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ALTERNATIVE SOLUTION TO REDUCE REAL SANITARY FLOW, not mystery surface water flow

Posted by Frank Burdick on 11 Feb, 2014
Category: Category 2 - about potential recommendations

PLEASE REVIEW THE ATTACHED FILE:

To: SSWWE CAC Citizen Volunteers, City Staff and Project Team
From: Frank Burdick, Citizen Volunteer
Date: February 8, 2014
RE: ALTERNATIVE METHOD TO REDUCE SANITARY FLOW

Subjects:
 a. Low Flow toilet, clothes washers, and showers
b. Water use restrictions during extreme wet weather conditions
c. Voter approved City Ordinance
d. For selected and specific homes, install check valves on the sanitary sewer lines.

EXECUTIVE SUMMARY
1. We have been asked to consider alternatives to the FDD program.

2. We have been told many times, including at the public meeting on 6Feb2014, that the intent of the FDD program was to address the sanitary sewer water “at the source.” For that reason, the FDD program was developed to attack the source of the flow AT the footing drain water DURING PEAK FLOW events.

3. What if we addressed the FLOW during ALL periods of time, 24/7/365 day per year? Real flow, not the mysterious underground flow that, seemingly, cannot be seen, monitored, or measured .

4. The following report will propose that, in lieu of FDDs and sump pumps, the City sponsors and pays for the installation of water conserving fixtures including low flow toilets, washing machines, and shower heads. In addition, similar to many other areas in country, the City could adopt “Water Use Restrictions” to be in effect during wet weather conditions or during the early spring thaw periods. A requirement would be that the City place an Ordinance on the Ballot for all Citizens to vote to approve these recommendations.

5. For certain homes in low lying areas, the homeowner could be offered a back flow preventing check valve if requested by the owners.

6. Using a factor of 2700 homes ( ie: an approximate number of homes with a current FDD/Sump Pump) the following report will show the following:

a. Overall flow for a period of 24 hours can be reduced by 167,319 gallons per day or 116.2 average gallons per minute.

b. The annual water conserved would be 61,071,491 gallons. This is equal to the peak flow of 54 storm events lasting 5 hours each by using the data from the 2001 SSOE Report ( 1. 4 gpm for footing drains for a 5 hour storm.)

c. The overall cost per home is substantially less than the FDD / Sump Pump installation. Cost saving per house could range between $1446.00 to $7,376.00 v/s $4100 or $10,000, respectively.

d. This approach is not unique and it has been adopted in other areas of the country.

e. This flow reduction would represent REAL flow, and benefit the City by reducing the overall impact to the Waste Water Treatment facility, every day, 24/7, 365 days a year….not just during peak flow periods

PLEASE NOTE, THIS IS THE THIRD ALTERNATIVE SOLUTION THAT I HAVE PROPOSED.  HOPEFULLY THIS ONE WILL RECEIVE MORE REVIEW AND PROPER CONSIDERATION THAN THE PREVIOUS ALTERNATIVES THAT I HAVE SUBMITTED.

Comments

Jim Osborn on 12 Feb, 2014:

This solution may help to add more capacity room to make room for future development, but it unfortunately does not save enough when compared to keeping rain water out of the  sewage flow. Since during a dry period, the sewer pipe is less that 50% full, in some places closer to a third, the low hanging fruit, the rainwater entering the system should be picked first.

The rain water entering the system is many times what can be saved though conservation.  This does not mean that FDDs are the answer, although they could be, but so is any method that reduces rainwater entering the system. Storm drain improvements are another solution.

Judy Hanway on 12 Feb, 2014:

I'd like to thank Frank for taking the time to figure out and propose this alternative solution. He obviously put a lot of time and effort into it. I plan to look it over carefully so that we can begin to discuss it on Thursday. Thanks Frank!

Michelle Lovasz on 12 Feb, 2014:

Frank, I am grateful for your initiative on this. It increases the
efficiency of the whole process.

Frank Burdick on 15 Feb, 2014:

I find in interesting that:
a. no supposed brainstorming occured at the 13Feb meeting. (We received a great lesson from Sample Town, that in hindsight, might have been better if it had been presented at the October 2013 meeting or sooner.
b. The topic of the above question (REAL water flow savings)barely got a cursery reference from the presentors as if they intend to gloss over it or not even consider it.
c. No mention of Mr. Fleethams previous request to establsh sub committees on the alternatives on the table.

Why is that, I wonder?? (Note, I just changed this text from (sshhh!) ALL CAPS to .....


Michelle Lovasz on 15 Feb, 2014:

Frank, many, if not all, are interested in discussing alternatives.  All of us at that meeting recognized the onslaught of questions so that not everyone even got a turn.  There is only so much time at a meeting.  We are free to make our own discussion time if what is allocated at the meetings is not sufficient, or, to establish our own sub committees on the alternatives on the table.  Come to my invitation...

Frank Burdick on 18 Feb, 2014:

note the recent ann arbor study   maybe its time that ann arbor citizens be made aware of water conservation 

http://annarborchronicle.com/wp-content/uploads/2013/12/Ann-Arbor-NCS-Results-DRAFT.pdf

The survey included 30 activities and behaviors for which respondents indicated how often they participated in or 
performed each, if at all. While most Participation ratings were similar to the benchmark, ratings for Mobility 
were higher than the benchmark (i.e., public transportation instead of driving and walked or biked instead of 
driving). 

Ratings for Natural Environment and Community Engagement were mixed; compared to other 
communities across the nation, more residents in Ann Arbor had recycled at home, but fewer had made efforts to conserve water, 

talked to neighbors, attended or watched a local meeting or read or watched the local news. While 
ratings for Built Environment, Recreation and Wellness and Education and Enrichment were all similar to the 
benchmark, the majority of respondents rated the features within these facets favorably. 

please forgive this lengthy post that is more than a few lines hopefully you will read itl

Joe Conen on 18 Feb, 2014:

I think water/sewer conservation activities are worthwhile for a number of reasons. We own a high efficiency washing machine, and selectively deploy some of the other techniques. That said, I am concerned that the localized peak flow reductions would be too low in areas if they have significant margin issues.
A rough estimate using a 5 hour  flowrate of 1.4 gpm per footing drain on average across 2700 homes results in a 3780 gpm total flowrate. The scale of this number is enormous compared to a 120 gpm reduction in the same number of homes using water conservation. 
Obviously using a higher peak flow like 4 gpm increases this difference. So, while I like the idea of savings 24-7-365,  it seems unlikely that this type of approach could move the needle on sanitary backups. When you say this approach has been adopted by other communities, do you know whether it was adopted to address sanitary overflows? If so, maybe there is data on its effectiveness.
Joe

Frank Burdick on 18 Feb, 2014:

joe, regarding your statement, "it seems unlikely that this type of approach could move the needle on sanitary backups"

my plan included low flow fixtures and and and....... water use restrictions during peak flow periods for the purpose of relieving the surcharges to sanitary piping.  

Joe Conen on 19 Feb, 2014:

Looking at your worksheet, the base case assumed 300 gallons of sanitary flow per day per home, or .208 gpm. Times 2700 home is 563 gpm. So even if all home went to zero flow (they won't/can't) this is still a very small reduction compared to the estimated footing drain flowrate of 3780 gpm.

Frank Burdick on 19 Feb, 2014:

This all depends on the duration of the peak flow storm event.  If the peak flow lasts only one hour:

1.4 gpm x 60min = 84 gallons x 5 hours (thats a BIG storm!!)= 420 gallons

I also think that it is not such a bad thing for the WWTP to receive a constant flow of surface water to help in their processing formulas. In addition, I will bet that Murat will tell us that keeping a certain quantity of flow in the pipes is a good thing...