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DELMAS DIARRHEAL OUTBREAK 2007. The Delmas Municipality is a Water Service Authority since 2003. The current water demand of Delmas is 16mg per day. 10 boreholes and a Rand water pipeline supplies water to the Municipality.
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The Delmas Municipality is a Water Service Authority since 2003. • The current water demand of Delmas is 16mg per day. • 10 boreholes and a Rand water pipeline supplies water to the Municipality. • Delmas is situated on a dolomatic area and the water is abstracted from a quiver.
DIARRHEA OUTBREAK OF 2003 & 2005 Recommendation • 1993 recommendation was that a portable treatment works must be built. • In 2005
HEALTH • A number of Diarrhea cases were received by the Hospital,Clinics and General Practitioners are with the highest of 90 patients/day. • Lack of proper Chlorine dosing prior to the 14 October 2007 • 11 admissions have been reported. 8 already discharged with 3 children still in hospital up to the 20 November 2007. • Up to date 1003 cases have been reported. • A comparison with the 2005 outbreak is being developed by Dept of Health and would be ready by Friday the 23 Nov 2007
ERADICATION OF BUCKETS • 360 house holds have been completed and families have been moved • 1000 houses have been allocated by Department of Local Government and Housing. • All houses came with water borne system. • And the remaining buckets are all in the informal settlement.
IMMEDIATE INTERVENTION • 7 DWAF staff are assisting Municipality on a daily basis taking samples and monitoring chlorine • A commitment of R750 000.00 has been made by DWAF to appoint a management contractor to enhance present capacity. • Premier has committed funding for Rand Water pipeline and completion of purification works amounting to R78 million. • An un-disclosed amount was made available to start with the processes for the current financial year. • A long term sustainability is proposed by the province in establishing Management Contracts at District Level to deal with water and sanitation issues.
Water Quality InvestigationApproach • To ensure that the water currently reticulated is safe. [30th Oct – 16th Nov] • Then to investigate whether drinking and/or resource water are responsible for the outbreak. [2nd Nov – 16th Nov] • To make recommendations for improvements to Authority [16th Nov & 3rd Dec] • To make Regulatory Recommendations to the DG & Minister. [3rd Dec 07]
Observations of 1/11 Micro Results • On the 1st of November sampling was done again to determine safeness of reticulated water. • No microbiological contamination could be detected; Test results complied with SANS 241:2006. • This prompted DWAF to make the statement that thus far nothing was found to implicate the tap water to be unsafe for human consumption.
Observations: Production boreholes’ Quality • A-field heavily contaminated (fecal pollution) • Same in 1993; same in 2005; same in 2007. (As reported after the outbreaks in ’93 and ’05) • However it was detected; Levels of pollution did increase over the years due various possible sources. But most prominent would the overloading of the waste water treatment plant.
Observations: Chemical Quality • Since it was reported that the tap water frequently displays some brown discolouration, it was the initial thinking that the high levels of Iron would be detected. However iron levels were well within acceptable limits according to results • Manganese proved to be problematic and this led to the conclusion: responsible for frequent discoloration of water. Of Aesthetic nature and not regarded as heath risk. • Mercury levels in A3 was beyond SANS limits. (this would be diluted after mixing) • Excessive levels over long term exposure would have an effect on nerves systems. • Arsenic levels: Was reported in the 2006 RQS report. Conventional treatment would be the answer.
University of Johannesburg • The University assisted the Department with the investigation, carrying their own costs. • Their involvement assisted DWAF to take the investigation beyond water. Holistic intelligence is being generated from the analysis data. • Findings will form part of Delmas DWQ Regulatory Report. • University’s involvement will continue; assist to study Environmental Health; Water and Diarrhea Outbreak relationships in Delmas as part of an Epidemiological study. This in an attempt to generate credible intelligence that will assist with interception of contributing factors. Results
University of Pretoria • Dr. Maureen Taylor’s Virology Laboratory was requested to assist with detection of any viral contamination. • A3 sample indicated presence of: • Rota virus • Astro virus • Entero virus (unconfirmed) • B4 sample indicated presence of: • Rota virus (unconfirmed) • Nothing confirmed in the reticulation system. • Tests will be completed by 22 Nov 2007.
Chlorine Levels • The Drinking Water Quality Regulation team assessed chlorine residual results as was recorded by the Municipality. • Since DWAF’s involvement during the outbreak audit sampling was done. Free Cl Records Audit Nov Records
Observations: Cl levels • Insufficient levels of free Cl detected as from Sept 11 2007. • However a constant pattern of low levels of free Cl at points 1 -6. • Constant dosing did take place throughout the system even though insufficient levels were detected for the period 11/9 and 14/10. • Good records were kept by municipality. • Records compare well with DWAF audit sampling over Sept 2007.
Conclusions on free Cl shortcomings • The low levels of chlorine residual indicates that water most probably was the trigger for the diarrheal outbreak. This is supported by: • Wide-spread location of affected residents; • DNA detected of bacteria (in viable state) in reticulation system, which originates from A-filed aquifer. • However clearly not the reason for the continuance of the diarrhea. • Adequate levels prevailed in the system since about 14th October 2007. • The Chlorinated water (Delmas) mixing with the Chloraminated (Rand water @ Eloff) certainly played a role in detected low levels. • Breakpoint Requirement: 0,1mg/100ml Ammonia-Chloramine + 0,2 mg/100ml Chlorine.
Motivation for Expanding Investigation • Why is diarrhea outbreak continuing so long after DWQ has been restored? • Infants normally drink formula mixed with boiled water(?) • Recurrence over the same period of the year (after rainy season) • Perhaps chlorine demand increase over this period; after the rain. • University will assist with epidemiological study which would attempt to answer above-mentioned questions.
Immediate Recommendations to WSA • Chlorine stock and Dosing (including monitoring) should remain a priority. • Resolve the shortcomings with the water mix at Eloff. Might require additional dosing unit. (Rand Water willing to assist) • Additional barriers that include Ozone dosing need to be in place before August 2008. (Introduction of a conventional treatment facility. • Should any insufficient chlorine dosing levels be detected; the Municipality will be obliged to immediately issue a Boil Water notice in accordance with Regulation 5 under Section 9 of the Water Services Act.
