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manhole walls. By contrast, inflow is water discharged into a <br />sewer system and service connections from such sources as roof <br />leaders, cellar, yard, and area drains, foundation drains, <br />cooling water discharges, drains from springs and swampy areas, <br />manhole lids, storm waters, surface run-off, street wash waters, <br />or drainage. Although some infiltration and inflow is inherent <br />in any constructed sewer system, the objectives of reducing <br />excessive infiltration/inflow are: <br />1. The elimination of untreated wastewater bypasses and <br />overflows . <br />2. A lower total cost of treatment works. <br />3. Avoidance of unnecessary treatment works capacity <br />construction. <br />4. The reduction of total wastewater volume which must be <br />treated. <br />The 1981 I/I analysis, completed strictly for the southwest <br />Orono collection system, determined that 32% of the total flow <br />was infiltration/inflow. <br />The study found that two districts within the study area <br />were subject to potentially excessive I/I. These districts were <br />analyzed from the cost effectiveness of transporting and treating <br />the wastewater versus the location and rehabilitation of I/I <br />sources. It was determined that the cost of locating and <br />rehabilitating the I/I sources would exceed the cost to transport <br />and treat these flows. Based on the conclusions of the report, <br />the following recommendations were made: <br />1. That the City of Orono initiate and carry cut a <br />continuous I/I identification and correction program. <br />2. That the City promote public awareness of the <br />illegality and consequences of foundation drains discharging <br />to the sanitary sewer system. <br />18