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businesses, and then evaluated each neighboring community's water quality and water availability to supply Gem Lake's water demand. 2.1 Gem Lake Water Demand To determine Gem Lake's water demands, the City's population and land uses must be considered. Because a water system must be built to supply future demands. Gem Lake's ultimate population and land uses were considered in this feasibility study report. 2.1.1 , Population Based Water Demands Based on review of Gem Lake's Ramsey County tax parcels, as can be seen on the map in Appendix B, the City has 216 residential tax parcels including seven vacant residential lots. Although one of these vacant lots is owned by the same owner as an adjacent residential tax parcel with two residences on the same parcel, the vacant lot is not assumed to be developed so it is estimated that the ultimate number of single family homes in Gem Lake will be 216 with 209 of those currently existing. This is slightly less than the 229 single family homes estimated in the 2006 feasibility study, which was based on land use acreage and minimum lot acreages. It is not assumed that any of the existing single family home tax parcels will be divided into smaller parcels. Based on the 2020 Census, the population of Gem Lake is 528 with 199 households, which is an average of 2.65 persons per household. Using a more conservative value of 3 persons per household, the ultimate population of Gem Lake based on 216 homes is estimated to be 648 and using an estimated demand of 100 gallons per person per day, the ultimate residential average day demand (ADD) is estimated to be 64,800 gallons per day (gpd). Although the residential per capita demand is recommended by Minnesota Department of Resources to be estimated at 75 gallons per person per day or less, Gem Lake residential properties tend to be larger than the average residential property in the Twin Cities metro area and are thus expected to have an above average per capita water usage. The estimated values of 3 persons per household and 100 gallons per person per day used in this study are the same as was used in the 2006 feasibility study. Using a ratio of maximum day demand (MDD) to ADD, called the maximum day peaking factor, of 3, the ultimate MDD from single family homes is estimated to be 194,400 gpd. A maximum day peak factor of 3 was also used in the 2006 feasibility study and is on the high end of typical maximum day peak factors in the Twin Cities metro area. In addition to the estimated 216 single family homes, the City informed SEH that a high density residential complex could possibly be constructed on a mixed use parcel south of County Road E. To be conservative, it was assumed that all mixed use parcels south of Country Road E and north of Hoffman Road could be converted to high density residential parcels and demands were calculated based on land use as discussed in Section 2.1.2. 2.1.2 Land Use Based Water Demand As discussed above, demand calculations for high density residential land use parcels were based on the land use method, as were the mixed -use parcels, recreational open space parcels (golf course); and the public/institutional parcel. Water demand calculations for each land use type can be seen below in Table 1 and the ADD of gpd per acre values used are consistent with typical industry values and values used in the 2006 feasibility study. FEASIBILITY STUDY UPDATE City of Gem Lake, MN Page 2