How Much Will It Cost To Monitor Microbial Drinking Water Quality in Sub-Saharan Africa?

Abstract

Microbial water quality monitoring is crucial for managing water resources and protecting public health. However, institutional testing activities in sub-Saharan Africa are currently limited. Because the economics of water quality testing are poorly understood, the extent to which cost may be a barrier to monitoring in different settings is unclear. This study used cost data from 18 African monitoring institutions (piped water suppliers and health surveillance agencies in six countries) and estimates of water supply type coverage from 15 countries to assess the annual financial requirements for microbial water testing at both national and regional levels, using World Health Organization recommendations for sampling frequency. We found that a microbial water quality test costs 21.0 ± 11.3 USD, on average, including consumables, equipment, labor, and logistics, which is higher than previously calculated. Our annual cost estimates for microbial monitoring of piped supplies and improved point sources ranged between 8 000 USD for Equatorial Guinea and 1.9 million USD for Ethiopia, depending primarily on the population served but also on the distribution of piped water system sizes. A comparison with current national water and sanitation budgets showed that the cost of implementing prescribed testing levels represents a relatively modest proportion of existing budgets (<2%). At the regional level, we estimated that monitoring the microbial quality of all improved water sources in sub-Saharan Africa would cost 16.0 million USD per year, which is minimal in comparison to the projected annual capital costs of achieving Sustainable Development Goal 6.1 of safe water for all (14.8 billion USD).

Figure 1

Overview of our approach to estimate and discuss the costs of microbial water quality monitoring in sub-Saharan Africa. The six countries chosen for the per-test cost estimate were the countries enrolled in the MfSW program. The other countries mentioned in the Figure were selected based on the availability of data. ^aSI Table S5 and Figure 2. ^bTable 1. ^cTable 2. ^dSI Table S2. ^eTable 3.

Figure 2

Cost (USD) of one microbial water quality test in 18 MfSW partner institutions in categories of equipment, consumables, labor, and logistics. The currency exchange rate of 1/1/2015 was used. Institutions have been anonymized, but the countries (Ethiopia, Guinea, Kenya, Senegal, Uganda, and Zambia) are represented by their first letter. The testing method used by each institution is indicated. Specific costs for each institution are detailed in SI Table S5.

Figure 3

Annual number of tests per 1000 people served with piped water in eight countries (black diamonds, Table 1) compared to the best model prediction (dashed line, R² = 0.902, eq 1), which is based on % rural (UN Population Division estimates) and % coverage of piped water (JMP estimates) (SI Table S2).

Figure 4

Estimated annual costs (USD) of microbial water quality monitoring in all sub-Saharan African countries, for piped water (panel a), improved point sources (panel b), and both (panel c). On panel c, the bars indicate the respective fractions of the total costs corresponding to piped supplies and improved point sources. On panels a and b, the population using piped water and improved point sources, respectively, according to JMP’s 2015 estimates, is indicated. The estimated costs of microbial water quality monitoring in sub-Saharan Africa amount to 10 931 000 USD for piped water, 5 106 000 USD for improved point sources, and 16 038 000 USD overall.