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HomeMy WebLinkAbout10-24-2017 Worksession Packet 0 City of Oak Park Heights Worksession Date: Tuesday, October 24, 2017 Time: 5:30 p.m. Location: Oak Park Heights City Hall Conference Room 1. Call to Order 2. Water Chlorination 3. Election Polling Locations 4. Adjourn Page 1 of 8 THIS PAGE INTENTIONALLY LEFT BLANK Page 2 of 8 City of Oak Park Heights 14168 Oak Park Blvd N.•Box 2007.Oak Park Heights,MN 55082•Phone(651)439-4439•Fax 439-0574 Memorandum To: Eric Johnson, Administrator Cc: Mayor and Council From: Andrew Kegley, Public Works Director Date: 10118/17 Re: Water Chlorinating Pro's and Con's Draft Memo Oak Park Heights is one of a handful of small Cities in Minnesota that does not chlorinate potable drinking water on a regular basis. In the recent years, chlorination has been required of OPH by the Minnesota Department of Health due to water samples testing positive for Coliform bacteria. As we know coliform bacteria presence is not harmful in itself, however the department of health uses the presence of coliform bacteria as an indicator that other potentially harmful bacteria may exist in the drinking water. Subsequent testing for harmful bacteria such as P. coli thus far has always indicated no presence. Undoubtedly, recent construction on water main from 2013-2016 played a significant role in water samples testing positive for coliform bacteria. Coliform bacteria is naturally found in soil,plants, surface water and in the intestines of warm blooded animals, so anytime the interior of the water distribution system is exposed to elements, there is a great potential for coliform to enter the system. It is also possible remaining debris in the system that when stirred up could cause positive bacteria samples. In the spring of 2017, when investigating why a hydrant meter Ames/Lunda is using failed, a chunk of a 2x4 was found stuck in the impeller of the meter. The City's and MDH's investigation of the cause of Coliform presence in the drinking water lead to the same conclusion - recent construction of water main,more specifically exposing the City's water main with no free chlorine residual to disinfect was likely causing positive coliform presence in the drinking water. It was this determination that led the Department of Page 3 of 8 Health to require Oak Park Heights to chlorinate throughout the duration of the 2017 construction season. The construction season has ended for 2017,however I do believe discussion is necessary before deciding to simply terminate the chlorine feed. Below are some of my thoughts on the cons and pros of chlorinating OPH's water system. CONS OF CHLORINATING Chlorinated water is less desirable to Drink Long -time residents of OPH are not used to having the water chlorinated, which likely is the easiest argument to make against chlorinating the water system. When compared to non- chlorinated water, I'd wager most people will find chlorinated water less desirable to drink. Chlorinating will require more testing and reporting Systems that chlorinate drinking water on a routine basis must report chlorine concentrations to the MDH at each sampling site. The City of Oak Park heights currently monitors chlorine and fluoride at one sampling site per day for mandated Fluoride concentration reporting. The free chlorine level is tested and recorded for departmental monitoring only. If the City chlorinates on a regular basis, a chlorine sample will need to be submitted with each bacteria sample submitted to the Department of Health every two weeks. This increases chlorine sampling by six samples (or 12 testing ampules) every month. The resulting cost of the additional testing is about a$500 increase in supplies and materials for testing per year and an additional roughly twenty-five (25) labor hours per year. Small Potential for Disinfection Byproducts While protecting against microbial contamination is a top priority, water systems must also control disinfection byproducts (DBPs), which are chemical compounds formed unintentionally when chlorine reacts with natural organic matter in water. DBP's occur mostly in systems with surface water as the main source due to high levels of organic matter in surface water. OPH has very little to no organic matter in its well water. In the early 1970s, the EPA discovered that drinking water chlorination could form a group of byproducts known as trihalomethanes (THMs), including chloroform. The EPA set regulatory limits for THMs in 1979. While the available evidence does not prove that disinfection byproducts in drinking water cause adverse health effects in humans, high levels of these chemicals are certainly undesirable. 2 Page 4 of 8 Notwithstanding, the Department of Health will require OPH to test for disinfection byproducts, specifically trihalomethane (THM's) each year for a period determined by the MDH, then every 3-5 years thereafter. OPH staff's role in the testing is collecting samples and ensuring delivery to a MDH lab. Testing is done by MDH staff. Chlorine is Corrosive Chlorine is an acid and tends to increase corrosion of metals in water. Adding free chlorine appears to affect iron the most. Chlorine may also have an effect on copper and lead, but it may or may not increase corrosion with these metals. The Department of health requires Iead and copper concentration testing on a scheduled basis. The most recent lead and copper samples were taken in spring of 2017. Except for one home, all sample sites were below the action level for dissolved lead and copper in OPH supplied water. Fortunately OP14 source water has very low level of dissolved iron and other metals. It is however, very hard water in the farm of Calcium Carbonate (CAC03) at 240 mg/I or on a common water softener scale hardness of 14. One potential disadvantage of chlorine in water that has high levels of CAC03 is if the pH of water with high levels of CAC03 reaches 7.8-8.0 calcium flaking can occur. The pH of OPH's water system last tested in November of 2016 is 7.2. PROS OF CHLORINATING Water is disinfected: • Chlorine is an effective Germicide and has many advantages when used as a disinfectant in water systems: • Chlorine is inexpensive and assures safe bacteria and virus free drinking water. • In gas form it is easy to feed into the water system • Chlorine disinfectants reduce the level of many disease-causing microorganisms in drinking water to almost immeasurable levels. • Chlorine disinfectants eliminate slime bacteria, molds and algae that commonly grow in water towers, on the walls of water mains and mechanical fixtures such as pressure reducing valves and Altitude valves. • Should a positive coliform bacteria be discovered, we simply increase the chlorine level slightly rather than"shock"the system. Maintaining a minimum .2 ppm concentration of free chlorine at the Systems furthest point (Sunnyside) should safeguard against positive bacteria presence in the system. Page 5 of 8 Consistency in drinking water distribution My opinion is as it relates to providing drinking water is consistency is key. Further,providing safe drinking water is paramount. Water customers become aggravated and worried when there are sudden and constant changes in their drinking water. Alternating between feeding chlorine and not in short cycles because of the presence of bacteria,true or not communicates incompetence to water customers. The City does the best job possible with the resources available to communicate that drinking water remains safe even when Coliform Bacteria is discovered in the drinking water system, however there are inevitably some whose concerns are not eased by our assurance that the drinking water remains safe. With no intentions to make light of the seriousness of water sampling and testing, with no free chlorine residual in the system for disinfection, it is essentially a fingers crossed gamble that Coliform bacteria is not found in the system. Possible Changes to help improve the taste Staff could potentially lower the chlorine feed rate so the east portion of the City is .2 ppm. We currently chlorinate at the Department of Health recommended .5 - .9 ppm. The minimum acceptable level at the furthest point from the chlorine feed is .2 ppm of free chlorine. At the Current feed rate the tested concentration has been around .5 -.8 ppm. My recommendation- Continue Chlorination, for now. I recommend OPH continue chlorinating for the mean time. The City does not have to commit to chlorination for the long term at this point; although more failed water tests will trigger that requirement. I believe it is possible there could be remaining debris in the water mains and it needs to be worked out of the system. Dirt and sand that inadvertently found its way in to the pipes could possibly be contributing to positive bacteria results -specifically in the lower lying portions of OPH like Sunnyside where most positive bacteria samples are discovered. Further,there are at least two or three potential developments that propose to connect significant water main to the City's water system in 2018. If we choose to stop chlorinating now, and are forced to feed chlorine due to positive bacteria presence after water main connections are complete the City may no longer have a choice to chlorinate or not. 4 Page 6 of 8 POLLING LOCATION SURVEY Keep No Name Combine Separate Preference Comment Cannot justify keeping two places;there will be more people early voting. I used to be head election Janet Morgen x judge at the church location. Should not combine;people are used to going to David Beaudet x their polling places. I am a church voter,but it would not be Mary Anderson x inconvenient to come to City Hall. It would save money and reduce number of Karen McQuillan x volunteers needed. Great parking at City Hall,and it is easy to get in and Donna Dieientheis x out with cane. I don't care if there is one or two polling locations, but if there is only one 4 should be at City Hall Anonymous x because there is more parking there. Warren Wasescha x Makes total sense. Hope others agree. the parking at the church. Depending on how many Mary Jo Bouchie x people come out we can park right in front of the John Wolszon x Make sure there are enough voting stations. We are a small city-let's go to one place and use Ann Sheridan x our beautiful City Hall. Chris Doerr x Good idea! New to Oak Park Heights-so have nothing to base Don and Gayle Lobitz x an intelligent answer. If one polling place doesn't work after trying-have Anonymous x the option to go back to two polling places. I think more people will use absentee ballots in the future. I always vote at City Hall and have never had a long line to vote. Save the$3,000 and combine Anonymous x the locations. Anonymous x The church is on my way to work and convenient to vote first thing in the morning. It's also close to my Maruice McClurg x home. Combine if the$3,000 is saved rather than spent elsewhere. The 3%City spending increase is already excessive when the inflation rate is 1.6%. Need to Ken Smart x be smarter about spending decisions. The population of Oak Park Heights is going up-why Wally Abrahamson x cut a polling place? No preference,but keep the City Hall location for C.Hobrough x sure! It feels official to vote at City Hall. Saving money is good. We take advantage of voting Mike and Lori Magne x early. Meredith Moser x I agree with combining to one polfing location. Nadji Sutherland x Makes sense to combine and save money. Rollie and Judy Rubertus x Either are a good place to vote and combining down to one polling place for such a"smaller"area such as Oak Park Heights makes sense. Plus,I can easily Anonymous x walk to either site which is also an added plus. TOTAL 17 4 3 PERCENTAGE 70.83% 16.67% 12.50% Page 7 of 8 THIS PAGE INTENTIONALLY LEFT BLANK Page 8 of 8