Skip to main content

Conceptual Value Engineering Study Yields Significant Cost Savings on Interceptor Relief Project

Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial

The East Branch of the Muddy Creek Interceptor (EBMCI) runs along the north bank of the Ohio River west of the downtown Cincinnati area. The approximately 32,000 foot long interceptor serves a combined sewer system, and 11 outfalls along the interceptor currently discharge approximately 460 million gallons of CSO in a typical year. In 2000, a study of the EBMCI by the Metropolitan Sewer District of Greater Cincinnati (MSDGC) concluded that the interceptor had insufficient capacity, and should be replaced. The proposed location of the new interceptor was intended to facilitate future sewer separation, and the work would have included replacement of four existing small pump stations along the route of the interceptor that were in poor condition. The plan recommended increasing the size of the existing interceptor from 15 to 24-inch diameter, with an estimated construction cost of 12.5 million.

As design proceeded on the interceptor relief project, the estimated construction cost climbed to approximately 97 million. The increase in estimated construction cost was driven by numerous utility conflicts, soil conditions, and changes to design criteria for peak flow capacity. These conditions required the invert elevation of the new interceptor to be lower than previously planned, resulting in the need to install much of the interceptor by microtunneling, and also increased the diameter of the interceptor.

As a result of the significant increase in project cost, MSDGC undertook a conceptual value engineering study to identify and evaluate potential alternatives to the current interceptor relief plan. The intent was to think “outside the box”, to identify alternative solutions to control CSO discharge volumes and improve the existing infrastructure. An initial range of alternatives was subjected to a series of screening steps involving sequentially more detailed evaluations. This approach encouraged innovative thinking, while preserving analysis budget for the more feasible alternatives. The initial brainstorming resulted in the identification of 39 alternatives, which were subsequently screened to 16 alternatives, and then to seven and finally to four, from which the preferred alternative was selected.

The alternative selected by MSDGC included the following elements:

Rehabilitate the existing interceptor by CIPP

Replace the four existing pump stations with four new pump stations with increased capacity

Implement sewer separation along the interceptor

Implement river inflow prevention measures

The selected alternative had an estimated construction cost of approximately 48 million, representing a savings of approximately 50 million over the previous plan. This plan would reduce the annual CSO discharge volume by approximately 96 percent in a typical rainfall year.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Data/Media
No Metrics

Keywords: CSO control; Conceptual value engineering; interceptor relief

Document Type: Research Article

Publication date: 2010-01-01

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Learn about the many other WEF member benefits and join today
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more