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System Modeling: Prior to perForming any actual modeling, background information <br /> (pertinent files, data, records and other miscellaneous information) will be closely reviewed. After <br /> discussions with the City staff regarding possible elevated tank sites and during the evaluation of <br /> each possible site, TIC will run the model of the City of Decatur's water distribution system to <br /> evaluate the impact of a tanlc at each site during normal and m�imum design demands. The sys- <br /> tem model will be valuable in determining the hydraulic effects of locating the tank at each of the <br /> sites under consideration, and evaluating the system pressures during the normal and maximum <br /> demands. The model will also be valuable in evaluating the effect of an elevated tank at each site <br /> with system demand changes. (This phase will be completed by CDI and TIC.) <br /> Two Tanks: Unlike most engineers who will look at what the system requires, and then make a <br /> simple blanket recommendation(eg:Bui1d a new 2.OMG elevated tank in the south side system.) , <br /> TIC will take a second look at the options. If the City of Decatur requires a 2.OMG elevated <br /> tank, it may be better for the City to build two I.OMG elevated tanks. The two smaller tanks will <br /> allow for easier future tank maintenance. When the 2.OMG elevated tank would require repaint- <br /> ing (as much as 16 - 20 weeks for complete repainting) or even just routine evaluation, the south <br /> side water system would be back to where it is now: with pressure and storage problems. With <br /> multiple tanks, having one tank empty at a time would only impose a small burden of operating <br /> the system with less elevated storage. Additionally, the construction of two 1.OMG elevated <br /> tanks would allow the system modeling to look at two tanks at different sites — perhaps one tank <br /> at the old south water treatment plant and the other closer to Mount Zion. Also, the tank which <br /> would be located closer to Mount Zion may be able to help solve some of Mount Zion's pressure <br /> and flow rate concerns. The additional cost for two 1.OMG elevated tanks rather than one <br /> 2.OMG elevated tank would likely be less than 15%. TIC's goal is to recommend the best solu- <br /> tions for today's challenges while avoiding tomorrow's headaches. (This phase will be completed <br /> by CDI and TIC.) <br /> Siting the Tank(s): Based upon the results of the system modeling, TIC will work closely <br /> with the City of Decatur to locate an appropriate site. Several issues must be considered when <br /> selecting the tank site. These issues include:� site availability, zoning restrictions, proximity to <br /> appropriately sized water main(s), acquisition costs, soil conditions (foundation costs), site eleva- <br /> tion, availability of electricity, site drainage, accessibility to roads, anticipated community accep- <br /> tance, and tank constructability/maintainability. _ <br /> Once a general location for the tank is determined, TIC will work with the City to determine what <br /> sites are available. Once a group of available sites is determined, TIC will research zoning re- <br /> strictions of each site and the anticipated community acceptance of a tank at each site. Based <br /> upon the results of this research, TIC will review the sites with the City to obtain their input to <br /> "short list" the sites to be considered. <br /> Once a short list of sites has been developed, TIC will evaluate each site from a constructability <br /> standpoint. This would include identifying accessibility of the site for steel delivery, adequate <br /> "lay-down" area for sub-assemblies and equipment required for construction, other structures on <br /> the site, overhead power lines which would require relocation, required ground clearing and/or <br /> 3-3 <br />