The decision-support system will need estimates of the costs of servicing. Using information on average per-capita water use and wastewater generation, and general information on treatment levels for a given type and volume of service, it may be possible to develop guidelines for estimating the cost of servicing growth. Information from asset management studies will also be useful in developing cost estimates for maintaining infrastructure.
One potential decision-support system that could provide estimates of the financial costs of water and wastewater servicing is the Cost of Development Model created for the Municipal Finance Officers' Association. The model, which is still under construction, is meant to help municipalities understand the financial implications of new and upgraded infrastructure, such as water and wastewater treatment plants, as well as major pipes. The model includes both capital and operating costs and allows for the creation of alternative development scenarios.