lindblad serves in a variety of sectors in interna-tional development. In addition to rainwater harvesting, hisexperience includes agricultural extension and training,postharvest technologies, and small business development.

The RHIC Network membership currently includes 763individuals and institutions from more than 101 countries.These members are involved in a range of RW H activitiesfrom grass-roots project implementation to university basedresearch. The names and addresses and basic informationabout each member's rainwater harvesting activities arefreely accessible on the RAINCOLL computer data base.RHIC Network membership has increased from 74 in 1986to the present total. Membership is open to any individual ororganization who wishes to join, and has no dues or fees.The chart below shows the geographic distribution of RHICNetwork Members.

GEOGRAPHIC DISTRIBUTION OF NETWORK MEMBERS

LETTERS FROM THE NETWORKDear RHIC,Thanks for the very informative RAIND ROP . Next year, ou rgraduate students will assist me in preparing a report onrainwater harvesting in N igeria, and I will send it to you. W ehave large undergraduate and postgraduate programs inwater resources in both teaching and resea rch. Kindly assistour efforts however you can.Dr. Boniface EgbokaAnambra State University of TechnologyPMB 01660 Enugu, NigeriaDear RHIC,Thank you for sending past issues of RAINDROP andinformation on the RHIC Network which I found very u seful.Nepal has huge prospects for RW H to reduce arduous dailytreksfo rwate r by wome n in the hills of Nepal. Our Centre ForRural Technology in Kathmand u is also interested in studying and disseminating cost-effective technologies for rainwater harvesting in rural areas, for which your information isheartily acknowledged.Regards,Ganesh Ram Shrestha, Executive DirectorCentre For Rural TechnologyPOBox 3628Tripureswore, Kathmandu, Nepal

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Thailand (continued from Page 1)ing drop in water-borne and sanitation d iseases. It is nowrecognized that social and health considerations are essentialin order to achieve the health impacts that can result fromimproved access to clean w ater supplies. The government ofThailand is now placing more of its attention on improvinghygiene and health education on a national scale.RWH is Thai Tradit ionVillagers in rural Thailand have harvested rainwater formany generations, long before the national-level promotional campaign for rainwater storage in the 1980 's, butost families did not collect sufficient quantities of rainwater or enough to last through the dry season. Traditionaltorage containers have typically been 20-40 liter clay or100-400 liter ceramic jars.Thailand has a high annu al rainfall com pared with

man y countries In the world, averaging 1,000-2,000mm per year.Thailand enjoys a h igher than average annual rainfallith countries in other parts of the world, with anl of 1,000-2,000 mm per year. Eighty-fivethis annual rainfall occurs during the six monthsthe rainy season.The rainfall in the southern region is higher than in thethe country, more than 2,000 mm per year. Evenonth dry season, there is still about 50rainfall per month.

NGOs PioneeredIn early 1985, the Ministry of Interior outlined itsves for the nationwide Rainwater Jaron Program at a meeting of governors and headsices of government agencies. The governon with locally-active N GOs, initiatedthe construction of the first several millionjars and tanks.Implementation of the program is largely in the handsas program, as the program directors for eachtheEach district has its own methods for getting operatingthe major source for the program budget hasfrom he w ell-established Rural Job Creation Project.included the ProvincialfromMembers of Parliament, theinistrative Organization, as well as thenon-profit organizations.

The success of the Thai RWH program results fromfavorable rainfall patterns as well as stronggovernm ental and popular support at all levelsincluding NGOs, comm unity-based Initiatives, andthe private enterprise sector.

A num ber of multilateral and bilateral agencies alsoprovided funding, including UNICEF and the government ofAustralia. Research, especially on jar and tank designs andrainwater quality, has been carried out by K hon KaenUniversity; Mahidol University; and the Asian Institute ofTechnology.Rural Areas TargetedSeventy-two percent of the 57 million people inThailand live in rural areas. These areas have typicallylacked access to clean and adequate drinking water supplies.The overall goal of the national program was to provide therural population with 5 liters/capita/day (lcpd) of cleandrinking water and 45 lcpd for domestic use by 1990.In order to meet this goal, the government set twomajor objectives: to provide one 2,000 liter jar (enough for2 lcpd) to households lacking adequate drinking waterstorage by the end of 1987, and for each household toacquire two additional jars, enough for 5 lcpd by 1990.Jars B ui l t by Users and Micro-enterpr isesOriginally the jar construction program w as to befinanced by a revolving fund, using start-up money from thegovernment Villagers were to be involved in the m anagement of these revolving funds. However, the programexpanded so rapidly that the administration of the revolvingfund could not keep up with the demand, and these fundswere generally not used.

Many districts provided construction materials, tools,and training, and people contributed labor to construct theirown jars under the supervision of experienced technicians.Khon Kaen University and government agencies providedtechnical assistance in the preparation and dissemination ofconstruction manuals, and in training technicians. Jarconstruction centers were established and located either inindividual villages or in villages that served wholesubdistricts.It was initially envisioned that villagers would constructtheir own jars. However, as the program evolved, a numberof other options emerged, and the private sector becamevery much involved in rainjar construction. In somedistricts, groups of villagers were paid to construct therainjars and deliver them to households, often with fundingfrom the Rural Job Creation Program.continued on Page 6 (Thailand)

RAINDROP JULY 1992 PAGE 3 UBRTAHYTHCP O B ox 93190 , 2 5 0 9 A D T HE HA GUET e l . : + 3 1 70 30 689 80Fax: + 31 70 35 899 64B A R C O D E :LO :


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Water and SanitationHygiene Techniques for RWH

by J. Hari KrishnaAs rainwater harvesting becomes increasingly populararound the world, it is important that adequate attention begiven to m aintaining and improving the hygiene quality ofthat water for human consumption. There are a few relatively simple techniques that are generally suggested:Roof MaintenanceMaintaining smooth roof surfaces can increase thewater quantity collected and reduce the possibilities fortrash, dust, moss, and other material to accumulate on theroof and contaminate the runoff. The roof or collectionsurface should not be painted with a product which containslead or mercucy. Tree branches and electric or telephonewires should not be allowed to hang over the roof becausethese provide a place for birds to perch and their defecationcontaminates the roof.Screen InstallationOne or m ore screens should be installed to prevent trashand other material from washing into the cistern. Anymaterial that accumulates on the screen(s) should beremoved regularly to allow free flow of water and to reducecontamination.First Flush DevicesThese are used to divert the first flow of rainwaterwhich flushes off the roof or collection surface. Severaltypes of first flush devices have been developed, rangingfrom simp le overflow type diverters to complex automaticdevices. Th e appropriate choice should be based on localconditions and available resources.Cistern CleaningCisterns or other rainwater storage containers should beemptied and cleaned at least once yearly, ideally jus t beforethe beginning of the heavy rains. Any debris orfinesludgeshould be scooped and/or flushed out of the cistern. If theremains of any small animals are found in the cistern,repairs should be made to screen off openings to prohibitfurther entry. Sweep thoroughly to loosen and remove alldirt. The entire interior surface should then be well scrubbedwith a 20 percent solution of common laundry bleach inclean water and left for at least 30 minutes before re-filling.ChlorinationOrdinary household bleach may be used to disinfectcistern water. Up to 4 ml of liquid bleach may be added per100 liters of water. Chlorination treatment can be done

every four to six weeks to maintain disinfection. Cautionshould be exercised because excessive chlorination not onlyadversely affects the taste of water but is also dangerousbecause it may cause cancer. It may be practical to treatonly the small quantities of rainwater stored in the homerather than the whole rainwater tank, so that if over treatment occurs the batch can be used for washing withoutmajor waste or risk.BoilingWhere fuel is available, boiling water five m inutes willdisinfect it for drinking. However, boiling will not rid waterof some disease carrying micro-organisms which must befiltered out of the water. Also, boiling with charcoal orwood may be costly both econom ically and environmentally.Dr. J. Hari Krishna is the Director of the Water ResourcesResearch Center at the University of the Virgin Islands, St.Thomas, VI00802, USA.

Cholera UpdateWhat causes cholera?Cholera is an acute enteric bacterial infection characterized by severe, watery diarrhea, vom iting, and consequentdehydration. Death can occur in a matter of a few hours ifno rehydration treatment is provided. Infected persons mayshow no symptoms, or only mild ones, but they can stillspread the disease to others. The route of transmission forcholera is simple: the disease is acquired by the ingestion ofan infectious dose of cholera vibrios, usually from watercontaminated with the feces of an infected person. Cholerais considered the classic waterborne disease, but transmission through foods prepared with contaminated water orhandled in an unsanitary m anner is also common. Raw orundercooked seafood from contaminated coastal waters canalso transmit the disease. This strain of cholera can flourishin a saline environment

How to avoid cholera?The best way to slow the spread of cho lera~and othermore common diarrheal diseases-is through the use of acombination of standard hygienic behavior and appropriatesanitation and water supply technologies. In practical termsthat means disposing of all feces in a sanitary ma nne r-through latrines, waterborne sewage systems, or otherappropriate sanitation systems. For this barrier to beeffective, 100 percent adherence is required. Even a minorbreakdown can have wide ramifications because of the wayRAINDROP JULY 1992 PAGE 4


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Water and Sanitationcholera bacteria multiply and persist in the environmentLatrines must be appropriately designed, well maintained,and used by entire families and communities. If choleracannot be kept out of the environment, then the bacteriamust be avoided or destroyed through water system disinfection. If the municipal water supply becomes contaminated, then people can avoid the bacteria only by drinkingsafely-bottled or boiled water. Sanitary storage and handlingof rainwater also can provide a source of potable water safefrom cholera infection. However, sanitary handling ofdrinking water from whatever source requires effective handwashing using soap. In areas where cholera already existsthere is a very high risk of passing cholera pathogens fromcontaminated hands to communal drinking cups or waterdippers. To avoid ingesting cholera contaminated rainwater,boiling or chlorine disinfection is strongly recommended,however extensive boiling of water can be prohibitivelyexpensive and/or environmentally unsound.

Hawaiian RWH Users React toQuality Surveyby Todd Boulanger

There are approximately 25,000 households on the Island ofHawaii (the Big Island) using rainwater collection systemsto provide their potable water supply needs. The lack ofaffordable housing with access to water supply infrastructure makes rainwater catchment systems a frequent topic ofdiscussion. Following the recent periodic volcanic eruptionswhich have caused an increase in sulfur dioxide in theatmosphere, the Centers for Disease Control (CDC) and theHawaii State Department of Health cooperatively initiated asurvey of rainwater catchment users on the Big Island. Thepurpose of the survey was to investigate the relationshipbetween acidic rain water, building materials containinglead, and the elevated levels of lead found in catchmentwater, and to identify households atrisk.A follow-up studyselected 194 at-risk participants from the 3000 householdsoriginally studied, although the results have not yet beenmade public.Under a separate research project funded in part by theUS Geological Survey, Dr. Yu-Si-Fok and graduate researchassistant Todd Boulanger (Department of Urban andRegional Planning, University of Hawaii and Manoa) havesurveyed the same 194 at-risk households to gain moreinformation about the age and physical characteristics of theconstruction materials used for roofing and rainwatercatchments on the Big Island. The survey also attempted toidentify the adaptive measures being taken by rainwater

using householders to reduce water contamination risksidentified by the CDC study.The survey results indicate that rainwater users aregenerally aware of the CDC warnings about the risks of highlead levels. The most common response to improve waterquality has been to bring in drinking water, typically fromcommunity standpipe sources, or to purchase commercialwater filters. However, a typical problem w ith waterfiltration systems is appropriate replacement of the filterfollowing therecommendedschedule.Manyfilterpurchasers have been convinced byopportunistic filter salespersons' claims of complete successin lead removal. Water filter sales promotions offer freetests of water quality to determine if there is water contamination, however there is no similar analysis of w ater afterthe filter hasbeen purchased and installed. Regulation ofwater filter sales has been recommended to prevent fraudulent claims as well as substandard filter quality. In December of 1991 a local law was passed obliging water filtercompanies to provide accurate information on what the filterwill and will not remove from water.

The University of Hawaii survey found that Big Islandhousehold rainwater harvesting users often make substandard provisions to safeguard water from contamination bybirds, animals and insects. The survey found few RWHusers who provided screens over down spouts or adequatecistern covers. The most common cistern cover is wovenpolyethylene fabric draped over the tank opening. Manyhouseholders harvesting rainwater have branches, TVantennas, telephone wires and the like hanging over the roofspace providing birds with a place to roost and defecate,contaminating the catchment surface.Over the next year, the University will provide localrainwater users with information on maintaining rainwaterquality, appropriate construction materials, and sizing ofcatchment area and rainwater tanks. Also, the County ofHawaii Board of Water Supply now provides an educationalvideo comparing various types of waterfilterson the localmarket. The EPA has recommended that carbonfiltersarenot effective for removing leadfromhousehold drinkingwater. The Clean Water Board in Hawaii also attempts toinform filter users that if not properly used and maintained,filters may provide an environment highly conducive to thegrowth of micro-organisms that can cause diarrhea andother water-borne diseases.Todd Boulanger is a Graduate Research Assistant at theDepartment of Urban & Regional Planning, University ofHawaii at Manoa.



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Thailand (continued from Page 3) rainwater in certain parts of the country, especially in thenortheast region.As the program evolved, micro-enterprises beganto produce good quality rainjars at pricesaffordable to millions of rural Thai families.

Other d istricts subcontracted small jar-making factorieswhich sprang up and developed into successful micro-enterprises in many provinces. These v illage micro-enterprises began producing 2 m3 jars for U.S.$22.00 (1988)including delivery. The current (1992) rainjar price is aboutUS$40, but even at thisprice, villagers could savevery little by constructingthe jars themselves.Estimates vary on thenumber of jars built bycommercial enterprisesbut these probably amountto over half the totalnumber constructed. Mostare built by v illage-basedcompanies which produceup to 30 jars per day.Completed jars aredelivered to customers onsmall trucks that can carryup to six jars at a time.High CoverageAchievedDrinking water supplycoverage for Thailandbased on the intermediatecriteria of 2 lcpd was 26percent in 1981. Thisincreased to 70 percent in 1986, and reached 76 percent by1988. The rapid coverage increases have been primarily dueto the Thai Rainjar Program. Using the 2 lcpd interimcriteria, 65 percent of the rural population are provided withdrinking through RWH. If the 5 lcpd criteria is used, 36percent ob tain adequate quantities of drinking water throughRWH.Implementation More Rapid Than PlannedIn 1985, the program set the ambitious target ofconstructing 6 million rainjars by June of 1987 as a 60thbirthday gift for the venerated King of Thailand.Not onlywas the goal met, but by 1992, over 10 million rainwaterjars were in use. The rapid development of the program isdue to a num ber of factors. T here was a large felt need forincreased water supplies, and a preference for the taste of

Ferrocement rainjar with tap and plastic tube to draw off water.

In 1985, the national program set the ambitioustarget of constructing 6 million rainjars in 2 yearsas a 60th birthday gifttor he Thai King. By 1992,there were over 10 million jars in use.Adding to the conditions that favored the program 'ssuccess were Thailand's period of national economic growthand increased private affluence during this time period.Subsidized and affordable cement was readily available, andmany skilled artisans alreadyhad experience in constructing traditional rainwater jars,who readily learned how toconstruct the new jarmodels. There were alsomany local engineers,

technicians, and administrators with a commitment torural development programs.While the constructionof rainwater jars was muchmore popular and rapid thanoriginally planned and led togreatly increased access towater supplies, there werealso some disadvantages tothe rapid growth of theprogram.Initially many jars werebuilt without design featuresto enhance health impacts,such as taps, drainage plugs,and lids. Development ofguidelines and disseminationof information on proper operation and maintenance of thesystems, and large scale health education did not begin untilrecently. Rationing of collected rainwater has not alwaysbeen effectively followed, so many families still rely oncontaminated sources during part of the year.

RWH Most Popular in Northeast T hailandImplementation of the program has been more successful in some parts of the country than others. Forty percent ofthe jars built are in the northeast region, while only 13percent are in the southern region. Fewer jars were constructed in the south because alternative sources of watersuch as shallow wells are more readily available, and thetaste of rainwater is less appealing in the south.continued on Page 7 (Thailand)



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(continued from Page 6)A major study found that in northeast and central5 percent rated rainwater as their preferredsouth, where ground water isilable, shallow well water is often preferred to rainwaterany cite the unpleasant salty taste of rainwa

to the adjacent oceans. Rainwater collecth, but smaller jars are morebecause rainfall is higher and less erratic in therequirements so that onejar is usually sufficient

In the early 1980s, more than 50,000 bamboo reinced cement tanks were constructed. Many of these failedto fungal, termite and bacterial attacks on the bamboosuccessful. In fact many of the bamboouse, but have been strengthened

An interlocking brick design was also developed, butlater abandoned since the workmanship and skillsecausehai rainjar models have proven to be successl on a large scale, major research is no longer beingdevelop new jar or tank designs.Several RWHjar and tank designs were tested andused In the early stages of the program. Majorproblems occurred with bamboo-reinforced Jars,

which initially were publicized widely as asuccessful innovation.The jar design which has been promoted by thethe top to prevent contamiwater, and a drainage plug

However, jars made commercially usuallyhave taps or drainage plugs and are often soldnets and lids.This is at least in part because jars with taps andplugs are considerably more difficult to constructort Some villagers also prefer jars without tapstaps may leak and are difficult to repair, andwaste water. If taps aret used, then access to water is usually by bucket or bywater with a hose. Program authorities havelid and the net to be supplied by jar owners,does not occur.The Thai rainjars are made of sand and cement mortar,1-2 m3. Jars can be constructedolds including home-made jute bagricehusks, or standardized Ministry of

Health molds including the 54 piece cement mold and starfruit iron or cement mold. After the cement is cured, the jaris slowlyfilledwith water. Sour leaves are recommended toclean the jars before they are used to take away the smelland taste of cem entLarger rainwater tanks for individual households aretypically 3-5 m3 capacity and constructed with iron reinforcement. The Ministry of Health tank design includes atap, drainage plug, overflow outlet, incoming water tube,bypass tube, and a lid. Construction is typically carried outusing a standard mold at the villager's house. Thousands oflarger tanks (6-12 m3) have also been constructed atschools, clinics, temples, and private homes.Rainwater Quality AssessedA major study, published in 1989, was undertaken byKhon Kaen University1 in which stored rainwater wasanalyzed bacteriologically for pathogens. The results fromthe study of rainwater quality of outside rainwater tanks andjars showed that only 40 percent of samples met WHOstandards for total bacterial counts of drinking water, 66percent met standards for total coliforms; and 57 percentmet standards for fecal coliforms.The route of contamination was investigated byevaluating the quality of rainwater samples collected fromthe roofs and gutter systems, and outdoor and indoor storagecontainers. It was found that poor water handling was amajor cause of secondary contamination of rainwater.Despite the problems found with water quality, the studyconcluded that rainwater is still the safest and most economical source of drinking water available in most ruralareas.Unsanitary water handling was found to be a majorcause for secondary contamination of rainwater.Jar designs often did not include a water tap orcover making sanitary water handling nearlyimpossible.

Rather than trying to cchieve the idealistic goal ofmeeting WHO safe drinking w ater guidelines, researchersadvocated it would be more beneficial to concentrateresources on improving sanitary water handling practices toreduce secondary contamination of rainwater.Concerns have been raised that uncovered rainwaterjars can lead to increased breeding of mosquitos, whichspread dengue fever and m alaria. However, research carriedcontinued on Page 10 (Thailand)

'Khon Kaen University. Evaluation of Rainwater Quality: HeavyMetals and P athogens. Khon Kaen, Thailand. June 1989.



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Technology NewsPrevent Cracks in FerrocementTanks

by Lloyd BelzAre you having trouble with leakagefromsmall cracks inyour ferrocement rainwater tanks? When the tank is put intoservice, does it leak, leaving a white stony deposit thatforms below the crack? The problem may be very simple toavoid, especially if this problem occurs mostly on the sideof the tank that receives most of the afternoon sun.The sun is the number oneenemy of the ferrocementtank builder. Carefully examine the tanks you have built tocount the cracks in relation to the position of the afternoonsun, which is the hottest of the day. If the sunny side hasmore cracks than the shady side, you can improve your nextcistern by taking steps to protect thefreshplasterfrom heheat of the sun.When a layer of ferrocement plaster dries, the newlayer of plaster will not stick to it properly. The two layerswill not "h eal" together. These "unhealed" layers of piasterare not sealed together and are likely to form a leak. Thebest way to avoid this problem is to work in the earlymorning or evening and keep the tank in the shade andmoist all of the time while under construction.There is also the absolutely essential after-constructioncuring process to be concerned about. This is a completelydifferent m atter than the sun drying of fresh plaster. Thetank m ust be kept damp or wet for at least seven days afterconstruction to allow the cement to cure and gain strength.However, if the layers have a dry spot between them wherethey have not "healed" together, keeping the curing plasterwet will not correct this faultLloyd Belz is a RHIC Network member and the owner ofBELZ Engineering and Construction Company, with officesin Hilo, Hawaii; Tonga, South Pacific; and 20706 S.E.Lewis and Clark Highway, Camas, Washington 98607 USA.

New Water Tap DesignFor low-income families and communities, water taps maybe an expensive addition to the rainwater tank. In rural areasof Nepal, the piped water supply had many standpost tapsthat were broken by users who were not familiar with themechanical devices. Poor quality of the water taps anddifficult spare parts supply added to the breakage problem,with average tap service life as little as nine months. Thenew tap design can be locally manufactured in metalwork-ing shop s, and consists of a tooled brass plug that is inserted

into the end of a standard water outlet pipe that hasalsobeen machined with a matching taper. The plug is pulledout when water is needed, and subsequently pushed backinto the pipe to stop the flow. A chain attaching the brassplug to the pipe prevents loss or theft. The advantages of theplug tap are that it has no m oving parts and does not wear,and is easy to use. It can also be used vertically or horizontally, and can be a direct replacement for an existing brokentap, requiring only a short pipefittingwith tapered end anda corresponding plug. Its use is limited by high waterpressure, and if the plug is pushed in too hard it can bedifficult to open, but users learn easily.Although this tap is not yet known to have been used inrainwater jar designs, it may be appropriate for trial implementation. The tap was developed by Jon Lane ofWaterAid. For more information, contact Jon L ane,WaterAid, POBox 4231, Kathmandu, Nepal. Fax 977-1-418-479.Alternative Uses for RWH

by Dan CampbellRainwater harvesting systems have traditionally been usedas potable water supply sources for drinking, bathing, andcooking. However, in highly urbanized areas of somecountries where the piped water supply is being overtakenby demand, rainwater systems are being adapted foralternative uses such as irrigation, and toilet flushing. Inassociation with the National Taiwan Ocean University andWater Resources Research Center, Show-Chyuan Chu andYu-Si-Fok have conducted research on such alternativerainwater uses in Japan, Singapore, United Kingdom, andthe United States, and have found that these can be botheconomically viable and conserve potable water.In Japan, piped water supply systems are spread widelyover the country serving about 95 percent of the population.But in urban areas such as Tokyo, many office buildings andindustries are clustered together, with resulting watershortages in times of draught. During heavy rainfall,flooding can occur due to the high level of runoff. Somemodern Japanese buildings are being equipped to harvestrainwater for storage in tanks built in to the ceiling space intheir underground structure.Dan Campbell is the WASH Librarian and InformationOfficer. He organized and manages the RHIC Network aRAINCOLL database. He has an extensive background inwater and sanitation in international development, espe-cially in Latin America.



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RHIC Network Updateh RWH Systems Conference

ext international RWH conference will be held inast Africa during August 1-6,1993. The confertheme w ill be "Participation in rainwater collection formunities and sustainable development."nce objectives will be to:

Identify social, cultural, and economic problems andconstraints that influence effective participation in thedevelopment, promotion, and use of RWH systems.Exchange lessons learned and experience gained in thedevelopment and use of various low-cost rainwatercatchment technologies.Identify factors that affect RWH system sustainabilityand replicability.the potential for expanded rainwater use inrural and peri-urban areas.Share experience from research and development ofRWH systems design, construction, and water quality.Exam ine factors that influence die effective role ofwomen in development and sustainability of RWHsystems.

Interested participants are invited to submit, bys of papers related to the conferencesubmitted not later than December 31,Full papers must be submitted by March 31,1993.correspondence to: John Mbugua, Internationale on Rainwater Cistern Systems, PO Box 56,ya Fax: 254-2-716-254

Second National Kenyan RWHWorkshopThe second national Kenyan workshop on rainwaterharvesting systems will take place in Nairobi, Kenya, fromAugust 30 to September 4,19 92. Part of the program is a 2-day excursion to see the many types of RWH projects in therural Machakos and Kitui districts in Eastern K eny aContact Erik Nissen-Petersen, POBox 867, Kitui, Keny aFax: 740524.Regional Asian IRCSA Seminaron RWH SystemsA one week seminar on RWH systems is scheduled forOctober 4-10 ,199 2. Professor Isao Minami is organizing theseminar. He can be contacted at The D epartment ofAgricultural Engineering, Faculty of Agriculture, KyotoUniversity, Kitashirakawa, Sakyo, Kyoto City, Japan.

News From AfricaUNICEF Kenya and the Kitui Integrated DevelopmentProject (KIDP) have now completed m ore than 500 RWHtanks and 500 VlP-latrines at 300 primary schools serving150,000 students in eastern Kenya Each RWH tank has avolume of 46 m3 (46,000 liters), providing up to 115 m3 ofwater from the two annual rainy seasons. The tanks willsupply students with about 2 liters of clean drinking waterevery school day. The cost is US$1 per 1000 childrenamortized over 30 years.In Tanzania, two new RWH projects are underway, onewith Swedish financing which is building several types ofRWH tanks and the other with UNDP/ILO financing whichis building RWH tanks and subsurface dam s.

News From The Pacific IslandsA recent USAID-funded study found that almost 90 percentof the larvae of mosquitoes that transmit dengue fever in Fijiare produced in abandoned iresand uncovered RWHstorage containers. Recomm endations were for comm unity-based control efforts, relying on the strong local tradition ofcommunity participation in clean-up efforts, particularlyamong women.



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Thailand (continued from Page 7)out by the Thai-Australia Project found that rainwater jarsonly rarely contain mosquito larvae, larvae were found inonly 0.2 percent of jars. Much more frequently, smallercontainers inside the house were found to be the site ofmosquito larvae. Covering jars with nylon or wire mesh hasbeen recommended, which would also keep out lizards androdents.Widespread Health Impacts Not Yet AchievedWith RWHThe achievement of target increases in water supply hasnot been accompanied by a corresponding drop in water andsanitation related diseases. In fact, little has been achievedin implementing effective hygiene education programsnecessary to achieve the health impacts that can result fromthe provision of clean drinking water.

In the push to achieve broad dissemination ofRWH technology, health and hygieneconsiderations were not essential parts of theprogram design or implementation.There are a number of reasons for this. Implementingagencies have been directed by technical specialists withlittle training and background in social processes. Successhas been measured by the number of jars built, in partbecause it is much easier to count jars and tanks than tomeasure a behavioral change such as improved waterhandling practices.Also, not enough is understood about behavioralpractices which can have an impact on health (for example,water handling , or hand washing) and there is little understanding of what villagers consider "clean" or "healthy" andhow such concepts varygeographically and ethnicallythroughout the country. iHs/difficult to handle water in ahygienic way given the design of many existing jars, sincemany jars were not constructed with a tap, a drainage plug,or provided with a lid or net, as recommended in theMinistry of Health designs.Water from the collection jar is often transferred to asmaller jar and a communal and multi-purpose dipper is

used to get the drinking water from these smaller jars. Thisadded water handling step leads to contamination of thewater, especially when hands are not washed before usingthe dipper. Many villagers do no t yet understand thatimproper water handling can lead to a variety of illnesses.Health and Education Reach the NationalAgendaSocial and health considerations are crucial to anywater supply program if it is to have lasting health impacts.

The government has recently started to move towardsdeveloping a re-focused program, shifting from an emphasison construction to a combination of construction andsupport programs. A Sanitation Action Plan has beendrafted which includes a niajor health education component,based on social considerations, such as a need to understandthe differing attitudes, beliefs, and sanitation behaviors ofrural people in all regions of thecountry.The focus of national plans is shifting from how toimplement and finance the rainjar program on a nationalscale to improving water quality and health through betteruse, operation, and maintenance of systems by encouragingthe use of health-related design features (such as taps, nets,and lids) and more effective hygiene education. Thairesearch activities are shifting to measure impacts of theprogram, and to develop effective hygiene educationstrategies.

77?0 focus of national priorities is shifting from jarconstruction to improving water quality andhealthespecially through more effective hygieneeducation.

It is expected that this new focus will mean fundamental changes from the "top-down" and earlier passiveeducational approaches which relied heavily on distributingprinted materials and using village loudspeakers. The newstrategy will be more "bottom-up" with more active person-to-person communication, reinforced by the use of massmedia, including television and radio. The p lan also calls forgreater involvement in active health education by allcommunity groups, including religious leaders, villagehealth volunteers, craftsmen, youths, school teachers-andspecial input from women in the community.For schools, a long-terrn goal of improving sanitationand personal hygiene has been set. Teachers will explainpractical hygiene and sanitation practices, and basic waterand sanitation facilities w ill be provided to schools. At thecommunity level, the extension skills of the Ministry ofPublic Health staff will be targeted so they w ill be betterable to communicate with villagers, understand localpractices, and develop programs which are meaningful andnecessary for villagers.

As an example of the new emphasis on improvinghygiene, the Thai-Australia Project and the Ministry ofHealth produced materials for primary schools in northeastThailand based on a rainwater jar cartoon character. Thishealth education program is being extended and hopes toreach 75,000 primary school students. If successful, theprogram will be expanded to other provinces. Postercompetitions are also being held and the best posters on howcontinued on Page 11 (Thailand)



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fromPage 10 )use rainwater jars are being printed and used as part of

uture DirectionsImproved relations and communication with neighborthe Thai rainjar program to Laos, Burma anddia. Rural poverty in these countries will howeverit difficult to achieve rapid replication of RWH.Links between Khon Kaen University and Waterientiane, Laos are promising ofRWH promotion. Over a quarter ofillion Cam bodians are living in U.N. camps in easternmore than 80,000 rainwater jars have beenMany refugees could help dissemithe technology in Cambodia once repatriated. Technid by Khon Kaen

Nepal and the Philippines.

The size and scope of the rainjar construction programunprecedented example of what is possible

Thai rainjar cartoon character is happy to have a coverand screen, tap, outlet drain, and solid foundation.

iKlaleq

Ti Vrfnr '

nsr,w anr K nhramtaltM

to achieve in a relatively short time to increase access towater supplies through RWH.The rapid growth of the program demonstrates that thedemand for improved access to water supplies was tremendous. Private businesses were able to produce rainjars at aprice affordable to many rural families, and helped theprogram grow rapidly.The major challenge that remains for the Thai JarProgram is to maximize the potential healthImpacts of this far-reaching program.

Problems with some of the earlier designs, especiallythe bamboo-reinforced jars and tanks, highlight the need tocommunicate researchfindings,both the positive and thenegative, widely and rapidly. This is especially criticalwhen design problems are uncovered in a new technology,so that others using these designs are alerted and faultydesigns are not replicated elsewhere.Recent studies have pointed out problems with rainwater quality, and much of this contamination is due tounsanitary handling of stored rainwater. In the push toachieve high levels of coverage, health and hygiene considerations were not developed as essential parts of the designand implementation of the rainjar construction phase.Now, families need to learn how to improve the waysthey operate and maintain their rainwater system s. Wellplanned and effective health education and mass mediacampaigns, especially on hygiene practices and waterhandling, are essential to improve drinking water qualityand health. The major challenge that remains for the ThaiJar Program is to maximize the potential health impacts ofthis far-reaching program which has been remarkablysuccessful in so many other ways.This article was prepared by Bonnie Bradford, a publichealth consultant specializing in water and sanitation,housing, and the environment, in collaboration withNongluk Tunyavanich, AssociateProfessor, MahidolUniversity, Faculty of Social Sciences and Humanities,Salaya, Nakorn Pathom, Thailand; and John E. Gould,University of Botswana, Department of EnvironmentalScience, Gaborone, Botswana. The article also draws upona number of published documents about the Thailandprogram.

:SJUMTW-



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Information Resources Expand the RHIC NetworkConcrete Roof TileThe Swiss Center for Appropriate Technology (SKAT) is aninformation center on sm all-scale clay and cement roofingtile manufacture. Low cost, durable roofing m aterials thatcan be locally manufactured may be a key component of asuccessful RWH program, especially where the only optionis imported metal sheet roofing. SKAT now distributes freecopies of two four-page leaflets about small-scale manufacturing of concrete roof tile in India and in the Republic ofKiribati in the Central Pacific. The Indian documentincludes information on cost, maintenance, and marketingissues , and gives useful information about the regionalcenter in New Delhi. The Kiribati document discusses a flatroof tile design made with a low water content cement sandmix that was developed to cope with poor quality coral sandcausing major problems in tile strength and high porosity.For free copies of the leaflets and a free publications catalogcovering 350 titles on Building M aterials, Energy and RuralWater Supply, contact: SKAT Bookshop, Tigerbergstrasse2, CH-9000 St. Gallen, Switzerland

Membership in the RHIC Network is free of charge andopen to any individual or organization interested in rainwater harvesting. Membership includes access to theRAINCOLL database and being added to the mailing list forRAINDROP.The RAINCOLL database is intended to serve all RHICNetwork members, and access to its extensive collection ofpublications and data is available to any m ember. RHICcurrently receives 20-30 requests per month for technicalinformation. If you request information, please be asspecific as possible concerning the information you arewant, and address your request to Dan Campbell at RHIC,WASH Operations Center, 1611 North Kent Street, Room1001, Arlington, VA 22209, USA.

The wider the RHIC network is, the more informationand experience there will be to offer Network members.You can help expand the Network by passing on to RHICthe names and addresses of other individuals or organizations who may wish to be nominated as Network mem bers.Thank you for taking the time!

Rainwater Catchment Systemsfor Household Water Supply, byJohn Gould, 57p., 1991.This new publication reviews state of the art RWH systemstechnologies. Using case studies from Asia, Africa, andAustralia, major technology and program issues are reviewed. Successful strategies and approaches to projectplanning, implementation and evaluation are examined,with information regarding cos ts, financing mechanisms,and water quality. The report is available from: ENSIC,Asian Institute of Technology, POBox 2754, Bangkok10501, Thailand. US$20 air-mailing included. US$12 forrequests from developing countries.

RAINDROPis available inFRENCH!

M9G>WATER AND SANITATION FORHEALTH PROJECTFor additional information about activities and reports highlighted in this issue, contact:

WASH Operations Center1611 North Kent Street, Room 1001Arlington, Virginia 22209 USA

Water andSanitation for Health Project, ContractNo. DPE 5973-Z-00-8081-00, Project No. 836-1249. Sponsored by the Office of Health, Bureaufor Research and Development, U.S. Agency forInternationalDevelopment, Washington, DC 20523.


raindrop newsletter july 1992 v7 rainwater harvesting bulletin

Documents