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• based on updated probability tables. Therefore, the July 1 event exceeded typical storm system design standards in the Metropolitan area. It is apparent from this analysis that even if the system had been designed to accommodate a 100-year event, structural inundation still could have occurred in some areas of the City. C. Results of Engineering Analysis From the 57 storm water issues/complaints, a definition of"problem area" was developed. When flooding caused damage to property that cost money to the homeowner/business, it was considered a problem area. If flooding occurred to a depth of less than 2 feet and no cost to the homeowneribusiness, it was not considered a problem area. Therefore, for the purposes of this report, flooding that inundated a garage was considered a problem while flooding of an open area with no structures involved was not considered a problem. Utilizing this definition, the original 57 storm water issues/complaints were either resolved without further study, removed from consideration if they did not meet the above problem criteria, or included as one of 13 individual study areas if they did meet the above criteria. These 13 problem areas areshown in the attached figure. In general, the type of damage and estimated cost of damages associated with each problem area fell into one or more of the following categories: • Basement/structure flooded • Flood water ponded against structure, but structure not flooded • Storm sewer backed up The 13 problem areas were analyzed to identify the problems and to generate preliminary recommendations to address the problems. In order to address or correct these problems, the following improvement alternatives are typically available: • Construct additional storm sewer capacity to carry water away from problem area • Construct improvements to existing storm sewer (i.e. add flap gates, catch basins) • Provide additional storm water storage • Provide emergency overflow for storm water • Flood proof structure • Purchase structure and remove from flood prone area • Study the problem further • Do nothing The improvement alternatives listed above were reviewed and the most cost-effective physical alternative available to address the problem was selected. Very preliminary cost estimates to construct improvements in each problem area range • from, "do nothing until redevelopment occurs"to $1.8 million. A preliminary cost estimate to construct all necessary improvements to address the flooding in the 13 problem areas is estimated at$5.7 million. This estimate is based on providing 100-year, City of St.Anthony WSB Project No. 1065.11 Pave 4 4