Introduction: In order to drastically reduce combined sewer overflows as fast as possible, Columbus Department of Public Utilities is planning to build a near surface relief sewer. Phase 1 would go from the Whittier Peninsula to Jackson Pike treatment plant, by crossing under the Scioto at Greenlawn Dam and cutting down the river side of Berliner Park. It would be constructed by 2010 and is predicted to reduce combined sewer overflows by almost 70%. The Sierra Club urges that restoration of damage from the 100 foot wide open cut trench be done with native plants.


INTERIM (2010) PLAN Application 01-303-PW

Central Ohio Sierra Club
36 West Gay Street, Ste 314; Columbus OH 43215

These comments are in response to the City of Columbus’ Combined Sewer Long Term Control – Interim (2010) Plan (“the Interim Control Plan”). The three components of the Interim Plan are the near surface relief sewer phase I, weir raising of combined sewer overflow (CSO) regulators, and treatment plant improvements. These comments are based on the Responsiveness Summary compiled and distributed by Ohio Environmental Protection Agency (OEPA).

Constraints on the Jackson Pike Treatment Facility

The Jackson Pike Treatment Facility is an important component of the Interim Control Plan, as well as the Wet Weather Management Plan. Even if proposed actions in the Interim Plan do not require more property, Jackson Pike is severely constrained and will become more so over time. The Sierra Club supports expansion of the Jackson Pike Wastewater Treatment Plant, not only treatment plant capacity, but also expanding the acreage available.

Impacts on Natural Areas and Parks (p. 2 of Responsiveness Summary)

Restoration and revegetation with native plants can lead to environmental improvement. Permits to install for surface disturbances should incorporate such an approach. Sewer easements will be necessary for the Interim Plan and can build toward a wider river corridor, with more generous buffers, revegetated with native plants.

Use Attainment and Antidegradation Status (p. 2-3 of Responsiveness Summary)

The proposed near surface tunnel for combined flows must achieve promised reductions and not just move the problem further downstream. OEPA has not completely addressed the questions raised by The Nature Conservancy about beneficial use redesignation, nor offered alternatives if promised benefits do not come to pass.

Summary of Discharges, Current, and Predicted (Pages 4-5 of Summary)

OEPA asked for discharges current, 2010, and 2030 from Columbus.

Table 1 summarizes most combined sewer overflows (CSOs). It predicts a 65% reduction in volume by 2010. Table 2 adds discharges from Whittier Street, with total CSO reductions promised. Calculations, however, are based only on averaged one year storm and larger storms would cause more overflows. Until the High Rate Treatment facility is complete, CSOs are predicted at Jackson Pike at least 12 times a year. After 2017, partially treated wastewater would be released from the HRT facility, and there would continue to be CSOs at least four times per year.

Table 3 shows sanitary sewer overflow points on main trunk sewers, so illustrates 12 out of the more than 100 total. Also, it only charts 2005 to 2010 and does not project beyond that. The 2030 scenario should be added.

The discussion of bypasses notes differences in modeling results. We support independent outside examination of the modeling. The Responsiveness Summary concludes that bypass frequency would be every 6 months for the one year storm – but more active at larger storm levels. There is no chart of bypass frequency, current or predicted. There is no discussion of how much additional flow would be diverted to Southerly and whether that would affect bypasses in wet weather. Combined wet weather flows at Southerly could be used to try and lower treatment standards.

Combined flows should be segregated, especially in wet weather. It is also important to continuously reduce total combined flow.

Environmental Damage and Public Access (page 5)

Coordination with Columbus Division of Recreation and Parks and planners is highly desirable. The goal must be to do better than “minimal environmental damage;” the goal should be to improve the river corridor aiming for a wider greenway with generous buffers. This goal can inform the Interim Control Plan and the longer term implementation of the Wet Weather Plan. An overarching goal to restore and enhance the river corridor will help with water quality, flooding, erosion control, stormwater management, and more.

General Comments on Interim Plan and Wet Weather Management Plan

The Sierra Club recognizes the urgency to reduce combined sewer overflows to meet the 2010 deadline of the 2004 Consent Order. It is important to keep combined flows separate during wet weather, thereby reducing total combined flows and untreated discharges.

The Interim Control Plan is the first step of the larger, longer Wet Weather Management Plan. We urge the City and Ohio EPA to keep working toward separation and reduction of combined flows, along with environmental restoration after surface disturbance. We urge aggressive implementation of the WWMP in 30 years, independent examination of modeling, and full biological treatment.