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<br />J2s1 <br /> <br />includes preparation of the routing fields, existing and future land use <br />information, and cost information to be used for estimates of relief <br />sewer construction costs. <br /> <br />2. Calibrate Model. Prior to any analyses, the model will be <br />calibrated against the flow data from flow monitoring activities. <br />Calibration will consist of modifying the estimated initial response <br />time to rainfall until computer calculated peak flows and travel times <br />are within acceptable agreement with monitored data. Calibration will <br />be performed for a I-year storm. <br /> <br />3. Analyze at Current Conditions. System hydraulic capacity analyses <br />will be performed for current growth and 1/1 conditions. Analyses will <br />be performed for peak dry weather, and I, 5, 10, 25, and 50 year storm <br />events. The model output will include a comparison of peak system flows <br />at each condition, percent capacity used, and an estimated parallel and <br />replacement relief sewer size and cost. These analyses will not include <br />a detail analysis of each line to determine relief options and or <br />probable design relief sewer sizes. <br /> <br />4. Analyses at Future Flow Conditions. System hydraulic capacity <br />analyses will be performed for future growth and 1/1 conditions without <br />rehabilitation. Future growth analyses will be performed at one <br />selected level or protection for year 2005, 2015, and ultimate growth <br />conditions. Design curves for future growth areas will be developed for <br />planning purposes. ~ <br /> <br />H. Cost-Effect Analysis <br /> <br />1. Generate Typical 1/1 Elimination Curve. In order to perform the <br />cost-effectiveness analysis (CEA), an 1/1 elimination curve is required. <br />The elimination cost curve will be based on information collected during <br />the field survey activities and related project experience. The <br />elimination cost curve will show the incremental unit 1/1 removal cost <br />for levels of elimination from zero to 100 percent removal. <br /> <br />2. Select Analysis Storm Event. An 'analysis storm event must be <br />selected to perform the cost-effectiveness analysis. The hydraulic <br />analysis completed under Task VIII can be used as a guide in selection. <br />Selection of the analysis storm will be made in consultation with the <br />OWNER. <br /> <br />3. Perform Cost-Effectiveness Analysis. A preliminary cost- <br />effectiveness analysis will be performed to determine if, and to what <br />level, it is cost effective to eliminate a portion of the 1/1. The <br />preliminary cost-effectiveness analysis will be based on relief sewer <br />costs from the capacity model output, available infiltration/inflow <br />(I/I) source data, and treatment capital and operation and maintenance <br />costs provided by the OWNER. If additional field inspection activities <br />are performed, 'the cost-effectiveness analysis should be updated with <br />the new data. This update is beyond the scope of this project. <br /> <br />06/02/93 <br /> <br />A-13 <br />