Basin Size Optimization Forecasts Savings of $190 Million for PRASA
Puerto Rico Aqueduct and Sewer AuthoritySan Juan, Puerto Rico
The Puerto Rico Aqueduct and Sewer Authority (PRASA) faces large construction costs in order to improve its sewer systems to comply with the Clean Water Act. Using databases of flow, rainfall and GIS data, and a graduated flow monitoring basin optimization process helped to minimize estimated costs of subsequent SSES, rehabilitation and construction work. The process allowed PRASA to choose the lowest apparent overall cost approach for characterizing and improving 52 collection systems Island-Wide. Central components of the analysis were: 1) graduated basin size monitor placement and optimization, 2) basin size versus RDII isolation estimates and 3) a cost-effectiveness database. Using the three tools in combination as described herein, PRASA was able to reduce the estimated projected costs of follow-on work by an estimated $190 million while simultaneously focusing rehab on basins with excessive rainfall dependent infiltration and inflow (RDII) and on areas with capacity limitations. Presented herein is a process to optimize flow monitor site selection, tie the monitoring more tightly to capital improvement programs, boost quality of dynamic model results, increase the probability of highly effective rehabilitation and minimize follow-on SSES and construction scopes and costs. Graduated Basin Size selection can create multiple benefits that not only increase quality but also decrease costs. Benefits include:
• Increased model quality
• Lower short-term SSES costs
• Improved effectiveness of sewer rehabilitation
• Reduced long term CIP costs. Source: WEFTEC 2009 Proceedings
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Posted: July 6th, 2010 | Filed under: 100K-500K, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Flow Monitoring, Improved Operation | No Comments »
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