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proposed to go online in the summer of 1997. The current water tower in Centerville has a capacity of about 100,000 gallons. There are several different ways to examine water storage needs for a municipality. One method is to provide enough water storage to fight a fire with all wells out of service and without depleting the storage by more than one half. The other half is reserved for meeting domestic demands. The rationale behind this method is that a fire could occur at the same time as a power outage. The fire department would rely solely on the available water storage, as the well pumping capacity would not be available. Using the ISO recommended fire flow rate of 1,000 gallons per minute and a fire duration of 4 hours, the storage requirement is 480,000 gallons. Obviously, this storage volume has never been available to the City, while the community has always been at risk for fires to households. However, as a municipality grows, this method is more practical for calculating water storage volumes because the risk of a fire increases with the number of dwellings in that municipality. Another method to calculate the required water storage volume involves calculating the demand when a fire occurs during the peak period of the maximum day of record. Storage facilities should meet the peak hour flow rate minus the average hourly flow rate of the maximum day demand for a period of at Least four hours. Peak hour demand should be met without depleting storage by more than half, so that a reserve is available for fire fighting purposes. Since data was not available to determine peak hour, a peak hour demand of 2.0 times the average hourly flow rate of the maximum day demand was used. This is typical peak hour ratio for similar communities. For example, the maximum day demand for the year 2001 was projected to 0.949 MGD as shown in the City's Comprehensive Water Plan. The peak hourly demand would be 1.898 MGD. To provide peak hourly demand minus maximum day demand for 4 hours without depleting the storage by more than one half, a minimum of 316,333 gallons of storage is required. For the year 2016, 419,000 gallons of storage is needed using this methodology. Still another way to calculate water storage requires review of the water usage records, and setting the required storage volume equal to the average daily use. Records indicate the average daily use is approximately 70 gallons per person per day. In 1995, the water system had a service area population of 932 people. This results in a total required storage volume of about 70,000 gallons. However, given the current development climate in Centerville, connections to the system should increase rapidly in the next few years. An increase of just 150 connections (3 people per connection) would result in the required storage calculated to be 100,000 gallons. According to the Recommended Standards for Water Works, this method would calculate the storage required for a system that does not provide fire protection. As the above summary shows, there is a current need for the City of Centerville to increase the capacity of the available water storage volume. This could be accomplished through either an interconnect with Lino Lakes to utilize the storage from the Lino Lakes water tower, or through construction of a new water tower in Centerville. Ultimately, both the interconnect and the water tower will probably occur. The interconnect will occur when the city watermain system extends close enough to the interconnect connection point through the sequenced extension of the watermain system based on land development. If the interconnect occurs soon, the City of Lino Lakes is requiring that the City of Centerville have a new water tower in operation within 10 years FEAS - 260.085 -2- 260-085 -11