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considered in this study which may make a joint system financially feasible though some would need to be upsized. Reducing the length of interconnections by removing the City of Columbus from the joint utility is likely to reduce the annual repair and replacement costs for a joint utility under Option 2 and for Columbus itself under Option 1. The main difference between Options 1 and 2 is the distribution of repair and replacement costs for watermain. This difference may be insignificant if maintenance costs are distributed according to city population. However, fully developed communities with aging watermain will have disproportionately higher maintenance costs in the near term under Option 1 than the newer cities with larger populations and newer systems. Under Option 2 the growing communities would end up subsidizing watermain repair and replacement costs for the older cities with smaller populations if costs are distributed by population. This is an incentive for older cities with little forecasted development to join the joint utility, and ultimately leads to mutual benefit for all cities involved—growing communities benefit by obtaining access to the older cities' supply and storage as they continue to develop. In return, they purchase access to those assets and help to fund the repair and replacement of aging infrastructure in the smaller cities. This mutual benefit would be reduced if distribution infrastructure is not jointly owned as in Option 1. For this reason, Option 2, joint ownership of the entire water system, is likely to be more equitable for all cities involved than Option 1. 9.3 Benefits of a Joint Utility (Option 1 and 2) 9.3.9 Future Watermain Efficiencies For the distribution system, the joint system would need specific locations of large watermain installed to facilitate interconnections and combine the separate distribution systems that now exist. It is assumed that the majority of this cost would be fully paid for by developers per current policies of the growing cities. Some larger diameter connecting watermains needed to access existing infrastructure in fully developed communities may be shared trunk main costs that cannot be fully billed to developers but should still allow for real savings. Creation of a joint utility is not expected to provide a cost savings in large trunk watermain, but the total amount of large diameter looped watermain installed within each community should be reduced to some extent. The reason for this is that each community would typically have a large diameter main looped around its perimeter to ensure adequate fire protection to the fringes of the community. Two communities bordering each other would each have larger diameter mains running roughly parallel to each other in relatively close proximity. If the communities are joined together, only a single main would be needed to accomplish the same level of fire protection. The large diameter main would continue across community borders rather than turning to follow a border thus reducing the need for parallel mains. Furthermore, when looking at member cities, the amount of required additional watermain could be reduced if the City of Columbus is not included in the joint utility or if the communities were realigned based on proximity and existing interconnections to other large communities such as the City of Blaine. 9.3.2 Supply and Storage Savings Additional advantages of a joint system include the ability to share water supply and storage under Options 1 and 2. As each city is currently required to provide firm well capacity to meet peak demand, a joint system would eliminate the need for up to seven (7) future wells and generators. Furthermore, wells could be sited in areas with greater productivity, to target certain aquifer capture zones, or areas with less connectivity to surface contamination. For example, Hugo is anticipated to need 5 additional wells before 2030 due to expected development. Figures A9 and Al depict the bedrock geology and location of impermeable clay layers. In Figure A10 it can be seen that although Hugo has relatively productive wells, the clay layer is spotty within Hugo's Joint Water Utility Feasibility Study 32