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.' study, we hilve ilssumed lhilt storage capilcity could be rented from Evans. ^ 4 MG tank could adequately serve Ule City for some time into the future, and 10% of that capac ity ~it)U I d adequdt.c ly serve as surge contro I for the ent i re transmhsioJl 1 ine Systl~lIl. Ten pel"ccnt of the cost of a 4 ~iG reservoir has been added i lito the cos t es t imatcs for the NClJlU\ system. Transmission facilities I"ore sized by using pressure loss due to friction under max imum day demands in the des i gn yeal". The est imated useful 1 He of a steel pipeline is 50 years. A design life greater than 20 years was not used because the initial cost of the system would be increased, and the transmission lines \"Iould have a large amount of excess, unused capacity during the first fel~ decades of operati on. It is true, however, that the capac I ty in 1 arge transmission lines can be greatly increased and even doubled by slightly increasing the diameter of the pipe. The resulting increase in construction cost I~ould also be slight in comparision to the total cost of the system. A design life of 10 years has been rejected using this seme principle in reverse. The cost of a 10 year design would be only slightly less than the cost of a 20 year system, The benefits and capacity of such a system \'Iould be greatly reduced, ho~cver. The main transmission lj~e was located to minimi~e the total cost of all branch lines and yet be compatible with geographical restrictions such as lakes, hills and riVel"s. ihis was done by using a weighting method in which largc.water users tend to pull the location of the main line towards themselves. In addition, the location of the source of wilter and the accessibility on public right-of-way \~re taken into consideration. All transmission line costs are based on steel pipe prices with exception to lines 12" and smaller. The price includes a cement coating on the inside, and 15 . .