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Prominent Project: Sanitary Sewer Wet Weather Evaluation
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Prominent Project: Sanitary Sewer Wet Weather Evaluation


Project Description

The Sanitary Sewer Wet Weather Evaluation project will:

  • measure how much the Footing Drain Disconnection program reduced stormwater flow to the sanitary system.
  • assess the risk of sewer backups in the City.
  • research and evaluate new ways to control the impacts of stormwater on the sanitary system.
  • ​recommend the method(s) to further reduce wet weather impacts to the sanitary system.​

Major tasks for the project include: system flow monitoring; updating the City's existing sanitary model; evaluating the effectiveness of the past FDD program; identifying alternatives for mitigating wet weather flow in the sanitary se​wer system; recommending a method(s) of miti​gation; as well as public engagement throughout the project. ​

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Upcoming Public Meetings​​​​​​​​​​

August 13, 2014 - SSWWEP CAC Meeting

6:30 p.m.

City Council Chambers

301 E. Huron St.​, ​Ann Arbor, MI

September 10, 2014 - SSWWEP CAC Meeting

6:30 p.m.

Location: TBD​

October 8, 2014 - SSWWEP CAC Meeting

6:30 p.m.

Location: TBD

November 12, 2014 - SSWWEP CAC Meeting

6:30 p.m.

Location: TBD

​Project Updates

April 17, 2014 - Video describing Ann Arbor's Wastewater Treatment Plant


March 21, 2014 - Video discribing​ the Developer Offset Mitigation Program and how it differs from the Footing Drain Disconnection Program. ​


​The consultant, OHM Advisors, completed the final analysis of the flow monitoring data collected from the five FDD target areas during the spring and summer of 2013.

On December 12, the Citizens Advisory Committee (CAC) met. At that meeting, the group:

  • Reviewed a presentation of the final results of the flow monitoring analysis, which evaluated whether the footing drain disconnection project had been effective in reducing the amount of stormwater that enters the sanitary sewer system. You can view the presentation here​ (PDF)

  • Key findings from the analysis included:

    • It is 99.8% probable that the 77% peak storm flow removal in the Orchard Hills District was caused by FDD.

    • It is 98.5% probable that the 72% peak storm flow removal in the Bromley District was caused by FDD.

    • It is 97.5% probable that the 61% peak storm flow removal in the Morehead District was caused by FDD.

    • It is 90% probable that the 38% peak storm flow removal in the Dartmoor District was caused by FDD.

    • It is 38.1% probable that the 12% peak storm flow removal in the Glen Leven District was caused by FDD.

    • In June 2000 there were 52 reported basement backups in the above five districts; in June 2013 there was 1.

  • Viewed and gave feedback on an educational video created as an overview of footing drains and the Sanitary Sewer Wet Weather Evaluation project.  That video is available at the top of this page.

  • Reviewed the Project Progress Report, available her​e (PDF)

  • Discussed the Technical Oversight & Advisory Group (TOAG), a group of subject matter experts, who will review the findings from this project, as well as the other three wet weather projects going on in and around the City:

  • Stormwater Model Calibration & Analysis

  • Upper Malletts Creek


The TOAG's charge is to review the data and results of all three projects, for technical expertise and cohesiveness between the projects.

The Citizens Advisory Group met on January 9, 2014. Following are the major topics/outcomes:

  • Discussion with Abigail Elias, Assistant City Attorney, addressing legal questions brought forth by a resident, challenging the FDD program.  Ms. Elias reported that the courts have upheld footing drain disconnection programs in other communities as an appropriate means to comply with the Federal Clean Water Act, which prohibits discharging raw sewage to rivers, lakes and streams. Ms. Elias also responded to a concern raised by a CAC member, that members could be held liable in lawsuits resulting from recommendations made to City Council. She stated that the risk of citizens being held liable for recommendations made in a voluntary capacity was very low and that if legal action were to be taken against CAC members, the City would defend them. She did note that the City would not defend a CAC member who was sued for incidents involving his or her personal conduct, such as assaulting another member. 

  • Following the presentation/discussion with Ms. Elias, the CAC agreed to the following:

    • The City's FDD program is presumed to be legal.

    • Further discussions about FDD legality are outside of the CAC scope.

    • The CAC will consider FDD continuation as an option going forward.

    • Any external harassment or badgering of CAC members about their work and/or opinions will be reported to the City Project Manager, Nick Hutchinson.

  • Reviewed the preliminary results of the FDD Survey conducted in December 2013. Over one-third of property owners who have had footing drains disconnected and sump pumps installed responded to the survey. Nearly 70% of respondents said that they are "satisfied or very satisfied" with the installation, while slightly more than 20% reported degrees of dissatisfaction.

  • In response to this statement:  "I would recommend a sump pump installation to a neighbor."  46% agreed they would recommend an installation to a neighbor and 24% disagreed with the statement.

  • 34% of respondents reported a significant reduction in anxiety or some reduction in anxiety, after the FDD and sump pump installation, but 40% reported some increase in anxiety or significant increase in anxiety, post FDD.

  • Craig Hupy, Public Area Services Administrator, congratulated the CAC on the positive role they had played in sponsoring and designing the survey, but he also indicated he was concerned that 40% of the respondents were anxious about their sump pump installations, and he was directing his staff to identify steps to reduce the anxiety.  Furthermore, he invited CAC members to help the City identify retroactive and go forward improvements in the FDD program.

  • Following the meeting, Judy Hanway, a meeting observer asked to join the CAC and also suggested inviting all survey respondents to a public meeting on the survey results.  The project team agreed with Ms. Hanway's request and pushed the public meeting from January 16th to February 6th to allow for time to mail invitations to the 800+ respondents.


If you have any questions, please contact Nick Hutchinson at

Past ​meeting material is available via the SSWWEP Library p​age​​.​​


Contact Information
Project Email:

Nick Hutchinson
Project Manager
Phone: 734-794-6430


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