# Water Supply Systems for Settlements with Arsenic-Contaminated Groundwater--Making the Right Choice
## 3 Results and Discussion
### Comparison of the Alternative Approaches
Each municipality is responsible for their own budgets and their own water supply systems. Politically, the level of cross-municipal cooperation required for the more efficient centralised solutions would in practice be hard to achieve. 2. Even within the municipalities, local politics will often side against the centralised solution. As discussed by [PERSON] and [PERSON] [11], regulators often face difficulty in convincing smaller municipalities to take action in the face of public health risks from drinking water. The costs of upgrading existing water supply systems is relatively straightforward to demonstrate, but in comparison to the easier path of doing nothing, the health benefits of the investment are hard to quantify. In Kanjiza for example, the economic benefits are not uniformly distributed throughout the municipality--the village of Martonos is the only settlement which would pay more in operational costs per capita as part of a centralised system as they would with their own local system. Martonos would, thus, potentially be harder to convince that the public health benefits outweigh the costs. Thus, for the centralised systems to succeed, each settlement would need be included on the municipal water management board, enabling everyone to have a say on how the costs will be distributed and whether water rates would be increased in each settlement to cover those costs. 3. For the localised systems approach, where every settlement has their own WTP, the construction could be easily organised into multiple phases--there is no need to build all the separate WTPs at the same time. On the other hand, the centralised systemsare harder to divide into a phased construction regime and, therefore, represent a significantly larger initial investment barrier than the local supply approach. Considering the relatively limited financial resources of Vojvodina, and Serbia as a whole, at the strategic planning stage, it seems clear that the very considerable benefit in operational costs which is obtained with the centralised supply approach means there is no doubt that all three of these drawbacks should be overcome. Once the strategy decision has been made, the next step would be to enter the development phase, where more detailed feasibilities studies would be required to optimise each system. These studies would include a more in-depth analysis of current and future water demands and predict the requirements for additional wells. In this development stage, a final optimisation of the distribution network would be required. With more precise calculations of operating costs, the development stage would be the final opportunity to include additional settlements in a centralised system. As just one example, by investigating methods for maximising energy efficiency, it is possible that situations could be revealed where increasing the capacity of certain water towers would allow for a larger proportion of pumping to occur at off-peak electricity tariffs, reducing operational costs sufficiently to include previously excluded settlements in the system. In addition to the economic benefits, the centralised approach would help address shortcomings in the supervision and operation of multiple small systems, which would otherwise require significant support from special services and institutions to ensure secure and hygienic water supply. Over time, these systems could be connected in larger units or in a regional system that relies on water sources at a regional level. This approach would enable consumers to be supplied from two or more water sources and, together with the local capacities (microregional and local source), provides the highest level of safety. Overall, socioeconomic conditions play an important role in determining the appropriateness and effectiveness of water treatment in smaller municipalities. It is essential for policy makers and community leaders to prioritise investment in water treatment infrastructure and to address economic disparities that may contribute to inadequate water treatment in some areas.