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

2.32 -O- Why doesn't the upgrade of the AA WWTP increase capacity with the second treatment plant activation?

Posted by Lori Byron on 21 Dec, 2013
Category: Category 2 - about potential recommendations

Frank Burdick’s Log Number: 30
Submitted by: Burdick log
Category (1,2,3): 2
Status: Open
Estimated date to address: N/A

Q. Why doesn't the upgrade of the AA WWTP increase capacity with the second treatment plant activation? 

A. The current dry weather average daily flow into the treatment plant is 19.2 mgd. The projected need in 2025 is 24.3 mgd. The annual average daily design capacity of the City’s current wastewater treatment facility is 29.5 mgd. The wastewater treatment plant size is also constrained by its physical location. It is surrounded by railroad tracks, a creek, and the river.

Comments

Frank Burdick on 3 Feb, 2014:

tracking #10. Acknowledgement and Response

CRITICAL KEY ISSUE:  WWTP CAPACITY
THIS ISSUE IS DRIVING ALL ISSUES REGARDING FUTURE DEVELOPMENT IN ANN ARBOR, THE FDD PROGRAM, AND OTHER ONGOING STUDIES, and MOST CRITICAL, ANY FINAL RECOMMENDATION THAT WILL EVER COME OUT OF THIS CAC, if and when that time ever occurs.

IT IS CRITICAL THAT CITY COUNCIL AND THE CAC HAS A CLEAR UNDERSTANDING OF THE PAST, CURRENT, AND NEAR FUTURE CAPACITY OF THE WWTP.  THIS IS DRIVING OUR EFFORTS.  PLEASE TAKE THE TIME TO UNDERSTAND THE CAPACITY ISSUES AS NOTED BELOW.

During the 9JAN14 SSWWE meeting, CAC members inquired about the capacity of the WWTP, current on-going upgrades, and impact of development in the past 10 years as well as recently approved development projects.

The following are segments (in italics) of an email from Bill Higgins that will start the process of teaching us about the capacity of the WWTP.

CAC members need a primer to understand the complexity and issues with regard to Water, Surface Water, and Sanitary. 

During the 9Jan14 meetiing,  CAC members tried  to quiz  Craig Hupy on the Treatment Plant capacities.In Mr Hupy's response, he indicated that the Role of our SSWWE CAC is to study all conveyance issues including all systems "downstream to the Plant"

Mr Higgins, while sitting in the Public audiance I tried to inject a brief set of facts as he was able to
collect prior to the meeting.  He states, the CAC needs to know about in order to function. Because the rules of the CAC facilitator, Mr. Higgins was not given full attention and Mr. Hupy was not obligated to respond to this question from the Public, at that point in the meeting. 

Mr  Higgins, subsequently sent an email to Mr. Fleetham and L. Byrom requesting that the 9JAN meeting summary be added to the minutes of the meeting.
He states: 

The attached is what I came up with, suggesting that the numbers be verified and the capacity situation be added to the minutes.     I intend to also determine the ability of A2 to utilize the YSUA (Ypsi) capacity, only in the event of an emergency overflow....because the City or Consultant  does not appear to have this
"on the table".     
There needs to be a segment of time for visitor remarks immediately after a particular presentation, rather than at the end. 
 
The following is the start of the key issues regarding plant capacity:

Begin forwarded message:

From: William Higgins <whiggins27@gmail.com>
Date: January 25, 2014, 4:04:01 PM EST
To: charlie@projectinnovations.com, Hutchinson Nicholas <NHutchinson@a2gov.org>
Cc: chupy@a2gov.org
Subject: Minutes of Jan 9 SSWWE  Meeting

The minutes lack a corrective statement of Sanitary Treatment Plant capacity- a question asked
by CAC members.    The licensed treatment capacity  is 29,800,000 gallons per day  for TWO
plants and ONE integral detention. But one plant is, has been, and will continue to be out-of-
service for at least 4  1/2  years. Thus the useable capacity is more like 22,000,000 gallons per
day, with a nominal flow of 18,000,000 gallons per day.   Completion of the $152,000,000 up-
grade will only restore the licensed level of 29,800,00g/day.   An increase in the detention capacity is not planned.

(if any of the above can be shown to be incorrect, it would be the first public admission and would
be a welcome fact for the SSWWE and interested public.)
William Higgins

Jim Osborn on 3 Feb, 2014:

What is the main point of this? Mr. Higgins explained during the meeting that the plant has a capacity of just under 30 million gallons per day, and cannot be increased due to space limitations. The big tanks take a lot of space. Part of it, the older section, is being redone, temporally reducing the capacity to 22 million gallons per day. He mentioned all of this during our meeting.

I remember asking Mr. Higgins some pointed questions and he answered all of them.

Jim Osborn on 3 Feb, 2014:

" I intend to also determine the ability of A2 to utilize the YSUA (Ypsi) capacity, only in the event of an emergency overflow"

Why would YSUA agree to take any excess overflows from Ann Arbor? Agreeing to do so would be in effect reducing their capacity during heavy rains, when it is needed the most. 15 years ago, development in the Belleville area was limited due to a sewer plant being at capacity. This same problem happens elsewhere. Whey would they allow Ann Arbor to use up some of that valuable capacity?

Joe Conen on 3 Feb, 2014:

We will need to understand what kind of challenge storm water I&I presents to the treatment plant. This will be necessary to define the meaning of success for any recommendations we might make. This is the point of the capacity questions that need to be answered. Questions 2.16, 2.14  earlier are attempts to get this onto the discussion. (Those 2 questions should not be considered closed, based on the needed followup.)

Jim Osborn on 4 Feb, 2014:

I met William Higgins and found him to be sincere and looking for facts and a solution. Unfortunately, in the above E-mail from Mr. Higgins, that Frank posted for us, Mr. Higgins said, "(if any of the above can be shown to be incorrect, it would be the first public admission and..."

I don't care for the tone of this exchange, especially the phrase "...first public admission...", as it implies that the city staff and its consultants are covering something up, which I doubt. Why would they lie? This is not Watergate 1974 or "Monicagate" 1998, ("I did not have ...").

I believe that those working on this are honest and are not hiding the truth form us or trying to deceive us. If they were, why did they open up this study by conducting this whole CAC process? Tossing around such innuendo only detracts from our mission and cooperating with each other, and is counterproductive.

Lori Byron on 15 Mar, 2014:

[CITY] Here is additional information about plant capacity from the 2004 WWTP Facility Master Plan and current capacity:

The capacity of the retention and equalization facility is a function of the intensity and duration of a given storm event. With a total retention and equalization volume of 16.76 million gallons (including chlorine contact volume), it is possible to formulate how many days of storage is available based on a given peak day flow. Assuming the plant can handle incoming flows of 2.5-times the 2025 AADF of 24.3 MGD (or 60.75 mgd) and the 2025 peak hour flow of 72.7 MGD, a total of 11.95 MGD would need to be diverted to the flow Equalization and Retention Facility (72.7 mgd – 60.75 mgd). At this rate of diversion the peak hour design flow of 72.7 mgd could be sustained for approximately 1.4 days (16.7 mg/11.95 mgd) before the capacity of the equalization facility is exceeded.

Since that master plan was developed, the disinfection process was changed to ultra-violet (UV) light. The hydraulic capacity of the UV system is around 48 MGD or so. Doing the same analysis that B&V performed for the WWTP Facility Master Plan but using 48 MGD as the amount “the plant can handle”, the storage is around 16 hours.  Treatment plant staff consider this as a worst-case scenario, and would characterize our storage as being from 16 hours to 1.4 days.

Jim Osborn on 16 Mar, 2014:

How about spelling out what some of these things mean, such as MGD and mgd  and AADF.  I can guess, but that can be bad, Ann Arbor Daily Flow and Million Gallons Day, but then why the difference when in lower case? (of 24.3 MGD or 60.75 mgd)