rapid assessment of drinking-water quality in the republic of tajikistan

Table 3.11 Compliance with WHO suggested value for conductivity
a
Broad area a Utility piped supplies Protected springs Total
No. of
samples
Compliance
(%)
No. of
samples
Compliance
(%)
No. of
samples
Compliance
(%)
RRS & Dushanbe 506 99.6 108 99.1 614 99.5
Khatlon 346 100.0 103 100.0 449 100.0
Sughd 410 81.5 60 95.0 470 83.2
GBAO 24 100.0 63 100.0 87 100.0
National 1 286 93.9 334 98.8 1 620 94.9
GBAO = Gorno-Badakhshan Autonomous Oblast. RRS = rayons under direct republican subordination.
Nationally, only 5.1% of all water samples tested were not in compliance with the WHO suggested
value for electrical conductivity (1.4 µS/cm) (Table 3.11). Total noncompliance was greatest in the
Sughd region (16.8%), which may be explained by the “hard” water in the area (i.e. water with high
concentrations of salts, such as calcium and magnesium).
3.4 Overall compliance
The RADWQ project defined overall compliance as the proportion of water samples that met the
WHO guideline values and national standards for thermotolerant coliform count, and for chemicals
such as arsenic, fluoride and nitrate, which are of public health imporftance. In the case of Tajikistan,
however, overall compliance was synonymous with compliance for thermotolerant coliforms and
fluoride, as all water supplies in the RADWQ survey were in compliance with the national standards
or WHO guideline values for nitrate and arsenic (Table 3.6, Table 3.8).
Of the 1620 water supplies tested, 86.9% and 65.9% were in overall compliance with WHO guideline
values and national standards, respectively (Table 3.12). The difference in overall compliance levels
is explained by the fact that the national standard for fluoride is less than half of the WHO guideline
value. In the broad areas or oblasts, compliance with the WHO guideline values was greatest for
water supplies in RRS and Dushanbe (92.0%) and least for those in GBAO (74.7%).
3.5 Sanitary risk factors
In addition to the analysis of microbial, chemical and aesthetic parameters, sanitary inspections were
carried out at all supply points visited during the RADWQ study. Sanitary inspections are visual
assessments of the infrastructure and environment surrounding a water supply, taking into account the
condition, devices and practices in the water-supply system that pose an actual or potential danger to
drinking-water quality and thus to the health and well-being of the consumers. The most effective
way to undertake sanitary inspections is a semiquantitative standardized approach using logical
questions and a simple scoring system. Sanitary inspections are complementary to a water quality
analysis and there is an increase in the power of analysis when both types of data are available.
Sanitary inspections also provide a longer-term perspective on the risks of microbiological
contamination, and thus complements the “snapshot” water quality analysis.
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