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City of Roseville March, 2008 Summary of Analysis Table 5 provides a summary of all the data developed in the previous paragraphs, The MCES 11 Surcharge program is focused on the "Inflow" portion of the clear water and the highest costs are associated with this category; however, it is important to consider the infiltration portion as well since both infiltration and inflow result in treatment costs to the community. Using the data included in Table 5, the matrix in Table 6 is developed to prioritize areas for additional work. The various factors were ranked numerically from low to high with the low number reflecting the worst case, so the lowest sum will be the highest priority for additional work. Prioritization Rankin Matrix Area Infiltration/ in-mi PIA Ratio Inflow/ in-mi Sum Priori Net M046 4 2 2 8 3 Meter B 2 1 1 4 1 Meter C 5 5 6 16 6 Meter D 1 4 4 9 2 Meter E 7 1 5 13 4 Meter F 5 3 3 11 ~ Meter G 6 6 7 19 7 Meter H 3 5 6 14 5 Meter Area B is the highest priority for additional work with Q and F next. The un-metered areas were not directly measured but fall into the Net M046 service area which also has a relatively high priority. Meter Area E does not have a high sum but it exhibits a high PIA ratio suggesting inflow sources that may be greater than normal. Rehabilitation in this area may provide greater benefits with respect to the MCES Ill Surcharge that is based primarily on the inflow portion of the Ill situation. V. Potential Ill Sources to consider The flow response demonstrated in Figures 4, 7,9,11,13,15,17, and 19 provide one indicator of the type of Ill sources that can be anticipated in the service area. The type of sources in turn defines the type of further investigative methods that should be considered in the various areas. It is impossible to completely define the sources at this stage of the process but we would anticipate that the sources will be more clearly identified as the investigation effort proceeds. Figure 4 -Meter 046 Flow chart indicates a steep (short duration) spike inflow with the flow remaining elevated slightly 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, This meter area includes the entire community and provides a picture of the overall flow situation. Sub-division of this service area is required to provide additional source isolation. Figure 7 -Meter Area B flow chart shows an immediate sharp spike with the flow remaining slightly elevated for more than a day following the peak event. This flow pattern suggests primarily longer acting type sources such as sump pumps, direct footing drain tiles, or leaking sewer service pipes. Figure 9 -Meter Area C flow chart shows a relatively minor flow spike with almost no long term impact. This pattern suggests a few small direct inflow sources, such as small area drains, low manholes, or a small number of longer acting sources such as some sump pump connections, direct footing drainage tile, or leaking service pipes. Figure 11 -Meter Area D flow chart indicates a sharp spike inflow with the flow remaining 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 Page 8 of 12