Workshop developed by RCAP/AWWA and funded by the USEPA Sponsored By American Water Works Association AWWA Rocky Mountain Section RCAC Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 1
Acknowledgements Funded under a U.S. EPA grant to the Rural Community Assistance Partnership (RCAP) and its Partners. Purpose: Provide background knowledge and skills to equip operators to achieve and maintain compliance with the Safe Drinking Water Act. Additional RCAP Resources RCAP is a national non-profit providing training and technical assistance to small communities on water and wastewater issues. RCAP has over 160 field staff including certified operators; engineers; and specialists in utility management, finance, and administration. RCAP is funded by federal agencies and state contracts, and provides free services across the United States and its territories. More information can be found at www.rcap.org. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 2
Additional AWWA Resources Community Engineering Corps An alliance between AWWA, American Society of Civil Engineers, and Engineers Without Borders-USA to provide technical expertise to underserved US communities with infrastructure needs. www.communityengineeringcorps.org Partnership Programs An alliance of six drinking water organizations to improve the quality of water delivered to customers by optimizing water system operations. www.awwa.org/partnership Additional AWWA Resources Small Systems Resource Community Free online portal to tools and discussions of issues and developments related to small water systems. www.awwa.org/smallsystems The Water Equation AWWA s Water Equation provides academic and operator scholarships, student programs, and supports the Community Engineering Corp. volunteer program. The Association and its Sections partner to invest in the future of water and the industry s workforce. For more information, go to www.awwa.org/we Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 3
Today s Workshop Interactive review of the skills needed to solve today s challenges to providing safe water Includes the most common problems and challenges Discover the most effective field-tested solutions Topics include: Regulatory compliance, Disinfection, Nitrification, DBP control, and Source Water Protection Networking Important component of training Learn from wealth of experience in the room Certificates of Completion If you need a CEU certificate, you will need to confirm the following on the roster today before you leave: Is your name clearly spelled correctly? Did you provide an email address UNIQUE TO YOU? (do not use info@ type of email address) You must have an account on awwa.org to receive a certificate from AWWA and the email address you provide on the roster must match the email address registered to that account. If you do not have an account on awwa.org or if the email address you provide on the roster does not match the email address on your account, we will not be able to issue you a certificate until you create an account or update the email address on your account to match the email you provide If you have any issues with registering on awwa.org please contact Customer Service at 800.926.7337 or at service@awwa.org If you have questions about receiving or accessing your certificate, contact educationservices@awwa.org AWWA will apply to the water operator state licensing agency for CEU preapproval when applicable. You may be awarded CEUs by your agency. It is your responsibility to confirm with the agency that training meets relevancy criteria established for your license type, as some agencies may not apply CEUs to your license if the training topic is not relevant to your position. AWWA awards: 0.1 CEU = 1 contact hour or 1 Professional Development Hour (PDH) Questions? Please contact educationservices@awwa.org. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 4
Logistics Bathroom Location? Cell phones silent Break times Feel free to ask questions at any time 1. Name 2. Organization 3. Title/Job 4. Something interesting about yourself, not work related (family, hobby) Introductions Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 5
Pre-Test Required to capture pre-workshop knowledge levels in order to measure change in learning. (Post-Test following workshop.) Distribution System Infrastructure Workshop developed by RCAP/AWWA and funded by the USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 6
Learning Objectives Be able to describe components of the DS, and how they can impact water quality Be able to describe potential areas of water quality concern in your system, and consider ways to improve these Components we will discuss Distribution piping systems Valves Cross connections Storage tanks Hydrants Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 7
Pipe systems Different aspects of pipe networks can have impacts on water quality Dead ends Cross connections Main breaks Pipe systems - dead ends Effect on water quality Extended water age Decay of chlorine residual Increased DBPs Increased microorganisms If there is a failure some customers will not have water service. -As such, try to prevent a failure - event as best you can! Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 8
Solutions to dead ends Pipe loops Flushing valves Flushing program Dead end solutions - pipe loops Pipe loops make the distribution systemmore robust Allow more than 1 way for water to get to different points of distribution system Effect on water quality Decrease water age Help maintain disinfectantresidual Potentially reduce DBP and microbiological concentrations Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 9
Dead end solutions flushing Flushing valves Flushing programs Experiences with Dead Ends? Has anyone addressed a dead end in your system? What did you do? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 10
Valves Most commonly operated and widely dispersed components of distribution systems Types of valves Flushing Pressure regulating Flow control Isolation Backflow prevention Air release Buried-under-the-pavement valves Valves - Uses Isolate parts of the distribution system in case of leaks, maintenance, or water quality emergencies Control flow and/or pressure Release air that can accumulate in high points of the distribution system Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 11
Valves - Effect on Water Quality Closed valves create dead ends in the distribution system Stagnation Increased water age Biofilm development Sediment built up If opened or closed rapidly, water hammer can develop Valves - Solutions What can be done to limit water quality impacts? -Survey valves to be sure they are open - Exercise valves -Open and close valves slowly Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 12
Cross Connections Any point in a water distribution system where chemical, biological, or other contaminants may come into contact with potable water These contaminants can be drawn or pushed back into the water distribution system during a backflow event What is the Cross Connection? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 13
Storage Tanks Purpose Improve system hydraulics Peak flow/fire flow Balance treatment needs Factors that Impact Water Quality in Storage Stratification vs mixing Inlet/outlet configuration External contamination Increased water age Loss of chlorine residual Formation of DBPs Microscopic critters in the water BIG critters in the water Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 14
What can be done to maintain or improve water quality in storage? Reduce water age Booster chlorination Inspection and maintenance Some common storage tank problems Finished water storage not properly covered Cracks in the walls or storage cover Accesses and vents not protected with proper screen or other approved devices Storage facility not structurally sound Lack of normal maintenance and inspection schedule for storage tanks Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 15
Loss of integrity of storage facilities Knot hole in a spring box Hole in storage tank wall Courtesy Robert Clement, USEPA At least 3 bloated mice At least 7 snakes Inside the spring box with a knot hole Courtesy Robert Clement, USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 16
Hydrants Fire protection Flushing To improve water quality Caution water hammer Hydrant Impacts on Water Quality Flushing, scouring and cleaning (planned/unplanned) Cross connection potential Poor sampling points Water can be trapped in the barrel of the hydrant when closed, resulting in unrepresentative samples Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 17
EPANet Demonstration Identify vulnerable aspects of the distribution system, dead ends, pipe loops, storage etc. http://www.epa.gov/water-research/epanet Distribution System Components Dead Ends WTP Storage Tanks Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 18
Activity: Where would you expect to find water with the greatest age? Where would you expect to find water with the greatest age? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 19
Questions? Distribution Water Quality Workshop developed by RCAP/AWWA and funded by the USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 20
Learning Objectives Be able to describe what different water quality parameters tell us about distribution system health Be able to describe and apply key practices for managing water age and quality during storage Why water quality parameters are important Protect public health Comply with regulations Impact distribution system operation Impact aesthetics (taste, odor, color) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 21
Water quality parameters we will discuss ph Chlorine residual Water age Temperature Heterotrophic plate count Taste and odor ph Measurement of H + concentration lower ph more acidic EPA secondary standard -6.5 to 8.5 ph 7.0 is neutral neither acidic nor basic Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 22
Impacts of ph ph Too High: May precipitate excessive calcium carbonate in distribution system Restrict water flow in pipe ph Too Low: May corrode water pipes Red water issue (iron particulates) Pipe failure and rupture Lead and copper issues Impacts of ph ph impacts the form of Chlorine Chlorine is most effective between ph 5.5 7.5 ph impacts TOC removal Lower ph = better removal ph affects DBP formation Higher ph = more TTHMs Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 23
Chlorine Residual Maintaining a chlorine residual in the distribution system is critical to ensure pathogen-free water The maximum Cl 2 level is limited to 4.0 ppm under the Maximum Disinfectant Residual Level (MDRL) Unpleasant chlorine taste Excessive disinfection byproduct formation Other disinfectants (such as chlorine dioxide) also have MRDLs Chlorine Decay Chlorine degrades in the distribution system Reaction with natural organic matters (NOM) and/or pipe materials Booster chlorination may be needed to maintain an acceptable chlorine residual Rapid decay can be an indicator of a distribution system problem Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 24
Decay of Chlorine Residual Rate of decay can be affected by Water age Temperature Biological growth/nitrification Amount and type of chlorine-demanding compounds (organic and inorganic) Water Age The residence time of water in the distribution before reaching the customers Factors affecting water age: Water production rate Water demand Pipeline and storage tank operations Measure using tracer studies (fluoride) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 25
Water Age High water age: Loss of chlorine residual Increased risk of bacterial regrowth Increased DBP formation Higher chance of contamination AWWA recommends water age of less than 7 days Managing Water Age and Quality Manage Hydraulics in Storage Facilities Inlet/outlet configuration, baffling Increase turnover rate Pumping schedules (deep cycling) Mixing Manage chemistry Increase chlorine residual Shock chlorination Aeration (radon, TTHM, hydrogen sulfide, etc) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 26
Baffling Systems Adding baffle walls in the storage facility Make the interior channel-like to enhance a plugflow condition Make water age more uniform and reduce short circuiting Turnover Rate Achieved by: Decreasing storage volume Partially draining and refilling Account for seasonal water usage variations Close down some facilities during cold seasons or operate with lower volumes Important to ensure a certain minimum storage at all time for emergency purposes (e.g. fire flow) Set a minimum water level to prevent re-suspending any sediments Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 27
Pumping (Deep Cycling) Large water level fluctuations facilitate mixing and help increase turnover rates Pumping water when the tank is unusually low can cause scour and sediment release May not provide mixing of upper layers in a stratified tank Tank Mixing Even a storage facility that has a high turnover, older water zones can still occur Thermo stratification Short circuiting Adequate tank mixing can break up stratification and promote consistent water quality Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 28
Questions Do you know the typical / average water age of your distribution system? Where is your water age the highest? Temperature Water temperature can vary daily, and seasonally High water temperature: Quicker loss of chlorine residual More bacterial regrowth Higher disinfection byproduct formation Nitrification Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 29
Heterotrophic Plate Count An estimation of the number of live bacteria Quantified as the number of colony forming units (cfu) per 100 ml of water Indicator of system health Excellent indicator for nitrification in chloraminated system To identify causes of low chlorine residual Taste and Odor Chlorine taste and smell Chlorinated organic from sourcewater Di-and trichloramine Excess residual concentration Earthy-musty odor Natural Algae products (MIB and Geosmin) Algae under chlorine exposure Swampy or rotten egg odor Hydrogen sulfide Others (e.g. gasoline, metallic) From contaminations of various sources Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 30
Customers are a great source of water quality information Taste and odor issues can be a symptom pointing to other problems in the system, for example: Excessive chlorine taste may indicate chlorine overfeed Back flow through cross connections may be first noticed by change in taste/odor Use Customer Information Track customer complaints Investigate the origin of the problem Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 31
Discussion: Aesthetic Issues You received several complaints from customers. How do you respond? 1. Swimming pool smelling water 2. Red water coming out of the tap Other Storage Related Issues Corrosion Sedimentation Leaching Hydrogen sulfide release Biological issues Regrowth Nitrification Birds, insects, rodents, reptiles, etc.. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 32
Bacteria Regrowth Storage and piping often create an environment prone to regrowth Decreased chlorine residual Increased temperatures Build-up of nutrients High surface to volume in pipes Low velocity Bacteria Regrowth A public health and compliance concern May contain total coliform which leads to TCR compliance issues downstream May contain amoeba Loss of chlorine residual Nitrification Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 33
Discussion Water Quality Changes What interesting water quality issues have you seen in storage facilities Main Breaks and Cross Connections Workshop developed by RCAP/AWWA and funded by the USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 34
Learning Objectives Be able to preserve water quality when responding to a water main break Describe the difference between proactive and reactive responses Learning Objectives Contd. Be able to describe what a cross connection is and recognize a cross connection Be able to describe the seriousness of crossconnections, and importance of crossconnection control Describe requirements for cross-connection control Be able to outline the emergency response in the event of a backflow Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 35
Main Break how does it happen? Aging infrastructure a significant water line bursts on average every two minutes somewhere in the country $334.8 billion will be needed for pipe, treatment, storage,source, and other infrastructure over the 20 year period 2007-26 Frost load Pressure surge Mechanical damage Sabotage Main Break how does it happen? The rupture was caused by an emergency pump shutoff that increased pressure from 180 psi to 300 psi. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 36
Main Break - Consequences Potentially a safety hazard Flooding of surrounding area Property damage Traffic interruptions Main Break - Consequences Water service interruption Loss of pressure Contaminant intrusion May require bottled water or boil water order Loss of finished water High velocity scouring of pipes may dislodge sediments and increase turbidity Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 37
Corrective Measures Reactive Flushing (after break) Disinfection Make sure ALL valves are opened after disinfection It usually takes 3 or more valves to shut off a break, but only 1 to put the line back into service. Long-term - Asset Management Buried pipes are the most costly assets of most water utilities The rate of pipe failure is greater than the pipe renewal rate in most utilities Main Break Prevention 1. Develop a program to anticipate main breaks 2. Prioritize mains that need replacement and get them included in the Capital Improvement Plan 3. Develop a protocol for response to main breaks to limit adverse water quality effects Being proactive can reduce costs and protect water quality Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 38
Recommended Response in Case of Main Break Notify State State will assist with proper public notification Repair pipe Disinfect Pipe Take Coliform sample If possible pipe should remain out of service until Coliform results confirm there is no contamination Return to service Notify State Disinfecting New Pipes and Returning New Pipes to Service New water mains and those taken out of service should be disinfected before returning to service For the detailed procedures and requirements, go to: AWWA Standard C651-05 Disinfecting Water Mains Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 39
Disinfecting Pipe 4-step program can ensure the lines have been properly disinfected prior to being placed into service 1. Flush the line 2. Chlorinate 3. Flush to remove chlorinated water 4. Refill the line 4-Step Process 1. Flush the line to remove any particulates More effective than burning with chlorine Velocity > 2.5 fps Flush at least 2x the volume of the pipe 2. Chlorinate Should target a dose of 50 mg/l A 5 mg/l residual should remain after 24 hrs A higher chlorine dose can be used in in exchange for a shorter contact time Do not use dry chlorine (HTH) as granules may not fully dissolve Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 40
4-Step Process 3. Flush to remove chlorinated water (minimum two full pipe volumes) Chlorinated water must be dechlorinated prior to discharge in some areas 4. Refill the line and perform coliform sampling If results are negative the line is ready to be returned to service If results are positive, repeat from step 2 If positive results continue, pigging or additional flushing may be necessary Disinfecting Pipe What should you do if a pipe cannot remain out of service? Maintain a minimal distribution system residual of 0.5 to 1.0 mg/l Increase frequency of coliform sampling Consider a limited area Boil Water Notice (door hangers) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 41
Cross Connections Any point in a water distribution system where chemical, biological, or other contaminants may come into contact with potable water Contaminants can be drawn or pushed back into the water distribution system during a backflow event A dynamic problem since plumbing systems are constantly being installed, altered, and extended Cross Connections over 100,000 new cross-connections are formed each day (AWWARF, 2000) the greatest contributing factor to waterborne disease outbreaks in the U.S. (AWWARF, 2000) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 42
Cross Connections Contaminants can enter the distribution system through two mechanisms Backsiphonage Negative or reduced pressure in the supply piping, sucking nonpotable fluids into the distribution system Low pressure can be caused by line break or fire flow and others Backpressure: When a potable system is connected to a non-potable system working under a higher pressure, forcing non-potable water into the potable system Cross Connections: Backsiphonage Maryland Paraquat, an herbicide, entered the distribution system Cross connection between an herbicide holding tank and the potable water supply line USEPA, Cross-Connection Control Manual Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 43
Cross Connections Pennsylvania Low pressure in the supply line due to a line break Chlordane and heptachlor entered the distribution system through a cross connection (a hose immersed in a chemical tank) and backsiphonage USEPA, Cross-Connection Control Manual Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 44
Cross Connection Control Devices Air Gap: Twice the pipe diameter USEPA, Cross-Connection Control Manual Cross Connection Control Devices Atmospheric Vacuum Breaker Not designed to protect against back pressure conditions USEPA, Cross-Connection Control Manual Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 45
Cross Connection Control Devices Pressure Vacuum Breaker Not designed to protect against back pressure conditions USEPA, Cross-Connection Control Manual Cross Connection Control Devices Double check valve USEPA, Cross-Connection Control Manual Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 46
Cross Connection Control Devices Reduced pressure zone backflow preventer USEPA, Cross-Connection Control Manual What is wrong with this picture? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 47
What is wrong with this picture? What to do in case of a backflow event? 1. Stop the pressure differential that caused backflow of contamination, if possible 2. Identify and remove the cross connections 3. Contact state/ primacy regulatory agency 4. If harmful contaminants are suspected, provide immediate notice to the affected customers 5. Develop and carryout a plan for systematic flushing of the system 6. Continue to sample within and outside the suspected contaminated area Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 48
Online Resources USEPA Cross-Connection Control Manual http://www.epa.gov/safewater/crossconnectioncontrol/pdfs /crossconnection.pdf USEPA Cross-Connection Control: A Best Practices Guide http://www.epa.gov/safewater/smallsystems/pdfs/gui de_smallsystems_crossconnectioncontrol.pdf ASSE Series 5000, USC's FCCC & HR's "Manual of Cross- Connection Control", or UFL's TREEO's "Backflow Prevention Theory and Practice" Disinfection Overview Workshop developed by RCAP/AWWA and funded by the USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 49
Learning Objectives Be able to discuss the purpose and types of disinfection Be able to discuss the basics of chlorination and chloramination Topics to be Covered Why is disinfection needed? Types of disinfectants Chlorination basics Chloramination basics Unintended consequences of chloramination (nitrification) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 50
Why do water systems disinfect? To kill pathogens in water (from source or distribution system contamination) Residuals prevent biofilm buildup in the distribution system Adds an additional barrier to protect the public from waterborne disease Viruses Bacteria (e.g. E. coli) Protozoa Why do we need multiple barriers? Any barrier can fail Not all microbes are easily filtered (viruses) Not all microbes are disinfected by chlorine (Crypto) The cumulative effect of multiple barriers greatly reduces the likelihood of pathogens reaching the consumer Viruses Bacteria (e.g. E. coli) Protozoa Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 51
What are the types of disinfection? Chlorine Chloramines Chlorine dioxide Ozone UV (Ultraviolet disinfection) Which disinfectant(s) provide protection in the distribution system? Which disinfectants provide protection in the distribution system? Chlorine Chloramines Disinfectants that do not provide distribution system residuals (and not covered in this training): Chlorine dioxide Ozone UV (Ultraviolet disinfection) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 52
Chlorination Chlorine is the most common disinfectant used in the U.S. Common forms are: Chlorine gas Cl 2(g) + H 2 O HCl + HOCl + Cl - HOCl H + + OCl - Bleach (NaOCl) Chlorine powder (High Test Hypochlorite (HTH), Ca(OCl) 2 ) Impacts of ph on Chlorine Disinfection ph impacts the form of Chlorine Chlorine is most effective between ph 5.5 7.5 water H 2 0 hypochlorous acid HOCl H O H H O Cl ph dependent Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 53
Typical surface water chlorination Chlorination Pre-chlorination Primary Chlorination Secondary Chlorination Booster Chlorination Pre-Sedimentation Flocculation & Sedimentation Filtration Clear well Chloramination (Combined Chlorine) React free chlorine with ammonia to form chloramines, a weaker disinfectant HOCl + NH 3 NH 2 Cl + H 2 O (monochloramine) GOOD NH 2 Cl + HOCl NHCl 2 + H 2 O (dichloramine) NHCl 2 + HOCl NCl 3 + H 2 O (trichloramine) BAD Typically, monochloramine is the dominant species and is best disinfectant O H Cl plus H H N H Hypochlorous Acid Ammonia monochloramine (free chlorine) H N H Cl Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 54
Chloramination ammonia Free chlorine CT Chloramination Primary Chlorination ammonia Free chlorine CT if no pre-chlorine Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 55
Chloramination ammonia Typical groundwater chlorination Chlorination Primary Chlorination Secondary Chlorination Booster Chlorination Groundwater Well Storage Tank Distribution System Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 56
Chlorination with no free chlorine Typical groundwater chlorination ammonia/phosphate addition Primary Chlorination Groundwater Well Storage Tank Distribution System Booster Disinfection Chlorine decays in the distribution system Dosing chlorine in the distribution system (booster chlorination) maybe be required to maintain an acceptable chlorine residual Booster chlorination may pick up any free ammonia to produce chloramine Booster chloramination may be undertaken Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 57
Free, Combined and Total Chlorine Which do you use? What are the different types of chlorine? Free chlorine residual comprised of hypochlorite and hypochlorous acid HOCL and OCL - Combined chlorine chlorine combined with other water quality constituents Chloramines Total chlorine sum of free and combined chlorine Free Chlorine + Combined Chlorine = Total Chlorine Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 58
Free and Combined Chlorine Free chlorine Stronger oxidant Less stable, faster decay Combined chlorine (mostly chloramines) Weaker oxidants More stable, slower decay Do you chloraminate? Chloramines Produce very little TTHM and HAA5 Many utilities have switched to chloramination to comply with the Stage 2 DBPR Ammonia may cause biological growth or nitrification in the distribution system Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 59
Interaction between Chlorine and other Water Components Chlorination Dose How to ensure the right dosage is applied? Measure Cl 2 residual in the distribution system Make sure metering pump is working properly Check Cl 2 stock strength regularly Hypochlorite injector clogged with calcium Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 60
Chlorination Dose Chlorine decays over time in the distribution system Inadequate chlorine residual may enable pathogens to survive or multiply It is important to maintain an acceptable residual at all locations at all times Chlorine Dose Calculation What is the initial Cl 2 dose if: Stock chlorine solution is 10% Flow rate is 200 gpm Chlorine feed rate is 1.2 gph Chlorine concentration 1% NaOCl = 10,000 ppm = 10,000 mg/l 10% NaOCl = 100,000 ppm = 100,000 mg/l 1 gallon = 3.78 liters Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 61
Chlorine Dose Calculation Solution What is the initial Cl 2 dose if: Stock chlorine solution is 10% Flow rate is 200 gpm Chlorine feed rate is 1.2 gph Chlorine concentration 1% NaOCl = 10,000 ppm = 10,000 mg/l 10% NaOCl = 100,000 ppm = 100,000 mg/l 1 gallon = 3.78 liters Chlorine feed rate: 1.2 gph X 100,000 mg/l = (1.2 X 3.78)/60 X 100,000 mg/min = 7560 mg/min Chlorine concentration: chlorine feed rate / flow = 7560 / (200 X 3.78) mg/l = 10 mg/l Disinfection Monitoring Point of Entry Point of Entry Groundwater Well Storage Tank Distribution System Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 62
Monitoring Chlorine Concentration Point of Entry Residual disinfectant concentration cannot be less that 0.2 mg/l entering the distribution system for more than 4 hours Larger systems must be monitored continuously Lowest value must be recorded each day If the continuous monitoring equipment fails: Grab sampling every 4 hours, but for no more than 5 working days Monitoring Chlorine Concentration Point of Entry SHOW OF HANDS: How many have continuous analyzers? How often are they calibrated? weekly monthly don t know Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 63
Monitoring Chlorine Concentration in the Distribution System Cannot be undetectable in more than 5% of the samples collected from the distribution system Should be taken from the same location and at the same time as Total Coliform sample Nitrification Nitrifying bacteria feed on ammonia producing Nitrites which exert a chlorine demand which decreases the residual which allows microbes to flourish to produce more nitrites which continues the spiral until your residual is gone! aka feeding the beast Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 64
Nitrification Nitrification rates affected by: ph Temperature Dissolved oxygen concentration Free ammonia Water age Controlling Nitrification Keep the residual high during summer (4 mg/l not uncommon) Tank cycling (routine and deep but can lead to feeding the beast) Targeted DS Flushing At dead ends Throughout DS (unidirectional) At points of low chlorine Associated with tank cycling Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 65
Remediating Nitrification Complete DS Flushing Tank Draining (dropping the tank) Booster chlorination Free chlorination (DS burn) Source water break point chlorination (if you are not already) Chlorite addition (chlorite is regulated) Can nitrification be experienced in free chlorine systems? Some free ammonia may exist in natural waters What is your reaction when you get a complaint on a strong chlorine taste and odor? Trichloramines have the strongest chlorine odor and you actually need to increase the chlorine dose to achieve breakpoint/eliminate chlorine odor Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 66
Chloramination Recommendations Systems that chloraminate should have a Nitrification Control Plan that includes: The chlorine to ammonia ratio target Historical data graphed for analysis Operational targets: Procedures for chemical adjustment, monitoring and review of data The monitoring equipment/test kits and/or lab procedures that are approved/acceptable by USEPA/local regulatory agency Questions Does your system apply free chlorine only? Where is it applied? What is applied dose? What is measured residual at POE? What is measured residual in the distribution system? Does your system booster chlorinate? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 67
Coliform Sample Collection Workshop developed by RCAP/AWWA and funded by the USEPA Learning Objectives Be able to take and explain how to take a good coliform sample Recognize the challenges in taking a good sample Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 68
Coliform Sampling Why? Indicator of pathogen contamination Total Coliform (TC) Not necessarily a health threat in itself; used to indicate other potentially harmful bacteria A very common microbe Should be absent if chlorine residual is adequate. E. coli A subset of total coliform which indicates fecal waste contamination from mammals (humans, cows, etc) Found only in mammal feces Coliform Sampling Best Practices Collecting total coliform samples correctly and properly is absolutely critical in protecting public health Improper sampling is the most common reason for positive results (false positive) Repeated sampling requires extra effort, time, and money May lead to unnecessary MCL violation and subsequent corrective measures Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 69
Sampling Procedures 1. Assemble sampling supplies 2. Go to sampling location(s) specified in the sampling plan 3. Remove any aerators, strainers, or hoses from the tap 4. Open the cold water tap for about 2 to 3 minutes before collecting the sample 5. Fill out label, tag, and lab form in waterproof ink 6. Adjust the flow to about the width of a pencil Sampling Procedures, cont. 7. Remove the bottle cap 8. Fill the bottle to the shoulder or about ¼ inch from the top 9. Place the cap on the bottle and screw it down tightly 10. Turn the tap off and replace the aerator, strainer, or hose 11. Check the information on the label 12. Complete any additional lab forms that come with the sample bottle 13. Refrigerate or ice the samples; samples much reach the lab for processing within 30 hours of sample collection Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 70
1. Assemble Supplies 125 ml sterilized plastic bottle Dechlorination agent (do not rinse out bottle) Label and lab form (chain of custody form) Wash Your Hands! THINK STERILE! Assume your hands are dirty even after you wash them Preparation and Handling Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 71
Preparation and Handling Wear clean clothing, wash your hands and try to keep them bacteria free for the collection process Watch for contamination sources nearby activities soil disturbances- sewer lift stations animals/manure Avoid talking and disturbing the air while collecting (sneezing/coughing) Smoking during sample collection is not advised. If it is TC+ it will be you who has to recollect 2. Go to Location(s) in Sampling Plan - Sample Tap - Do s Tap should be clean, in good repair, and free of attachments Sample cold water only Valves that control hot and cold independently Water heaters can be laden with bacteria Use a line directly connected to the main Sample indoors, when possible Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 72
Question What could cause contamination? Sampling Taps DON Ts Sample tap should NOT be: Outdoors Too close to the bottom of the sink Swivel-type with a single valve for both hot and cold water Leaking or on a leaky pipe Threaded in the interior Upward flowing Located in a room of questionable sanitary conditions Attached to any household point-of-entry or point-of-use devices (e.g. aerators) Drinking fountains Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 73
What to Avoid Faucets to avoid: Swivel-type faucets that have a single valve for hot and cold water What to Avoid Outdoor faucets Faucets close to or below ground level Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 74
What to Avoid Faucets that point upward What to Avoid Faucets in places highly prone to contaminations (e.g. janitor s closet, public rest rooms) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 75
3. Remove Aerator, Strainer, or Hose Can trap sediment or particulates Biofilms can form in a hose 4. Open Cold Water for 2-3 Minutes Want to get water representative of conditions in the water main When temperature stabilizes is a good guide Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 76
5. Fill out Label, Tag, and Lab Form In waterproof ink Write clearly 6. Adjust Flow to Width of a Pencil You want a steady, controlled flow Don t change the flow once you start sampling (could dislodge microbial growth) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 77
7. Remove the Bottle Cap Be careful not to touch the inside of the bottle or bottle cap. Do not lay the cap down or put it in your pocket. STERILE, STERILE, STERILE!!!! 8. Fill Bottle to the Shoulder, ¼ Inch From the Top Don t rinse the bottle Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 78
9. Place Cap on Bottle and Screw it Down Tightly Think STERILE 10. Turn the Tap Off and Replace the Aerator, Strainer, or Hose Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 79
11. Check the Information on the Label 12. Complete any Additional Lab Forms Chain of custody Make sure to write clearly in ink Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 80
Chain of Custody Sample Sign in Sheet Who Transported Sample Date and Time of Delivery/drop off Number of Samples dropped off 13. Ice and Send to Lab for Processing Within 30 Hours Refrigeration recommended; Cooler with blue ice The quicker it gets to the lab the better Use a certified laboratory for analysis Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 81
Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 82
Helpful Hints Sample early in the week or month If you feel something went wrong, resample Bottles are cheap, but false positive samples are not Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 83
Common Issues that can lead to undesired results Improper Sampling Techniques Not Flushing the Tap Improper Handling of Bags Exceed 30 Hour Holding Time Avoid Sampling in the Rain Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 84
Keep your faucets maintained no spray Who s Responsible?? The WATER SYSTEM PERSONNEL are responsible for insuring that all water samples are collected during the correct compliance period Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 85
Failure to Monitor Utility responsible that the results go to the regulatory agency Violation occurs if no sample taken or reported Includes Public Notice and other measures Laboratory Results You will be notified by Region/District or Lab if you have a TC+ Sample Collect Repeats and Triggered Source samples within 24 hours or as scheduled May require corrective action be taken to resolve contamination Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 86
Colilert Test 1. Collect proper sample 2. Add one sample pack 3. Cap and shake 4. Incubate at 35 o C for 24 hours 5. Read results Negative - Less yellow than comparator Positive total coliform Yellow equal or greater Positive E. coli yellow and fluorescence Do-it Yourself??? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 87
Quantifying Results TC+ Discussion Who has experienced a TC+ event? What was the solution? Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 88
Online Resources A Small Systems Guide to the Total Coliform Rule http://www.epa.gov/ogwdw/disinfection/tcr/pdfs/s mall-tcr.pdf AWWA Video: Reliable Coliform Sampling for Water Systems http://www.awwa.org/store/productdetail.aspx?pro ductid=7089 Controlling Lead and Copper in Drinking Water Your name and contact info Your name and contact info Developed by RCAP/AWWA and funded by the USEPA Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 89
Acknowledgement: EPA National Priority Area 1: Training and Technical Assistance for Small Public Water Systems to Achieve and Maintain Compliance with the SDWA, EPA Grant X6-83560701 Rural Community Assistance Partnership Practical solutions for improving rural communities Western RCAP Rural Community Assistance Corporation (916) 447-2854 www.rcac.org Midwest RCAP Midwest Assistance Program (952) 758-4334 www.map-inc.org Southern RCAP Community Resource Group (479) 443-2700 www.crg.org Northeast RCAP RCAP Solutions (800) 488-1969 www.rcapsolutions.org Great Lakes RCAP WSOS Community Action Commission (800) 775-9767 www.glrcap.org RCAP National Office 1701 K St. NW, Suite 700 Washington, DC 20006 (800) 321-7227 www.rcap.org info@rcap.org Southeast RCAP Southeast Rural Community Assistance Project (866) 928-3731 www.southeastrcap.org Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 90
Purpose/Rationale This material will: Advise you of the requirements for addressing lead and copper in drinking water (specifically at small water systems) Inform you of potential future standards recommended by the National Drinking Water Advisory Council (NDWAC) regarding lead and copper in drinking water Explain how to be more effective in your efforts to protect public health Learning Objectives At the end of this course you should be able to: Apply the regulatory requirements of the Lead and Copper Rule to your system Calculate the 90 th concentration Summarize factors that will impact the release of lead and copper Take action to protect consumers from lead and copper Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 91
Agenda 0:00 0:05 Introduction 0:06 0:46 Regulations 0:47 1:12 Lead and copper basics 1:13 1:23 Conducting an inventory 1:24 1:44 Monitoring requirements 1:45 2:00 Treatment requirements 2:01 2:06 Public notification requirements 2:07 2:22 Lead service line replacement 2:23 2:27 Summary Pre-test: Controlling Lead and Copper in Drinking Water The pre-test will be handed out Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 92
Module One: Regulations Module One Learning Objectives At the end of this module you should be able to Summarize the purpose of the 1991 Lead and Copper Rule (LCR) Name the types of utilities that are subject to LCR requirements Demonstrate how to calculate the 90 th percentile for your system Describe additional requirements that may be triggered as a result of an Action Level (AL) exceedance Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 93
Why address lead? Young children and infants tend to absorb more lead than the average adult. Impaired mental development IQ deficits Shorter attention spans Low birth weight Adults -Increased blood pressure EPA set the MCLG at zero. Exposure to copper can cause stomach and intestinal distress, liver and kidney damage, and complications of Wilson s disease. EPA set an MCLG of 1.3 mg/l Copper Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 94
Rules that impact lead Reduction of lead in materials The Lead Ban (1986) The Reduction of Lead in Drinking Water Act (2011) Standards and Monitoring Requirements The Safe Drinking Water Act (1974) The Lead Contamination Control Act (LCCA) (1988) The Lead and Copper Rule (1991, revised 2000, 2007) Lead Regulations In materials 1986 Required use of lead free pipe, solder, and flux 0.2% lead in flux/solder - lead free 50% prior to 1986 <8% lead for pipes and pipe fixtures 1998 Banned fixtures that were not lead free 2011 Redefined lead free as 0.25% Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 95
Lead Regulations Standards and monitoring requirements 1974 MCL -0.050 mg/l SDWA 1988 -Lead Contamination Control Act Lead monitoring and reporting requirements for all schools (not enforceable) 1991 -Lead and Copper Rule (LCR) Action levels -0.015 mg/l lead, 1.3 mg/l Cu CWS and NTNCWS Minor revisions 2000, 2007 2017? Long-term revisions to the LCR LCR (1991) Maximum Contaminant Level Goals (MCLG) Lead 0 µg/l Copper 1.3 mg/l Action level based on the 90th percentile Lead - 15 µg/l Copper -1.3 mg/l Requires optimized corrosion control rather than a Maximum Contaminant Level (MCL) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 96
Actions for Lead Exceedance Water quality parameter monitoring Corrosion Control Treatment Source water monitoring Public education Lead service line replacement Lead and Copper Rule 1991 Overview CWS or NTNCWS Collects Lead and Copper Tap Samples 90th Percentile Is at or Below Both Action Levels* 90th Percentile Exceeds the Lead Action Level (15 μg/l) 90th Percentile Exceeds the Copper Action Level (1.3 mg/l) Conduct periodic lead and copper tap monitoring Begin LSLR replace 7% of LSLs per year Conduct public education due within 60 days Begin CCT steps includes WQP monitoring ** Conduct source water monitoring (Install SOWT, if needed) Conduct periodic lead and copper tap monitoring * Includes systems serving 50,000 people and (b)(3) systems ** Includes non-(b)(3) systems serving > 50,000 people, irrespective of their 90 th percentile levels; (b)(2) systems must collect WQPs. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 97
Activity-EPA Quick Reference Guide Monitoring What type systems is the rule applicable to? For public education Is public education required when copper action level is exceeded? Source water How frequently must a ground system monitor? Corrosion control treatment When must a small system conduct a CCT study. Potential future standards NDWAC recommendation -Development of a household action level Potentially lowering of the action level Requiring lead service line replacement Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 98
To calculate the 90 th percentile: Rank the samples according to their lead or copper concentrations Find the sample that: 90% of all samples have a lower concentration 10% of all samples have a higher concentration Sample # Lead (mg/l) 1 0.004 2 0.005 3 0.005 4 0.006 5 0.006 6 0.006 7 0.009 8 0.010 9 0.011 10 0.017 Activity: Determining the 90 th Percentile Your instructor will distribute handouts for this activity Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 99
Module Two: Lead and Copper Basics Module Two Learning Objectives At the end of this module, you should be able to: Name the two forms of lead that may be present in drinking water Discuss factors that can impact lead concentrations in drinking water Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 100
Rarely from source water or distribution mains Service lines Lead service lines, on either side of the meter Goosenecks or pigtails Customer plumbing Solder Plumbing fixtures Sources of Lead Ownership of System Components Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 101
Forms of lead There are two forms of lead: Dissolved lead Particulate lead Factors that impact dissolved lead concentrations Water quality parameters ph, alkalinity, dissolved inorganic carbon, hardness Chlorine residual levels, Presence of corrosion inhibitors Materials Other conditions Temperature, Flow velocity, Electrical current Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 102
Factors that impact particulate lead concentrations Operations practices that can impact lead levels Physical disturbances Repairing a main break Meter repair Hydraulic changes Flushing Valve/ hydrant testing Factors that can impact both dissolved and particulate concentrations Change in source water Changes in water chemistry Change in ph Change in chlorine residual levels Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 103
What would happen to lead levels if: 1. Seasonally switch between a surface water source and a ground water 2. Bring a new well into service 3. Repair a water main Discussion 4. Replace the service line between the main and meter Module Three: Conducting an Inventory Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 104
Module Three Learning Objectives At the end of this module, you should be able to: Name information sources you can use to inventory the materials used in your system Identify ways to tell whether or not a pipe is made of lead Conducting an inventory Installation records Codes, regulations Main renewal records Observations during construction Observation during meter replacement Customer reporting Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 105
Ways to tell if pipe is lead Scratch test Grey or color like a penny? Easy to scratch? Lead swabs Shape Magnet (will stick to steel, not lead) Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 106
Question Who has lead service lines? Have you conducted an inventory? What are the ages of homes in your system? Module Four: Monitoring Requirements Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 107
Module Four Learning Objectives At the end of this module, you should be able to: Discuss how to properly select sampling sites for a Community Water System as well as for a Non-Transient, Non-Community Water System Monitor your system as prescribed by Standard Monitoring and Reduced Monitoring requirements Follow procedures required to properly collect and manage lead and copper tap samples Monitoring Requirements Sampling sites with highest potential levels Frequency Set by regulation Reduced monitoring possible Procedures First-draw, try to observe the highest concentrations Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 108
Site selection CWS Three tier criteria to identify home with the highest risk Tier 1 Single family If lead service lines (50% of the sites) Copper pipe and lead solder after 1982 (and before lead ban 87/88) Tier 2 - Building/multi-family Tier 3 Lead solder before 1983 NTCNWS 2 tier criteria Tier 1 Lead service lines or Copper pipe and lead solder after 1982 (and before lead ban 87/88) Tier 2 Lead solder before 1983 Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 109
Minimum number of sites Systems without enough tiered sites must use representative sites Must identify sites in your monitoring plan Best to have more sites than the minimum required Minimum Number of Tap Samples System Population Number of Sampling Sites (on Routine Monitoring) Number of Sampling Sites (on Reduced Monitoring) >100,000 100 50 10,001 to 100,00 60 30 3,301 to 10,000 40 20 501 to 3,300 20 10 101 to 500 10 5 100 5 5 Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 110
Monitoring schedules Standard monitoring: Conducted at 6-month intervals from January-June or July-December Reduced monitoring Can be annual, triennial, or 9-year monitoring schedules. Conducted during a 4-month period from June- September Time of normal operation when highest likely lead levels Procedures for sampling First-draw 6-hour standing time One-liter volume System or residents can collect Samples are taken from kitchen/bathroom taps 222 Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 111
Issues and recent recommendations No water softeners or POU/POE Aerators Leave on Use wide mouth sample bottles (encourages higher flow rates) No pre-stagnant flushing States may invalidate a sample if Improper sample analysis Site selection criteria not met Sample container damaged Sample subjected to tampering It s difficult to invalidate a sample Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 112
Other samples Customer requested samples should not be included in the 90 th percentile calc. (states are still requiring these to be reported) Sampling not required at schools or public buildings (but recommended) Activity - Monitoring Your instructor will distribute handouts for this activity Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 113
Module Five: Treatment Requirements - Optimal Corrosion Control Treatment (OCCT) Module Five Learning Objectives At the end of this module, you should be able to: Explain why a small or medium system would decide to apply Optimal Corrosion Control Treatment (OCCT) techniques Summarize the purpose of Water Quality Parameter (WQP) Monitoring for small and medium systems Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 114
Optimal corrosion control treatment (OCCT) Chemical treatment designed to reduce the corrosivity of water Raising ph to make water less acidic Adding buffering to make water more stable Adding corrosion inhibitors to create a barrier to inhibit metals release OCCT required for large system Required for small/medium systems only if the action level is exceeded Water Quality Parameter Monitoring Required when < 50,000 that exceed AL > 50,000 regardless of 90th percentile* *(b)(3) systems not subject to CCT requirements (b)(3) system = 90th percentile lead -highest source water < 0.005 mg/l for 2 consec. 6 mos. Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 115
WQP Monitoring - Parameters Typical Water Quality Parameters ph 1 Orthophosphate 2 Alkalinity Silica 3 Calcium Temperature 1 Conductivity 1 Measured on-site. 2 Applies when a phosphate-containing inhibitor is used. 3 Applies when a silicate-containing inhibitor is used. Purpose of WQP monitoring To assist in determining water corrosivity To identify appropriate corrosion control treatment To determine whether corrosion control treatment is being properly maintained Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 116
Corrosion Control Treatment Steps Study/treatment recommendation by system State treatment determination Treatment installation Follow-up Pb/Cu tap & WQP monitoring State-specified operating parameters Determining The Best Corrosion Control Treatment Consult with your primacy agency Obtain recommendations of chemical suppliers Check with industries, hospitals, clinics, and wastewater plants Check with other water systems Don t experiment on the whole system Consider advantages and disadvantages of storing, handling and feeding various chemicals Developed by AWWA in partnership with RCAP and funded by USEPA, Published 2015 117