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9. ENVIRONMENTAL REPORT requirements, changes in regulatory policy, and new treatment technologies drive the need for upgrades and expansion of the existing MWMC treatment facilities. 9.3 System Alternative 1--No Action 9.3.1 Affected Environment Although the entire Eugene-Springfield area could be indirectly impacted by the implementation of System Alternative 1, the area of greatest impact would likely occur in the vicinity of the present location of the WPCF, as well as areas in the Willamette River downstream from the WPCF outfall. In System Alternative 1, implementation of MWMC's preferred alternative (System Alternative 5) and the agency's next best alternative (System Alternative 4) would not occur. MWMC facilities would remain in their current operating configuration and the footprint of the facilities would remain unchanged. Upgrades and replacement of facilities and equipment that take place because of normal maintenance would continue to occur. Changes to equipment and operating procedures during normal maintenance would not constitute a major expansion or overhaul to the MWMC facilities. However, technological advances associated with these modifications could result in greater efficiencies and higher flow capacity. 9.3.2 Water Quality System Alternative I would result in significant potential impacts to water quality in the Willamette River and other local waterways. Impacts from the No Action Alternative would be greater than impacts from System Alternatives 5 and 4. If MWMC facilities are not upgraded or expanded, flows from all parts of the MWMC service area would continue to increase in conjunction with population growth and increasing industrial expansion in the Eugene-Springfield area. These flows would continue to go to the existing facilities, and the increasing volume would ultimately exceed the capacity of the treatment plant and conveyance system to treat the wastewater. There would be a strong likelihood that wastewater would overflow into the local environment whenever volumes exceeded the capacity of the treatment plant and conveyance system, thereby greatly increasing the risk of environmental health hazards and the potential for degrading the water quality in the Willamette River and other waterways. This situation would put MWMC out of compliance with its NPDES permit and violate the Clean Water Act and possibly other laws. Although No Action would provide no new capacity for existing facilities to treat flows from the service area, other MWMC programs and projects could be implemented under System Alternative 1. This could include continuation of programs to control the amount of I/I (groundwater and stormwater) that enters the conveyance pipelines through cracked pipes, leaky joints, manhole covers, and illegal connections such as storm and roof drains. MWMC and a CAC (Citizen's Advisory Committee) studied several methods of managing wet weather flows within the Wet Weather Flow Management Plan (WWFMP) (CH2M HILL, 2000). The recommended cost-effective solution by the CAC and governing bodies is to implement a "convey and treat" solution that includes pipe rehabilitation of the collection MWMC_9.0_REV14.DOC 9-5