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City of Ann Arbor SSWWEP - Citizens Advisory Committee Coordination — City of Ann Arbor

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1.66 -C- In Morehead, there’s hard packed clay; how does that impact the differences in flows, pre and post FDD?

Posted by Lori Byron on 24 Jan, 2014
Category: Category 1 - SSWWEP Questions and Presentations

Frank Burdick’s Log Number: N/A
Submitted by: December CAC
Category (1,2,3): 1
Status: Closed
Estimated date to address: N/A

Q. In Morehead, there’s hard packed clay, which creates a bathtub effect around each house. It’s the same when you disturb the earth to install sewer pipes. How does that impact the differences in flows, pre and post FDD? [December CAC meeting]

A. Prior to FDD, this “bathtub” effect can drive a lot of flow to the sanitary sewer through the footing drain. This flow is removed from the sanitary sewer by FDD.

Comments

Frank Burdick on 24 Jan, 2014:

Who provided this response? Name and date

The same linear bath tub affect occurs at all sewer pipes.  Hence if there is a leak or crack in an existing buried pipe, the same phenomena occurs.  The linear bath tub of an undefined length  of pipe can drive the same surface flow down to the bottom of the trench and into sanitary sewer.  Hence, refer to question 13 from the Questions Log that asks, "Can the city provide a history of all efforts to "camera inspect" and repair existing sanitary sewers since 2001?"

Please provide a sample report for these inspections from the Morehead area.


Lori Byron on 13 Feb, 2014:

[CITY]

The City has electronic records of all sanitary sewers that have been televised since summer of 2006. Please see attached report (Q.2.38_Report of CCTV Work Since 2006.xls).   Prior to summer of 2006, records were not kept electronically. Records are archived and are less easily searchable.  The same applies for repair work performed on the system.  All the electronic records of repair work performed on the system is shown on the attached “Citywide Sanitary System Improvements.PDF” map.

Frank Burdick on 19 Feb, 2014:

Upon review of the attached Citywide Sanitary System Improvements.pdf map,  very little work is indicated as having been completed in targeted areas.

Why is that?

Lori Byron on 27 Feb, 2014:

[CITY]

A: The work that has been performed in the five study areas has been FDDs.  The condition of the sewers in these areas has not required other work.