Item A: City of Coburg Request for Connection to Regional Wastewater Facilities

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Staff has insufficient information to estimate the level of effort and resources that would be expected to study these issues for the purposes of evaluating Coburg’s request. Therefore, no associated work activities or costs are identified in Attachment A. Collection System And Treatment Facility Capacity The MWMC facilities, and the local wastewater collection systems for Eugene and Springfield, were planned and constructed to serve the anticipated populations within the Eugene-Springfield UGB. Therefore, these facilities, and long-range facilities plans have not accounted for the conveyance and treatment of Coburg’s wastewater. [Note however, Coburg’s wastewater contributions would be minor in comparison to the overall system capacity, under the growth projections presented in Coburg’s Facilities Plan.] The following collection and treatment system capacity issues would need to be addressed. Collection System Capacity Under the regional treatment alternative, Coburg’s studies show plans to convey wastewater through a force main (i.e., a pressurized pipe fed by a pumping station) that would cross the McKenzie River in the vicinity of Coburg Road, via the old railroad bridge. It would then connect with the Eugene collection system in one of several possible locations. In 2004, a preliminary evaluation was made of the viability of connecting Coburg’s wastewater discharge to the Eugene collection system. Further study would be needed to determine the optimal location for the connection and the extent to which capacity enhancements would be needed in the Eugene local wastewater collection system to handle the increased flows generated from Coburg. Treatment Facility Capacity In 2004, MWMC completed a 20-year Facilities Plan, which prescribes capital improvements needed to upgrade performance and expand capacity in various parts of the treatment works, biosolids management facilities, and regional pump stations. After over twenty years of operation, the treatment facilities currently experience capacity and environmental performance constraints in certain parts of the facilities under certain seasonal conditions. These capacity constraints include: 1) insufficient capacity during peak wet weather flow events, which has resulted in unpermitted overflows and bypasses in December, 2003; and 2) inadequate solids removal capability during rainy “dry season” months, which has resulted in exceedance of discharge permit limits for solids in May, 2005. Additionally, ammonia limits and temperature management requirements, which were newly added to the discharge permit, have added capacity constraints. All of these issues require construction of improvements to maintain permit compliance for existing sewer users and to add capacity for future users. The capital projects specified in the MWMC Facilities Plan will address the capacity and performance constraints for existing and future users through 2025. If completed in accordance with the adopted schedule, existing capacity constraints would be resolved prior to the estimated time frame of a Coburg connection (i.e. 2008). However, several factors have resulted in significant delays in capital project implementation, putting the MWMC system in greater jeopardy of failure to meet permit limits and key regulatory deadlines. Further study is needed to evaluate the adequacy of MWMC’s construction progress and whether any projects in the 20- year facilities plan would need to be accelerated to accommodate a Coburg connection without significant risk of permit violations. Page 6