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City of Roseville March, 2008 pump connections, direct footing drainage tile, or leaking service pipes, This is a relatively large service area and some of the flow pattern may be due to a long transit time in the system. Additional area sib-division will be necessary to further isolate the sources and evaluate the area. Figure 13 -Meter Area E flow chart is somewhat confused due to debris on the transducer during some of the meter period. However; the rainfall day data do indicate a sharp short duration spike with flows returning to near normal levels after the runoff event. This flow pattern suggests primarily quick acting direct inflow sources such as catch basins, area drains, low manholes, or roof drains. Figure 15 -Meter Area F flow chart indicates a short duration quick spike in flow with the flow remaining slightly elevated for an extended period of time. This flow pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with some longer acting sources such as sump pump connections, direct footing drainage tile, or leaking service pipes, Figure 17 -Meter Area G flow chart indicates a short duration quick spike inflow with the flow remaining slightly elevated for an extended period of time. This pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with a small number of longer acting sources such as some sump pump connections, direct footing drainage tile, or leaking service pipes. Figure 19 -Meter Area H flow chart indicates a short duration quick spike inflow with the flow remaining elevated for an extended period of time. This pattern suggests primarily longer acting sources such as some sump pump connections, direct footing drainage tile, or leaking service pipes. VI. Preliminary Conclusions The peak flow analysis indicates that there is inflow in each of the eight temporary metersheds and it is anticipated that a similar situation occurs in the "unmetered" areas (not included in the 2007 temporary metering programs that are ultimately tributary to the MCES Meter M046. The September 18, 2007 event resulted in a possible "flow exceedence" event at meter M046. There are no long term average flow data at the temporary meter locations so flow exceedences cannot be calculated. The calculated P/A ratios can be a quick indicator of a potential "exceedence" area. Areas B and E have calculated PIA ratios of 3.33 which is greater than the overall City ratio of 3.25. These areas are smaller and would have typically have a higher P!A ratio but they are out of line with the other similar sized service areas in the City. The work completed to date is the first step identifiying and removing the ill in the collection system. Additional investigation will be necessary to further identify sources and complete rehabilitation to reduce the Ill flow rates. Based on the flow response, it is anticipated that private property type sources including sump pumps, direct foundation drains, and possibly deteriorated sewer service connections provide a portion of the inflow in each service area; however, in Meter Areas D and H these connections may be the major contributors. In Meter Areas B, D, E, F, and G the flow response suggests that there are some direct type connections in addition to some private property sources. Note that Meter Area D appears in both the long term and direct inflow categories due to the large service area at this time. Meter Area C appears to have a much smaller amount of inflow than any of the other metered areas. The current data are not sufficient to specifically identify sources for the inflow, however, they can be used to plan subsequent data collection and inflow investigation efforts. Page 9 of 12