Item 7 - Action MWMC Fac. Plan - Laserfiche WebLink

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Design criteria are based, in part, upon regulatory requirements. The State of Oregon has established a standard that sets the one-in-five-year storm event as the applicable size of rain event that the sewer system must effectively convey and treat without any occurrence of an overflow. This standard was developed with public input, adopted by the State's Environmental Quality Commission, and approved by the U.S. EPA. It applies to all wastewater facilities in the state operating under an NPDES permit. The MWMC 2004 Facilities Plan translates this standard into design criteria, with an objective of preventing wastewater overflows under conditions that do not meet the 5-year storm frequency. While there has been discussion in the public forums that an overflow frequency of once every five years is too conservative, it is nonetheless a legal, regulatory requirement. Since 1995 there have been 7 separate wastewater overflow events from the MWMC system reported to the Department of Environmental Quality (DEQ), as required by the NPDES permit regulating the regional wastewater facilities. The total volume of the overflows associated with these events has been estimated at over 260, 000, 000 gallons. It is important to note that most of the years since 1995 have been part of a drought cycle, and that during this period the Eugene-Springfield area has experienced some of the driest years on record. Modeling done for the Facilities Plan estimates that the peak flows from the Eugene/Springfield system associated with the 5-year storm event will reach 277 million gallons per day (MGD) by the year 2025 (based upon the assumption of continuing rehabilitation of public sewer pipe by Eugene and Springfield). The existing rated peak flow capacity of the Eugene/Springfield Water Pollution Control Facility is 175 MGD. Statistical analysis of the historical flow record also indicates that the 175 MGD current rated capacity will be exceeded 4 days per year under existing conditions. DEQ requires adequate treatment capacity by the year 2010 to prevent system overflows from winter storms, therefore in order to meet the State standard, the peak flow capacity of the treatment facilities will have to be increased from their current level. (3) My work on Region 2050 has made me even more interested in the importance of jurisdictions cooperating where possible. I thought Mayor Volta from Coburg made some excellent points about their needs. I'm concerned about the groundwater mgmt area due to nitrate pollution, and don't care for the fact that if Coburg builds their own plant, that will mean an additional river outflow. I'll be interested in the answers to the questions that the Mayor emailed about the Coburg issue, and want to ask an additional timing question. I don't want to hold up Eugene's adoption of the plan until the Coburg issue is resolved, but I would like to know how the Eugene City Council could indicate our support for seriously studying the ability of Coburg to be linked to the plant. Please see response to questions about Coburg, below. (4) The executive summary of the plan says the capacity deficit in wet weather will be 102 mgd (we have a capacity of 175 now, and need 277 in year 2025). Do the projects in the plan build the capacity to cover that deficit? More than that deficit? Less? Why? The Facilities Plan outlines the need for additional peak flow capacity, and the 20-Year Project List includes the specific capital improvements intended to alleviate the peak flow limitations and to address the deficit--no more and no less. The need is established by State regulations (overflow frequency related to the one-in-five-year storm event), and the capital projects on the list will result in the peak flow capacity necessary to comply with this standard. (5) Let me play devil's advocate. If (for example) the Eugene City Council didn't give our ok to the project list/plan now, and instead did so five years from now, what would be the most likely negative consequences?