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HomeMy WebLinkAbout7 - Prior Lake City Code Ordinance 91-01 < , AGENDA NUMBER: PREPARED BY: SUBJECT: DATE: INTRODUCTION: BACKGROUND: HERITAGE 1891 COMMUNITY 1991 rr7J:5V.\ ' 20J1 7 GARY STABER, BUILDING OFFICIAL CONSIDER ORDINANCE 91-01 AMENDING TITLE 9, CHAPTER 4 OF THE CITY CODE DECEMBER 16, 1991 Recent amendments to Minnesota rules promulgated b~ the Department of Health requires mun1cipalities to develop and maintain a comprehensive backflow prevention program. The Council was first introduced to this Ordinance on July 1, 1991, with an informal memo From City Manager Unmacht (see enclosed) . A backflow prevention program protects the public water supply system from contamination resulting from a back-siphonage situation. Attached are several examples of actual back-siphonage cases to illustrate the importance of this program. Compliance with these new rules four point implementation program. as follows: requires a They are 1. Develop an inventory of all reduced pressure zone and double check value-type backflow preventers. 2. Require that no such backflow preventers be installed without prior notice to the City. 3. Require the provision of tags on all such backflow preventers on which testers would record test dates. 4. such test and Require annual testing of all backflow preventers, as evidenced by records which are submitted to maintained by the municipality. This pr09ram will require Staff to conduct an on-site 1nspection of every commercial and industrial facility within the City limits of Prior Lake. It will also require an ongoing record keeping system to track compliance. 4629 Dakota St. S.E" Prior Lake, Minnesota 55372 I Ph, (612) 447-4230 / Fax (612) 447-4245 DISCUSSION: ALTERNATIVES: RECOMMENDATION: ACTION REQUIRED: The intent of this program is to protect the public water supply from accidental contamination. The backflow prevention program will not be used as a vehicle to require the updating of backflow prevention devices to toda~'s code requirements. There could be situat10ns in which backflow valves met code at the time of installing but because of code changes, no longer comply with today's codes. As long as the public water supply is protected from possible contamination, corrections will not be ordered. The final decision to order corrections will be with City Engineer Larry Anderson. Building inspection Staff will conduct site inspections of all commercial and industrial sites within Prior Lake. If any potentially dangerous conditions are found, correction will then be ordered. Costs associated with backflow prevention devices could exceed several thousand dollars in extreme situations. In order to maintain a good relationship with the business community, advanced inspection notices will be given along with written documentation explaining the backflow program. Any other public relations advice with respect to the implementation of this Ordinance is encouraged from the Council. 1. Direct Ordinance 91-01 to be placed on the next Council agenda for action. 2. Table the Backflow Program and request Staff research additional information. Because the Plumbing Code does not have retroactive authority, an ordinance is needed to allow staff to order the correction of a potentially dangerous existing condition. This could be done by adding the following amendment to Section 9-4-18 of the Prior Lake City Code. Motion to direct Ordinance 91-01 to be placed on the next Council Agenda for action. C I T Y 0 F P RIO R L A K E -~.._-- 4629 Dakota Street S.E., Prior Lake, KN 55372 Phone , (612) 447-4230 - FAX' 447-4245 .....__.v... ~:--..... _..... ---~.......-.. ~--- ~ INFORMAL MEMO 7-/- '1( TIME: ~#r ~d-.I FROM: /j-L SUBJECT: ~~~ DATE: ~ff. TO: MESSAGE: ih~i-4or ~~ $ hd/. ~ s;L,../ ~f&v~~ bl.i..':f ~r~$/~ ~. f Mdt -- pt( 'II gA' ttn /tLI1n ~d.' _ 0 ~ ,tt j,~frve /1 ~~ J ~ {J1I111I/Uf1" - ~ ~~ Response Required: Yes V No CITY OF PRIOR LAKE ORDINANCE NO. 91-0l AN ORDINANCE AMENDING TITLE 9, CHAPTER 4 OF PRIOR LAKE CITY CODE. The City Council does hereby ordain: l. A new Section 9-4-18 is hereby added to Title 9 of Prior Lake City Code which shall read as follows: 9-4-18: BACKFLOW PREVENTERS: No water pipe from the City water supply system shall be connected to any source of possible contamination without an approved backflow preventer. Required backflow preventers are listed in the Minnesota State Plumbing Code. If a possible source of contamination is found connected to the City water supply, the Inspector shall notify the owner, lessee or occupant to make the proper corrections, and if not done immediately, the public water supply shall be turned off. Before the water is turned on, the Inspector shall ascertain that the connection meets the Minnesota State Plumbing Code to prevent possible contamination of the public water supply. It shall be the responsibility of any owner, lessee or occupant to have all reduced pressure zone and double check valve-type backflow preventers tested annually. All testing must be done by individuals who are accredited by the Minnesota Department of Health. A tag shall be affixed to each backflow preventer showing the date and the name of the tester along with his/her accreditation number. In addition to the required tag, a copy of the test results shall be submitted to the Building Inspection Department of the City. 2 . 3 . The present Section 9-1-18 is hereby renumbered to 9-4-19. The present Section 9-1-19 is hereby renumbered to 9-4-20 and is hereby amended to read as follows: 9-4-20: PENALTY: Any person violating any provision of this Chapter shall, upon conviction thereof, be punished by a fine not exceeding seven hundred dollars ($700.00) or by imprisonment not exceeding ninety (90) days. A separate offense shall be deemed committed for each day the violation shall continue, and any person violating any of the provisions of this Chapter shall become liable to the City for any expense, loss or damage occasioned the City by reason of such violation. This ordinance shall become effective from and after its passage and publication. Passed by the CitJ Council of the City of Prior Lake this day of I 1991. ____ ATTEST: City Manager Mayor Published in the Prior Lake American on the ____ day of , 1991. Drafted By: Lommen, Nelson, Cole & Stageberg, P.A. 1800 IDS Center Minneapolis, Minnesota 55402 Chapter Two Public Health Significance of Cross-Connections :! Public health officials have long been aware of thl:! impact that cross-connections playas il thrrat 10 the public health Recausp plumhlng defects are so frequent and the opportunity for conta'minants to invade the public drinking water through cross-connect ions are so general. enteric infections caused by drinking water may occur at most an\' location and at uny lime. The following documented cilses of cross-connect Ion problems illustrate and emphasize how actual cross-connections have compromised the water quality and the public health, Human Blood in the Water System Health Department officials cut off the water supply to a funeral home located in a large southern city. after it was determined that human blood had contaminated the fresh water supply, City water and plumbing officials said thatthev did not think that the bloo-d contamination had spread beyond the building. however, inspectors were sent into the neighborhood to check for possible conlilminalion The chief plumhing inspt!clor hild received a tplephone cnll advising that blood was coming from drinking fountains within the building. Plumbing and county health department inspectors went to the scene and found evidence that the blood had bt~en cirruliltin~ In the wilter s\'stem wit h i n the building Thl~\' Immf'Cliately ordered the uullc..llng cut off from the water system at the meter, o Investigation revealed that the funeral home had been using a hydraulic aspirator to drain fluids from the bodies of human "remains" as pari of the embalming process. The aspirator directly connec:ted to the water supply system at a faucet outlet located on a sink in the "preparation" (embalming) room, Water flow through the aspirator created suction that was utilized to draw body flUids through a hose ilnd nerd:p attached 10 the suLlion sidl' of the aspirator, The contamination of the funeral home potable water supply was caused by a combination of low water pressure in conjunction with the simultaneous use of the aspirator, Instead of Ih(' bod\ fluids flowing into the , silnitilrv drain. the\ \\'I'rt' '4 drawn 'In the o!'!'c;silp. directIOn -into the fJolJblp water supply of the funerdl home! Nc'ma' ooe'ati()~ ;:~S :.,e 5.:: , Dres<"r~ ;:::ac e "a~,. ClCse~ .", NegatIve SuDOl> preSs",re Reverse flow Ihrough asoualor due 10 bac~ slpho~age 'Hydro Body fl~os . ~med In the .ower A resident of a small town in Alabama, jumped in the shower at 5 a,m. one morning in October, 1986, and when he got out his body was covered with tiny blilters. "The more I rubbed it, the worse it got." the 60 year old resident said, "It looked like someone took a blow torch and singed me." He and several other residents received medical trNtment at the emergency room of the local hospital after the water system was contaminated with sodium hydroxide, a strong caustic solution. Other residents claimed that. "It (the water) bubbled up and looked like Alka .mQI tlul~ storaoe d"Cl ~~HI'eJ ,..-.~ ---------- --~_. -- --- -------~ --- ------ Seltzer, I stuck my hand under the faucet and some blisters came up," One neighbor's head was covered with blisters after she washed her hair and others complained of burned throats or mouths after drinking the water, The incident began after an 8-inch water main, that fed the town. broke and was repaired, While repairing the water main, one workman suffered leg burns from a chemical in the water and required medical treatment, Measurements of the ph of the water were as high as 13 in some sections of the pipe, Investigation into the cause of the problem led to a possible source of the contamination from a nearby chemical company that distributes chemicals such as sodium hydroxide, The sodium hydroxide is brought to the plant in liquid form in bulk tanker trucks and is transferred to a holding tank and then pumped into 55 gal]on drums, When the water main broke, a truck driver was adding the water from the bottom of the tank truck instead of the top, and sodium hydroxide back-siphoned into the water main, Heating System Anti-Freeze into Potable Water Bangor Maine Water Department employees discovered poisonous anti-freeze in a homeowner's heating system and water supply in November. 1981, The incident occurred when they shut off the service line to the home to make repairs. With the flow of water to the house cut off. pressure In the lines in the house dropped and the anti-freeze. placed in the heating system to prevent freeze-up of an unused hot water heating system. drained out of the healing system Inlo house waler lines. and flowed out 10 the street. If it had not been noticed. it would have entered the homeowner's drinking water when Ihe water pressure was restored (Jon ;'.:c 0/1111" ,lOll il~') ""'~e I)' ".' 3 Employee Health Problems due to Cross-COnnection A cross-connection incident occurring in a modern seven.story office building located in a large city in New Hampshire. in March. 1980, resulted in numerous cases of nausea, diarrhea. loss of time and employee complaints IS to the poor quality of the water. On Saturday. March 1. 1980. a large fire occurred two blocks away from a seven.story oHice building in this large New Hampshire city. On Sunday, March 2, 1980. the maintenance crew of the orlice building arrived to perform the weekly cleaning. and after drinking the water from the drinking fountains. and sampling the coffee from the corree machines. noticed that the water smelled rubbery and had a strong bitter taste. ypon notifying the Manchester Water Company. water samples were taken and preliminary analYSIS disclosed that the contaminants found were not the typical contaminants associated with fire line disturbances. Investigating teams suspected that either the nearby fire could have siphoned contaminants from adjacent buildings into the water mains. or the contaminants could have been caused by a plumbing defiCiency occurring within the seven story building itself. Water ph levels of the building water indicated that an injection of chemicals had probably taken place within the seven-story building. Tracing of the water lines within the building pinpointed a 10.000 gallon hot-water storage tank that was used for heat storage in the solar heating system. It dId nOl have any backllow protection on the make.up supply line! As this storage tanlt pressure increased above the ~llDply pl'flssure. IS a result of thermal expansion. the potential for backprellun backflow was present. Normally. this would not occur because a boost pump in the supply line would keep the supply pressure' to the storage tank always' grealer than the highest,tanl pressure, The addition of I'\ISt inhibiting chemicals to this tank greatly increased the degree of hazard of the liquid, Unfortunately. at the same time that the fire toolt place. the pressure in the water mains was reduced to a dangerously low pressure and the low pressure cut-olf switches Simultaneously shot off the storage tank booster pumps. This combination allowed the boiler water, together with its chemical contaminants. the opportunity to enter the potable water supply withi. the building. When normal pressure was reestablished in the water mains, the booster pumps kicked in. and the contaminated water was delivered throughout the building, RO(,,' ,...~. .'ed SO'I' llt)"e'S o Ie mlen,"e W,ter """" ~~""''''''':./lo.''''''''' ,.~..~,. 9 . ..