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Final Report <br />City of Paris, Texas <br />Wastewater Collection System Capacity Analysis <br />Table 1- Basin Priorities Ranked by Replacement and Rehabilitation Costs <br />Priority Ranki <br />ng by Compound De <br />fect Flow and Replacement Costs <br />Rank <br />tllgh <br />Moderate <br />- L <br />OW = <br />1 <br />PR13 <br />PR08 <br />PR01 <br />PR09 <br />PR16 <br />PR23 <br />2 <br />PR30 <br />PR14 <br />PR02 <br />PR10 <br />PR17 <br />PR25 <br />3 <br />PR06 <br />PR22 <br />PR03 <br />PR11 <br />PR18 <br />PR07 <br />4 <br />PR20 <br />PR26 <br />PR04 <br />PR12 <br />PR19 <br />PR28 <br />5 <br />PR29 <br />PR27 <br />PR05 <br />PR15 <br />PR21 <br />Alternative Projects <br />The effects of flow reductions on the replacement requirements through various <br />rehabilitation options were determined. Replacement program costs were <br />evaluated for the following scenarios: (1) No Rehabilitation (2) Rehabilitation of <br />all defects in the 5 highest rated basins (3) Rehabilitation of all defects in the 10 <br />highest ranked basins and (4) Full Rehabilitation of all defects. <br />Piping System Investment Requirements <br />By using the costs associated with Scenarios (1) and (4) we have established the <br />impact of repairing none of the defects and replacing inadequately sized lines and <br />repairing all of the defects and replacing inadequately sized lines. Scenario (1) <br />establishes the highest replacement costs associated with performing no <br />rehabilitation work. Scenario (2) was the preferred option as it was fou.nd to <br />represent the most reasonable combination of replacement and rehabilitation <br />costs. Scenario (4) was the scenario that considered rehabilitation of all defects <br />and the associated replacement costs. This was by far the highest cost scenario <br />that was evaluated. The respective combined costs for each scenario were <br />approximately, $7.5 Million, $6.9 Million, $7.0 Million and $10.2 Million. <br />Summary of Findings and Recommendations <br />Much valuable knowledge was gained regarding the overall operational character of the <br />collection system. An up-to-date map of the system, along with an associated database <br />was prepared. Additionally, a collection system model was constructed, calibrated and <br />used to determine the effects of various improvement programs on the system. <br />Using industry standard hydraulic modeling techniques combined with detailed flow <br />reductions predicted by each rehabilitation program, a least-cost program to minimize <br />overflows was established. <br />By reviewing the hydraulic capacity of the system under design storm conditions and <br />under varying combinations of replacement and rehabilitation progams, an optimal <br />4 <br />