The median monthly bill is based on 10 Ccf. As expected, purchasing water results in the highest monthly customer bill. The hybrid approach appears to be the most economical for the customer, while the majority of utilities predominantly use surface water. To classify utilities, RFC assumed the utility must obtain over 75 percent of its water from the particular source to fall in the respective category. If there is no predominant source, the utility is classified as hybrid.
The results of the trending analysis for the impact of water source on the median customer bill show a significant increase in bills for utilities that draw surface and groundwater. Utilities that have water sources of hybrid and purchased water show a lower increase of the median customer bill.