Wednesday, August 13, 2014

DeKalb County Watershed Management provides City of Dunwoody 377 water test results over the last six months.

Based on this story, limited annual reporting and problems being reported in other cities; I decided to request information on the water quality testing being done by DeKalb within the City Dunwoody.   The City of Dunwoody trusts through an intergovernmental agreement that DeKalb Water will provide clean efficient water service to our citizens but as the person raising the possible issues with service (and being an elected official), I saw it as my responsibility to verify quality compliance.

Below is the reply from Mr. James Chansler, the Director of DeKalb Watershed Management where he provided me with three attachments including a spreadsheet of the tests conducted within the City.   I have reached out to Mr. Chansler, thanked him for the information and offered him an opportunity to present these results and other pertinent information to the community during a City Council Meeting.  In fact it is a standing offer, welcome anytime.

If anyone has questions regarding the tests conducted, methods of testing or the results; please feel free to reach out to me any way you like but I would prefer that the questions and comments be posted to the comments section in this blog in case another member of the community (or DeKalb) might have the answers.

Dunwoody Lab Results Jan thru July 7 2014.xlsx
Bacteria Definitions.docx
Water Production Laboratory Background.docx



Mr. Heneghan,

I’m sorry it took a while to put together the package of information to respond to your request, but I wanted it to be comprehensive--I think a cursory response would only leave more questions. I’ve attached an overview of USEPA/GEPD guidelines, the DeKalb County DWM laboratory and testing procedures, and spreadsheets for results from water sample testing done for Dunwoody this year. To be sure, drinking water system protection regulations are multi-layered and conservative at every level.

I am new to the Department of Watershed Management. I came to work for DeKalb County after the August 2013 event noted recently in the media and referred to in your email. First let me say that there was no “cover up” and never any "poor water quality" associated with the August 2013 boil water advisory.  I know stories in the media have only a limited time to get their point across, so I hope to share more information with you here...

Boil water advisories are issued in an abundance of caution and they happen at all water utilities (I have been through hundreds in my career.). The area determined to be included in an advisory is a judgment call based upon many things including--among many other potential factors--an evaluation of calls regarding reduced flow or pressure, exclusion of an area being cut off for non-payment, and a review of available plant telemetry information. And this judgment call is often made in "the heat of battle''' when employees are rushing and struggling to restore service.

In a follow-up review with our regulatory partner after the August 2013 event, we conceded that this advisory area might should have been larger. However, it is important to note that all water quality sampling after the event showed that there was no contamination of the system (I have never seen contamination after a pressure drop in a system). These test results confirm that no DeKalb water customers in or outside of the boil water advisory area were at risk as a result of the August 2013 event.

We are using the event as a  learning experience...and so are making some changes to help these folks that are in what is always a scramble to restore service. For example, we are installing more pressure reading devices in the system to help us better gauge the extent of issues of this nature in the future…and assigning the person responsible for determining boil water advisories to a group not involved in "the heat of battle" noted above.

The dedication and loyalty I've seen from the many professionals in our water industry is the reason that we have a safe and reliable water supply throughout our nation. I hope this background information helps to put the process into a larger perspective.

Thanks. -James

Overview of testing and results.
The Water Production Laboratory is a branch of the Operations Division and their primary function is to conduct all required sampling under the USEPA Safe Drinking Water Act for a large system. Georgia has Primacy from the USEPA and conducts all of the reviews, regulatory investigations and compliance activities through the Environmental Protection Division (EPD). As part of this process the laboratory is required by the Georgia Environmental Protection Division to monitor the water quality of the distribution system of DeKalb County.  The lab samples and tests the source water from the Chattahoochee entering the treatment plant and the final treated water as it enters the distribution system.  Internal process samples are conducted by the plant operations staff under their licensure as part of the plant process control. Our staff is well educated, experienced, trained and certified individuals who also maintain the lab certification to be able to conduct these tests.

Chemical and bacteria testing are performed daily on the source water.  The results of these analyses are used as part of the process control to establish chemical treatment rates.  During the treatment process, the water is monitored hourly, 24 hours a day, 7 days a week by the licensed plant operators.  Bacteria samples are collected every 8 hours for total coliform and heterotrophic plate count. 

Based on DeKalb’s population of around 700,000, the system is required to be sampled in at least 720 distribution different sites.  DeKalb currently has 769 sites so that if a site becomes un available anywhere in the County we will not go out of compliance.  These sites are required to be sampled every three months to assure a minimum of 240 samples per month.  The distribution system is divided into different areas for our sample routes.  For example, on Mondays samples are collected in the Dunwoody area, Tuesday is North and Central Decatur, Wednesday is Central and West DeKalb, Thursday is Lithonia and South DeKalb and then Friday is the Tucker area.  A total of 65 samples per week are collected routinely Monday through Friday.  

The primary focus on this sampling is to check for chlorine residual and total coliform.  Chlorine is the residual disinfection chemical we maintain in the system to protect the system from any additional contamination that might occur after the water leaves the plant and before I arrives at your tap for use. Total coliform testing is used to monitor the system for any potentially harmful bacterial contamination that could occur from compromises in the system such as leaks, cross connections or other issues. 

This is one level of protection in a variety of measures in place that include backflow control valves at business and industry sites, backflow devices in residential meter sets, operation of a Call Before You Dig location system to help prevent hits on our water lines, construction/building inspectors, plan reviewers, and several hundred employees working in the field who also protect the system. We do have staff for the field 24 hours per day. These components work together to provide a very thorough system to protect our water quality. As part of the sampling tests for pH, fluoride, iron and temperature are conducted.

If a sample tests positive for total coliform, the lab analyst returns to the site to do a resample at that site and also at sites upstream and downstream of the original sample point.  The majority of the time all of the resamples are negative for total coliform.  Occasionally, the original sample is positive again, but the other samples are negative.  In this case, the lab calls the business that had the positive sample to inform them they need to call a plumber to check the faucet.  The lab has never seen an instance where all the resamples came back all positive which would indicate a problem in the system. 

In addition to the required routine sampling, the lab also samples for main break events or any other situation when there is a possibility of water contamination. The number and area of samples is situational dependent on the size of main break, type of break and the area affected. The production laboratory also samples for new main sterilizations and renewals before these systems are allowed to be connected to the main distribution system. This type of sampling is done as needed when contractors call for an appointment. It takes two consecutive clear samples on separate days for the lines to pass.  

The lab is also responsible for handling customer calls and sampling if determined necessary to assist the customer with their water quality concerns. Many of these calls turn out to be aging piping systems in the houses that are leaching iron which causes a discoloration of the fixtures and water in the house, failing hot water tanks which contribute granular forms of water hardness in the plumbing or as simple as air in the water which causes a grey discoloration and clears upon standing.
Annually the lab also puts together the SDWA required Consumer Confidence Report which tells about the water quality for the pastyear to include any violations that have occurred related to the required elements.  This is sent out and placed on our website, at this time of year.

Attached to this is a spreadsheet showing the sample results for the Dunwoody area for the first six months of this year.

The map shows the distribution of the sample sites in Dunwoody Corporate limits of the 159 sites in this part of the County we use. We try to use business type sites so we have access to the site at times we need to sample. Residential sites pose access issues for taps that are used frequently enough to refresh the water from the main to the inside tap.

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