Kaduna State of Nigeria has a 1991 population of 4.1 million of which 58 per cent is served with water supply by
Kaduna State Water Board. A State-Wide Water Resources Masterplan is being developed to improve coverage to more than 70 per cent covering a projected population of 7.1 million by the year 2020

Hassan Mohammed (6734642)

Nasser Yakubu (7219340)

English

Loughborough University Institutional Repository

F   FINANCE AND MANAGEMENT: MOHAMMED and YAKUBU24823rd WEDC Conference Durban, South Africa, 1997Towards affordable water supplyHassan Mohammed and Nasser Yakubu, NigeriaWATER AND SANITATION FOR ALL: PARTNERSHIPS AND INNOVATIONSKADUNA STATE OF Nigeria has a 1991 population of  4.1million of which 58 per cent is served with water supply byKaduna State Water Board. A State-Wide Water Re-sources Masterplan is being developed to improve cover-age to more than 70 per cent covering a projected popula-tion of  7.1 million by the year 2020.Paying for waterUntil recently, water supply in Nigeria was regarded as asocial service and, therefore, Government provided theinfrastructure and gave subvention in form of cash ormaterial to State Water Agencies (SWAs). In most cases,communities are charged for only a fraction of  the O&Mcosts.Things are changingHowever, with on-going awareness campaign being inten-sified for consumers to realise that fund for providingpotable water must be generated from the volume of watersold, things are changing. As such Kaduna State WaterBoard (one of the 37 SWAs in the country) has beenoperating as a commercial entity, since 1993, paying fornearly all its operational expenses from internally gener-ated revenue.The ideal modelWith cost recovery in mind, it is clear that new watersupply schemes need to be essentially low cost. The re-cently commissioned Zonkwa Regional Water Supplyscheme is seen as a model for affordable water supply bothin terms of capital and running costs. Of special interest isthat this model is a result of a reviewed concept for aproject which has virtually been shelved. Also, this expe-rience becomes very important in the light of the elevennew water schemes proposed in the new Water ResourcesMasterplan for the State.Zonkwa regional water supply schemeThis water supply scheme is financed under the WorldBank funded First Multi-State Water Supply Project.The Project was conceived in 1976 to be a regionalscheme supplying water to the towns of Zonkwa, Manchok,Samaru, Zangon Kataf and all villages en-route. Theproject has a design population of 122,400. Maximumdaily demand for the scheme was determined as 12,868 m3/d  or 4.71 MCM (million cubic metres)  per annum.Initial conceptZonkwa is sited on a basement complex formation withgenerally poor ground water potential insufficient to meetthe demand of the population. For this reason there is anurgent need for piped supplies from surface water sources.Hydrological investigation revealed that River Kwasauis the only nearby source of surface water which can beenvisaged for development. The river has a catchment areaof 22km2. Surface runoff records from a gauging stationat Zonkwa were available from 1973. Characteristic dis-charges of 9.53 MCM annual mean and 4.9.MCM monthlymaximum were obtained.The result further revealed that River Kwasau is not aperennial river and ,therefore, it was concluded that thebase flow is unreliable to support a direct river abstractionand that an impounding reservoir will be ultimately re-quired.Impounding reservoirThe anticipated raw water demand of the Zonkwa was tobe made available by construction of an earth dam onRiver Kwasau to store any flows in excess of demandduring the rainy season for use during the low/dry flowseason.Monthly inflow/outflow budget was simulated alongwith sediment load calculation, and the gross storagecapacity of the reservoir was determined as 3.45MCM.The safe yield of the reservoir was determined as 18.67m3/day.Treatment processesBased on the above concept and the result of the chemicaland bacteriological analysis of the raw water, a conven-tional water treatment plant of 536m3/hr (12,868 m3/yr)was proposed having the following treatment processes tomeet the demand of the project area in year 2005:• Aeration• Floculation• Clarification• Rapid gravity filtration, and• DisinfectionThese processes require the extensive application ofAlum, Lime, Sodium alginate and Chlorine.The projected capital cost of the proposed scheme wasfound to be beyond the limit of the loan and the operationcost beyond the affordability of the population because ofF   FINANCE AND MANAGEMENT: MOHAMMED and YAKUBU249the agrarian setting of the community. Hence, the need toreview the concept  was initiated by the World Bank.Reviewed conceptChange of raw water sourceThe new concept was based on the discovery of a spring(Kajim Spring) at the town of Manchok (35km fromZonkwa) which is capable of meeting the required de-mand. The yield of the spring was investigated to confirmits reliability to meet the demand of the project area to theplanning horizon (year 2005).A safe yield of 17,280 m3/d (720 m3/hr) was establishedwhich is just slightly lower than that of the reservoir in theinitial concept. The reliability of this source discarded theprevious concept of using an impounding reservoir forabstraction.Raw water qualityWater from Kajim Spring was sampled for Chemical andBacteriological analysis at two different Laboratories. Thetest reports confirmed the presence of E. Coli apart fromthat they concluded that the water was of very goodquality, very soft with low levels of minerals and nutrients,and non-aggressive.The results of the parameters tested were all withinacceptable limits of the World Health Organisation (WHO)recommended guidelines. But the presence of E.Coli hasrendered the water unfit for direct human consumption.Treatment processesThe use of sand filtration and precautionary disinfectionwere therefore the only treatment processes applied. Thisdevelopment has resulted in savings both in terms ofdevelopment of treatment plant infrastructure and opera-tion cost.The elimination of the use of Alum for coagulation andLime for pH correction in the treatment processes is veryvital due to the cost of this chemicals in developingcountries. This is especially significant, noting that thesetwo chemicals alone constitutes about 40 per cent of theBoard’s overall operating cost in 1996.Construction costThe costs of construction of abstraction and treatmentunits for both concepts are compared to determine themost affordable to the consumers. Table 1 below showsthe estimated costs of the components.The change in raw water source has lowered the capitalcost by 56 per cent. The community is therefore on a betterfooting to repay the loan which has to be recouped from thesale of water.Chemical costAluminium Sulphate, hydrated lime, sodium alginate andchlorine were all envisaged to be applied in the treatmentof raw water in the initial concept. But the reviewedconcept has chlorine as the only water treatment chemicalto be applied. A comparative cost of treatment for the twoconcept is reviewed to determine the most affordable to thecommunity as shown in Table 2.The annual cost of water treatment for the reviewedconcept has proved to be only 19 per cent of the initialconcept.Energy costThe total power requirement of the initial concept wasprojected to be 325Kw/yr while that of the reviewedconcept was estimated at 240Kw/yr. The cost savings wasworked out to be 20 per cent of the initial concept.Average incremental costTwo alternatives have been analysed from economic per-spectives to determine the most affordable option for thecommunity. In this last stage, attempt is made to work outthe average incremental cost of each concept.Loan maturity period (World Bank) – 25 yearsInterest rate – 15% per annumCapital recovery factor – 0.15470Unaccounted-for-water – 30 per centExchange rate – 1USD$  = N82Below is a comparison of equivalent annual costs for thetwo alternatives:Initial conceptCapital recovery cost = $3,731,364.00Annual chemical cost = 36,472.00Annual energy cost = 73,125.00Total annual cost = $4,001,697.00Reviewed conceptCapital recovery cost = $1,640,284.00Annual chemical cost = 36,472.00Annual energy cost = 52,875.00Total annual cost = $1,729,631.00The Average Incremental Cost of both schemes werecalculated from above parameters to be $1.15/m3 for theComponentEarth damRaw water IntakeTreatment plantTransmission/ reticulation mainsService  reservoirsTotal cost ($million)Table 1. Comparative construction costsCost ($ million)Initial concept11.100.4603.8806.5102.17024.120Reviewed conceptNil0.3642.8795.9701.39010.603F   FINANCE AND MANAGEMENT: MOHAMMED and YAKUBU250Initial and $0.49/m3 for the Reviewed concept. The tariffnow required to break even is N58/m3 instead of N136/m3for the initial option. That is, of course, if the communitywill directly bear the cost without cross-subsidy.Other costsWith the reviewed concept, other economic costs to thecommunity  associated with the environmental impact ofsiting and construction of large reservoirs have also beeneliminated. The overall benefits of this project to a commu-nity who have waited for over 20 years without safe watersupply is very high indeed.Cost recovery initiativesWhile ensuring that water is affordable and available tocommunities, the Board is at the same time looking atmeasures to ensure effective cost recovery. Such include apolicy which implies that new projects (like Zonkwa) areprovided with Water Selling Kiosks (WSK) so that thosewho cannot afford house connections can buy directlyChemicalChlorineHydrated limeAluminium sulphateSodium alginateHydrated limeChlorineTable 2. Annual cost of treatment chemicalsQuantity(tons)9.494.22831.447.19.4Amount ($)Initial36,47218,84095,6543509,42036,472197,208ReviewedNilNilNilNilNil36,47236,472from licensed vendors. This is to ensure that revenue iscollected directly from users instead of  from Local Gov-ernment accounts as is the case with Public Stand Posts(PSP).ConclusionToday, the Zonkwa Water Supply Scheme has seen thelight of the day mainly because there was willingness on thepart of the donor (The World Bank) and KDSWB to seekfor low cost solutions.  This has not only made the projectpossible but the community will now pay only 43 per centof the annual cost of the initial option.If this trend continues, the newly proposed Water Supplyschemes will mean cheaper water and better service cover-age for the population of Kaduna State.One lesson learnt from this experience is that low costalternatives are always available as long as there is thewillingness to pursue them by all parties concerned.BibliographyWAPDECO, September 1990, Kaduna State Water SupplyRehabilitation Study, Nigeria.PARKMAN-SAMAILA, June 1994, First Multi-State, De-sign Report, Nigeria.PARKMAN-SAMAILA, 1997, State-Wide Water Re-sources Master Plan for Kaduna State, Draft Report,Nigeria.HASSAN MOHAMMED, Chief Engineer, Kaduna StateWater Board of Nigeria.NASSER YAKUBU, Senior Engineer, Kaduna State WaterBoard of Nigeria.

Towards affordable water supply

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Towards affordable water supply

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