Columbus, Ohio's $2.5 Billion Plan to Reduce Overflows

"When the plan is implemented, there will be a dramatic decrease in sewer overflows and basement backups that occur in the city of Columbus service area after rains and snowmelt," the agency said Friday in a statement.

The plan addresses overflows from the separately sewered areas of the city as well as overflows from the combined sewer system. The total cost for the projects in the wet weather management plan is $2.5 billion.

Columbus submitted its wet weather management plan to Ohio EPA in 2005 in accordance with two separate consent orders issued by the Franklin County Court of Common Pleas in 2002 and 2004. The orders require Columbus to develop and implement a comprehensive plan to control overflows from the sewer system.

Flooded street in Columbus, Ohio. June 12, 2008 (Photo by Rick 59)

In its draft approval, the Ohio EPA gives the green light to the projects in the wet weather management plan and also to the schedule for implementing these projects.

The only exception is approval of the schedule for completing the final two phases of the Olentangy and Alum Creek relief tunnels.

The draft approval requires Columbus to submit an affordability analysis and rate study no later than July 1, 2016, with an accelerated schedule to complete the construction of those tunnels.

In the 2004 consent order, Columbus also was required to propose interim projects that could reduce the volume of overflow by 2010. In March, the Ohio EPA approved the interim plan that proposes several major projects to meet this requirement.

Construction of these projects is currently underway and is expected to reduce sewage discharges by approximately 540 million gallons in a typical year by 2010. The total cost for these interim projects is $729 million.

Once all projects are completed, it is estimated that remaining overflows from the system will be reduced to approximately 100 million gallons per year on average. This remaining overflow volume will not cause a violation of the water quality standards that protect human health and aquatic life.

This is primarily due to the relatively short duration of the discharge - approximately 15 hours total in an average year - and that the discharge will be to the Scioto River during high river flows, allowing significant dilution of the remaining overflow volume.

Columbus has projected a cost of over $350 million to eliminate the remaining overflow.

As a condition of approval of the wet weather management plan, Ohio EPA will require Columbus to periodically re-evaluate whether the remaining overflows can be further minimized or eliminated and Ohio EPA reserves the right to require additional controls.

Ohio EPA is also proposing to modify the wastewater discharge permits for Columbus' Jackson Pike and Southerly wastewater treatment plants. This proposal would require that Columbus implement the approved wet weather management plan. The plan would be consistent with the conditions outlined in the Ohio EPA draft approval.

The draft approval letter, proposed modifications to the city's wastewater discharge permits and fact sheet are online at: http://www.epa.state.oh.us/dsw/cso/columbus_ltcp.html.

Written comments and requests for a public hearing will be accepted through the close of business on August 25, 2008. Comments and requests should be addressed to Ohio EPA, Division of Surface Water, Permits Processing Unit, P.O. Box 1049, Columbus, Ohio 43216-1049, and Ohio EPA, Central District Office, P.O. Box 1049, Columbus, Ohio 43216-1049.

For information regarding sewer overflows, how they impact the environment, why they are a concern, where they are located in Ohio and what is being done to address their impact, log on to: http://www.epa.state.oh.us/dsw/cso/csoindex.html.

Copyright Environment News Service (ENS) 2008. All rights reserved.